Misfire caused by a misadjusted crank sensor (rubbing on flywheel)

Here, we’re diagnosing an intermittent misfire symptom, caused by an excessive crankshaft position sensor air gap. “Trash in, trash out” is how the saying goes, and this video is a perfect example. I’m also demonstrating the power of a lab scope, and the importance of verifying signal inputs before replacing parts.
Engine Performance Diagnostics chapter 21 page 20
Symptoms
- intermittent misfire
- no codes present
Fix
- adjust crankshaft position sensor air gap
Tests shown
- using an in-line spark tester to check for an ignition system issue
- checking an ignition coil primary current waveform with a lab scope and low amp probe
- checking camshaft and crankshaft position sensor waveforms for faults
- checking an ignition coil control signal (transistor external of the PCM)
- manually checking a crankshaft position sensor air gap
Tools used
- in-line spark tester
- Picoscope automotive 4 channel lab scope
- inductive low amp probe
Playlist
- (Chapter 21) Ignition inputs, cam and crank sensor
• (Chapter 21) Ignition ...
Related videos
- Hall effect cam/crank sensor operation and testing Part 1 (an SD Premium video)
• Hall effect cam/crank ...
- Hall effect cam/crank sensor operation and testing Part 2 (an SD Premium video)
• Hall effect cam/crank ...
- How to test a crank sensor (Chrysler Dodge Jeep)
• How to test a crank se...
- Faulty cam sensor setting a crank sensor code - P1389, P0320, P0622
• Faulty cam sensor sett...
For more information on this topic, I have written a “field manual” called Engine Performance Diagnostics which is available at www.scannerdanner.com as an eBook or paper book.
Want even more diagnostic training? Whether you are a DIY trying to fix your own car, someone looking to become an auto technician, or a current auto technician that wants to get more into diagnostics, subscribe to ScannerDanner Premium www.scannerdan... There is a 14 day free trial.
On ScannerDanner Premium I will bring you right into my classroom at Rosedale Technical College. You will find page for page lectures taken right from my book as well as exclusive classroom type case studies. What is so special about these classroom case studies? I pull live problem vehicles directly into my classroom and we troubleshoot them in real time, using and applying the theory and testing procedures we learn during the classroom lectures. There is no better on-line training of how to troubleshoot automotive electrical and electronics systems anywhere!
Disclaimer:
Due to factors beyond the control of ScannerDanner LLC, it cannot guarantee against unauthorized modifications of this information, or improper use of this information. ScannerDanner LLC assumes no liability for property damage or injury incurred as a result of any of the information contained in this video. ScannerDanner LLC recommends safe practices when working with power tools, automotive lifts, lifting tools, jack stands, electrical equipment, blunt instruments, chemicals, lubricants, or any other tools or equipment seen or implied in this video. Due to factors beyond the control of ScannerDanner LLC, no information contained in this video shall create any express or implied warranty or guarantee of any particular result. Any injury, damage or loss that may result from improper use of these tools, equipment, or the information contained in this video is the sole responsibility of the user and not ScannerDanner LLC.

[@campen777]

Hi , I've bin in the trade for over 40 years and wish I was starting again . Your enthrosiasm is second to none and your teaching is beyond words , I just hope your student realise how lucky they are . All the best from the uk .

[@SuperCarfix]

The best compliment that I can give you is that YOU made me a better technician.

[@ScannerDanner]

thank you and to encourage you, you are the type of guy we look for at Rosedale Tech. A true "field guy" (one that can actually fix cars) that is able to speak and convey his message or method of repair. all of the career "teachers" (guys that can't fix a sandwich) have never worked out. maybe they can teach in a classroom but put them in our live shop and they sink real fast.

[@cwj9202]

Paul, you are a credit to the automotive instructor profession. If I wasn't born in the forties, I'd attend your classes. At 27 minutes you emphasize the importance of the proper air gap, to which I would add that the magnetic force is effected by distance squared, so if you double the gap, the resultant force is FOUR times as weak. That coupled with an ECM which has a minimum threshold to be considered as a valid trigger pulse vs noise, the weaker pulses "seen" by the ECM may not be considered valid; thus, odd-ball oscilloscope shapes appear.

[@ScannerDanner]

Thanks so much Chad!

[@megasonify4800]

Chad, shop installed new distributor. Would they have needed to adjust cam sensors in the new distributor or does the factory set them to specs? Distributor solved my problem, but prior to installing new distributor I replaced the crank sensor and removed the spacer material (me the bozo!) on the end of the new sensor. It begins to miss when the car is at running temp. What is the best method to get correct spacing on crank sensor? Paul mentions quarter of an inch spacing in a reply below. That seems like a lot. I'm reading where it's only 1mm. Maybe he meant .025". At any rate, do you use a fiber washer or just push it all the way in then pull out slightly? Thanks.

[@cwj9202]

@@megasonify4800 - I would have to see the sensor and look up the specs for it. I am a heavy equipment mechanic, so I hardly work at all on spark ignition engines. All the sensors I have installed on the big stuff require pushing the sensor all the way in, but I always check the specs prior to installation just in case something has changed. I would recommend adhering to Paul's general recommendation.

[@megasonify4800]

Thanks Chad for the reply. Keep those D9s smiling. Looks like Paul responded in a msg to him directly. Great thread here, and I like you mentioned, awesome tutorial!

[@beansandgravy1]

i am in my sixties now and retired and i have never been kept so interested in a tech subject so much in my life.Your way of demonstrating and explaining your diagnosis and then proving the fault then the repair are second to none. Paul you are a credit to your trade i wish you well and you make an old man happy

[@PineHollowAutoDiagnostics]

Hi Paul, this video is definitely one of my favorites! Just used your methods to scope a hall-effect trans output sensor on a 01 Hyundai Sonata, code P0720. The signal was intermittent; turned out to be a bad contact at the sensor connector. Re-crimped the pins and saved the customer 100+ bucks, plus actually fixed the problem! You are an inspiration, keep up the awesome work. Your e-book and a 4-channel Picoscope are on my Christmas list.

[@megasonify4800]

PH, shop installed new distributor. Would they have needed to adjust cam sensors in the new distributor or does the factory set them to specs? Distributor solved my problem, but prior to installing new distributor I replaced the crank sensor and removed the spacer material (me the bozo!) on the end of the new sensor. It begins to miss when the car is at running temp. What is the best method to get correct spacing on crank sensor? Paul mentions quarter of an inch spacing in a reply below. That seems like a lot. I'm reading where it's only 1mm. Maybe he meant .025". At any rate, do you use a fiber washer or just push it all the way in then pull out slightly? Thanks.

[@JimmyDesantiago-xl9uv]

Dude. You’re gifted!! Went in circles trying to see what the hell was wrong with my 5.0

[@Viper81766]

Its not only techs who think you don't need a scope. Our local Community College Auto Tech teacher told me he NEVER needed a scope. He claims he worked in several new car Dealerships and never ever used or needed a scope. Sad isn't it. Paul brother you are the man. God bless

[@steelblackface]

Im a new mechanic and im learning a ton from your videos.

[@ScannerDanner]

You're in the right place! Welcome my new friend

[@steelblackface]

@@ScannerDanner thank you for sharing your knowledge.

[@felplayvina]

Love your videos, even more when you teach oscilloscope class, and of course see waveform is the way to fix this problems.

[@ScannerDanner]

Thank you so much. What an awesome compliment. Its comments like this that keep me pushing forward.

[@achill9603]

Solid diagnosis with no short cuts - great fault-finding demo for the pro and hobby mechanic alike.

[@sivucit]

Paul, I had a ego of thinking that i know everything, but in every video, you teach me one or other thing new and beat me to the ground. I think i just throw away my ego and just listen what you teach alll of us.. Great work. Truly appreciate your work. Simply amazing.

[@nunu4126]

I feel more confidence to work on car after watching your video's. thank you for your kindness to upload such a good informative video.

[@stuzman52]

Great video as always Paul. I just wanted to clarify about the switching of the hall effect sensor near the end of the video. You mentioned that when there was metal in front of the hall effect, the transistor was turned off. Actually, it would be turned on. This is evident by the long length of time at ground between the four pulses which would be seeing metal. Since it is a NPN transistor it would have to be turned on to pull the coil primary to ground. Keep up the good work.

[@ScannerDanner]

Thank you very much for the compliment! God bless you too my friend.

[@steveguest8028]

Great diagnosis Paul,I’ve personally had this problem with a transit van that wouldn’t start after one of our tech’s fitted a clutch which I found out was too large of an air gap on the crank sensor(VR type),I happened to fix this without the use of a scope but more by luck than judgement lol but here you show the advantage of a four channel scope perfectly....Many Thanks Great work 👍🏻

[@garytattan]

Paul Danner knows his stuff! Excellent video, please keep'em comin.

[@ScannerDanner]

will do gary tattan, thank you!

[@Amopower]

I've already had enough incentive to splurge for the 4-channel scope, so I got it two weeks ago. I think Paul should get some royalties for these sales!

[@ucnhtmenow1]

I learned to work on cars from my neighbor having me come over and help him swap tranny and motor's, being around him all the time when his car would break down and watch how he fixed it, and also buying a "race car" as my first car (had to work on it a lot). Lol I'm a mustang guy and even with everything I've learned through the years, I've never had a lot of the issues I see my buddies and other people have with their mustangs because basically everything was new on my builds (engine, ignition system, sensors, etc...), so I didn't have a lot of complex issues that older vehicles have but the basic stuff like fuel/h2o pumps, broken push rods, but that's about it. When I started working on newer vehicles and cars other than mustangs is when I started learning a lot more about ignition switches, catalytic converters (since none of my cars ever had converters), and the issues a lot of newer vehicles have. A class like this telling me what every part on a vehicle does (like the crank and/or camshaft sensor), while also watching it work, would broaden my horizons substancially. (Random rambling) ⤵️ When I talk to other car guys, they almost think I'm a newbie because I believe you can always learn something new, no matter how much you think you know from getting other people's view on things, and I sometimes ask the most simple of questions because I like to learn more. I was just never one of those guys that brags about what I know or how smart I may be or think I may be. For example, I worked at my buddy's machine shop running the CNC machine making gun parts and the programmer, who was autistic and had Asperger's syndrome, was no doubt the smartest guy in the building. That being said, the amount of stupid shyt he did, you would never know how smart he was if you didn't know him. Just because a brain surgeon can do brain surgery but doesn't even know how to change a flat tire, does that make them smart or intelligent? I don't think so, just educated in a certain area. People that have multiple talents and common sense would seem smart to me.

[@ScannerDanner]

...and they climb to the top with that mentality. Someone has to be the first one to find the "bugs". You know, before EVERYONE at the dealer knows what the problems are, and I can promise you that this guys uses a scope. Even at the dealer. It is a shame when a 20 year GM tech can't fix anything but a GM. This would be the true definition of a career parts changer.

[@christheother9088]

That is very clever incorporating the magnet in the sensor. SO much more elegant. The iron in the steel should reduce the reluctance in the magnetic field and intensify the field. (Like the iron laminations in a motor or electomagnet). I believe Hall Sensors can come in "normally on" or "normally off" flavors, so that would be selected accordingly. Nice vid, thanks.

[@malisa696]

Very nice video. I only do not understand why the ECU did not set any error code for crankshaft sensor because the sensor did send some very bad signals which where are out of range (my opinion), Anyway... good troubleshooting.

[@ScannerDanner]

yep, exactly. and the owner thinks he is getting ripped off on purpose but what it really is, is the mechanics incompetence. if you ask me this is the biggest reason why we get such a bad rap. it isn't that mechanics intentionally rip people off. it is simply bad calls, or an improper diagnosis. doctors do the same thing but people don't bitch because it is the insurance company that eats the cost of the "bad call"

[@billrimmer5596]

This is why I have SD premium on your website. This older free stuff is amazing, and I need to say thanx in a monetary way. That adjustable air gap was really cool. Just for the fun of it, I’m gonna hook up my old Vantage MT 2400 up and capture a histograph on a Hall effect crank sensor. Both adjustable air gaps. The spark tester and the crank sensor.

[@mihijojacobconaustismo5415]

Hey amigo how are you doing I was telling you about my 1993 Jeep Cherokee 4.0 last time And my air gap was bad I adjusted the way you said and now it’s working like a champ thank you man

[@ScannerDanner]

and you found this video! I think you commented on another one I did and I was thinking about sending you this video. Nice job my friend!

[@mihijojacobconaustismo5415]

yes thank you man by sharing all these videos you don't know how much money you save me God bless you exactly like you said when I touched it it was vibrating and knocking and I pull it out like a hair and tight the knot and boom no more misfire or cutting off God bless you man and thank you for replying

[@ScannerDanner]

Feels good to help others. Thanks man

[@Georg1979]

Great video Mr.Danner, as usual. And just like the other guy wrote it, I'm saving for a scope as well. And for sure I'll buy your book too. And I'm getting so excited about these videos, like I feel I'm alive again. And found what interest me the most. Maybe start a new career. I guess not many technicians can compete, with this kind of service technology and knowledge here in Hungary. God bless you and keep up the good work! You're one of the finest teachers I happened to know.

[@chrisi1909]

WOW, Cool Video again ! What a little Space can cause.... Thx for this one as always !

[@428dragpak]

Wow very impressed, instructors like you are what kids need, i was lucky to have one like you

[@spankeyfish]

This is a very interesting way to have a temperature related crank angle sensor problem. I guess the sensor must've been just close enough to work when the engine was cold but the combination of an aluminium crankcase and steel flywheel (alu expands twice as fast as steel) meant the sensor was being pulled just out of range as the crankcase warmed up.

[@ScannerDanner]

You would be correct my friend. It is a pull-down design circuit so the transistor has to be "on" during the low portion of the signal. I just kind of through that picture up at the end without thinking it thru. One thing we can agree on for sure is the magnetic field changes caused by the ferrous material or lack of is what is switching the transistor on and off. Certainly there are a lot of other components inside of the hall effect that I wasn't showing. (all of the base circuit controls)

[@ScannerDanner]

For sure my friend. And I understand that. Hopefully my videos do not come off as me trying to sell equipment because certainly that is not what I am trying to do. I'm just trying to show the techniques I use to troubleshoot auto electrical systems.

[@ScannerDanner]

thank you for your well thought out response!

[@asfan7]

Enjoy your videos, I've never seen anyone go through the steps you do to find out the issues but easy to follow. 99/100 mechanics probably would have just changed the cap/rotor & then the sensor never knowing what the real cause was.

[@ScannerDanner]

I am glad you find it easy to follow. That certainly is what I am going for. Thanks for the comment!

[@georgebonney90]

this vid and the jeep ckp sensor vid seems pretty straight forward but theres a lot of very valuable information in there,thx alot mr danner

[@lucianomanna9152]

This is truly a scientific approach to fixing car engines! Amazing video, amazing knowledge...

[@ScannerDanner]

that is a great compliment! thank you

[@crazycanadian05]

Great video Dan. I have seen lots of no start problems due to air gap issues after installing a new transmission. I have never seen it scoped out and causing a missfire though.. FYI if you do ever pull the sensor out, or replace one and it doesn't have anything for air gap.. You can take a cigarette pack cut a little tab of it, fold it in half and use some grease to stick it to the senor.. Then you just install the sensor and push it down as far as it will go.. This makes for a good air gap.

[@petersenlemos]

great job explaining it Paul!!!

[@ScannerDanner]

thank you and you will not be disappointed in the picoscope for sure!

[@blinkskaterkc]

ScannerDanner is a genius. Thanks for another great vid

[@bornagain125]

Paul, Thank you so much for sharing your vast troubleshooting knowledge. I bought your book and if you weren't on the other side of the country, I would love to become one of your students at Rosedale!

[@ScannerDanner]

O2 sensors with 5 or more wires are "wideband" O2s and supposedly cannot be monitored correctly with a scope. At least the signal circuit anyway. The heater circuit can be monitored just like every other O2 sensor. Some post cat. O2 sensors will shut the heater ckt off at times. Also some O2s use a pulse width modulated heater circuit. (pulsed on and off to control current flow)

[@georgebonney90]

There wouldn't be any other way to check functionality of a crank sensor or a cam sensor? Especially in relation to one another, great lesson

[@res3571]

Amazing explanation, keep the good work! thanks!

[@TRcustomengineering]

Wow, Awesome video. This is true diagnostics right here folks! Thanks again Paul.

[@ScannerDanner]

yes, but I think on this particular design you can't put it on wrong. I'll look at the mounting points for the crankshaft tomorrow. I think it either has an offset bolt or you can bolt it up in three different locations which wouldn't change timing on this design due to the three sets of windows that are all the same at 120 degrees apart.

[@newfiemech5]

Great video, thanks for your dedication to our profession. Don't forget about the Dodge flywheels with the busted center, they'll give you a wonky crank sensor signal as well, kinda like the one you had that was hitting the crank sensor. Good catch on this one though...keep it up!!

[@ScannerDanner]

no, I just pretend to:-) seriously though, I still have a lot to learn and am still learning new things everyday!

[@randallboyd5920]

I woulda still put a crank sensor in it. Just to cover all my basis. Just to make 100% no comeback. Great video.your Top of the field man.

[@ScannerDanner]

Thank you Randall!

[@Georg1979]

Plus it's better for the shop, because most of their income is from selling parts. And in this case they wouldn't have sold anything. And what it took? 1hour labor? That's just not profitable for a shop. So you're right. And if nothin' changes, we know it won't. Mr.Danner can compete with them and cash in some some good money because of it. And to be honest, he deserves every $ for what he's doing. Both in the school and out on the field.

[@SuperCarfix]

I think the number of channel a tech needs depends on how good he is.For me one channel is too many and for you Paul 10 channel is not enough..Thank you

[@therealspixycat]

Hi Dann. I worked on issue were the engine would cut out just out of the blue and no restart and no fault codes. Fault occurred during warm days. Suspected crank sensor: took it out and saw several scratches on the top of the sensor and a couple of metal filings (sensor has an internal magnet). I suspect that during a warm or hot day the flywheel sometimes scratches the top of the sensor causing the ECU to loose all timing causing the ECU to cut out the engine. For now I filed the top of the sensor to be clean. Not sure if this fixes it. I have no scope.

[@ScannerDanner]

what you could do is rig up an old spark plug wire. I used to do this on the GM quad 4 engines all the time. the in-line spark tester I used in this video wouldn't work. it is not insulated enough. it would short out on the sides of the cylinder head.

[@gmtech4327]

Once again another great training video Paul!!! Another good place to find the picoscope is from autonerdzdotcom and they provide invaluable support and training with your purchase. Various levels of the Picoscope are available from beginner (PicoQuad 4000 Lite) to the advanced (PicoQuad 4000 Deluxe).

[@attilakohbor3360]

Excellent presentation Paul , thanks.

[@SteveRobReviews]

Fantastic resolve, well presented. Thank You. Steve.

[@ScannerDanner]

literally, a quarter of an inch air gap adjustment fixed this problem. thanks for the comment

[@stuzman52]

Paul, with these type of designs of where a sensor is looking at the flywheel, I would assume that it's critical that the flywheel if removed, goes back on in the correct position. Otherwise, the timing of the crank sensor signal would be out of time with the cam sensor signal. Is my thinking correct in this regard? Thanks!

[@ScannerDanner]

@campen777 thank you so much! what a great compliment.

[@javierescontrias]

Excellent video. I have a 99 Durango that stopped running and after changing spark plugs, wires, coil, distributor and distributor timing sensor I finally got it running by changing the crank timing sensor. The odd thing is that the old sensor has rub marks on it so now I'm wondering if the flywheel is somehow spinning out of center because I hear this clicking that's rpm dependant. Again thanks for the video.

[@ScannerDanner]

any scope is better than no scope don't you think? Picoscope and Vantage Pro would be my top choices.

[@robertwelch3899]

I want Eric O's Autel. What is that? MS 906? Really wanna get one... I think the MS 906bt? is the one I really want. He says the scope isnt the greatest I believe he said mainly cause you cant turn peak detect off but everything else about it seems awesome. The Verus seems like a great tool but way out of the rang of anything I could ever afford. Love watching eric o etch ivan and sd. I feel like I'm learning so much. Now I just gotta get the equipment so I can actually put the information to good use.

[@robertwelch3899]

Etcg***

[@padraiggalvin2807]

Great video. You covered all aspects of the problem. I must say that inline spark tester is a great tool do for something so simple. The scope is wonderful of course but that spark tester instantly put you in the right direction. Even a small miss of spark on that and the naked eye would see it. I also find it interesting how the signal from ecu to the coil has a sloping edge at the start of it. I had the same on a nissan a while back. thought it should be like the cam sensor -on/off instantly

[@megasonify4800]

Padraig, shop installed new distributor. Would they have needed to adjust cam sensors in the new distributor or does the factory set them to specs? Distributor solved my problem, but prior to installing new distributor I replaced the crank sensor and removed the spacer material (me the bozo!) on the end of the new sensor. It begins to miss when the car is at running temp. What is the best method to get correct spacing on crank sensor? Paul mentions quarter of an inch spacing in a reply below. That seems like a lot. I'm reading where it's only 1mm. Maybe he meant .025". At any rate, do you use a fiber washer or just push it all the way in then pull out slightly? Thanks.

[@padraiggalvin2807]

@@megasonify4800 If distributor can be adjusted i would say it needs to be. You should have to open and adjust anything inside but im not familiar with this engine. If you use a hacksaw blade which is 1mm or less for airgap then that should be good

[@wilborth5th]

Personally I think that ignorance is the main reason our world is in constant war and conflicts knowledge is too scarce, now days information is closer to reach, is up to us to find it and to take advantage of it, how many people sell or donate or even give up of their possessions and then they go out there and get into even deeper debt? Being they the problem in their vehicles were something simple to resolve! Before the digital era people had to go to school regardless sometimes wait for next day or next Monday to go to the library to find the info they needed, today a click of a button and there it is, anyways thanks for such Golden video, greatly great full” if that’s a valid frase

[@ScannerDanner]

ahh, that was tricky. I loosened the bolt just enough to where I could move the sensor in and out with a small prybar. I then pushed it in all the way and ever so slightly backed it out. (again, with using a prybar). This prevented the sensor from slipping in its adjustment when I tightened the bolt the rest of the way. Wish I could have filmed that part. No room for my hands, the pry bar and the camera.

[@ScannerDanner]

Thanks man! I really appreciate it. Paul

[@nickayivor8432]

SUBSTANTIAL Sir ScannerDanner Thank you Sir ScannerDanner From Nick Ayivor from London England UK 🇬🇧

[@crazycanadian05]

Dan you are right. This flexplate can only be installed 1 direction, that way the windows are always in the right spot. You do have to watch out for different variations in the torque converter mounting pads (some have ans offset bolt, some of the newier ones don't), also the length of the torque converter mounting bolt. If its to long it will dimple the toque converter and wipe out the lock up clutch.

[@jjbailey01]

I finally got the problem to show itself while the scope was hooked up. The crank signal is normally 0-8v. When the problem happens, that signal goes to 6v baseline instead of 0v. I can't think of a wiring issue that would do this. So it is most likely the sensor. Hopefully not the ECM.

[@jamesmeglio6447]

Excellent explanations, and demos..... thanks

[@ScannerDanner]

I hear that a lot from dealer techs and they are actually right in some ways. When you see the same car over and over again with the same problem, you don't need a scope to find the fault. you've done 10 of them this week alone:-) Don't get me wrong, I know some awesome "dealer" techs. What they do different is they are not happy with just changing the part. They take the time and find out why.........

[@ScannerDanner]

yep autonerdz would be another place with the bonus of additional training included in your purchase. there are some really smart guys over there for sure!

[@Georg1979]

One of my colleagues almost died from a bad diagnosis. After the doctors have found out, what was the cause of his illness, it was almost too late. Now he lives, but lost his job.

[@trucker61621]

You the man,Dan !! Thanks

[@ScannerDanner]

there is a ramp. I am just "zoomed out" too far to see it clearly. In fact it is very clear on a smaller time base. The air gap issue is even more critical on a magnetic type sensor. If you have my eBook check out my VRS sensor air gap case study in Section 21.

[@ucnhtmenow1]

I put a crank sensor from a 2001 cobra that had a blown rod that got jammed in the crank and seized the motor, into the new motor that went into the car. I'm wondering if the crank sensor could have gotten damaged internally from the engine being blown, even though physically the sensor isn't damaged itself? The second type of crank sensor he showed (3 wire), I believe is what I have (although it's a 2 wire) but I think it's the same concept.

[@--gmoney5572]

Beautiful, Your good at the point. Looks like Tutankhamen wrote you a letter on Walters Whites Crystal..

[@Ranalla651]

These are all I need to look at to get my dis ford running. Will pico 2000 series 25mhz scope work.its not the 4k series automotive but it should still work correct? Also where can I get this book of yours. I am in MN so I cannot attend your class or I would!

[@felmar39]

Great video Paul , good bless you man , for sharing everything you know, thank you my friend

[@Username64870]

You have gifted talent man great work again!!!

[@stuzman52]

Thanks Paul for the reply!

[@ScannerDanner]

I was surprised by that myself. Codes could have been clear by the student before they brought it to me or maybe with the negative battery terminal being loose the PCM memory was resetting at times. Or it simply just didn't set a code. IT happens for sure.

[@sivucit]

you have told us before that if coil doesnt have RAMP it is shorted, but however i can see in this design there is no RAMP, it has a peak sudden, wondering why is it, i remember u told us that multi spark engine have such kind of characteristics. any advise, please... I also think this air gap wont be an issue for 2 wire magnetic AC sensor as oppose to three wire hall effect sensor, is my understanding right?.

[@zxtenn]

Is there a suggested airgap say for example .100? If there is a suggested airgap i assume it might be difficult to measure for it-- All you did was push in the CPS a little which probably didn't amount to much measurement wise and it was fine-- so it would seem distance is critical for it to run properly but difficult to measure/set

[@ScannerDanner]

I certainly wouldn't endorse using the same signal circuit integrity test on a wide band that I have shown on a narrow band O2. The PWM O2 heater circuits operation strategy would be vehicle specific. The main point with these is understanding the testing differences. In other words what would be normal heater power and ground voltage levels. See Section 5 "Oxygen Sensor Testing" in my eBook, under heater circuit tests. (if you have it)

[@mikeasadoorian8384]

ScannerDanner at a boy

[@ScannerDanner]

ouch, on the wrong converter bolt. thanks for the tip again!

[@KaldekBoch]

I wondered why that motor looked so familiar...then I realise it's a Mitsubishi 6G73. Handy if I ever need to diagnose similar issues with my 6G74!

[@flkeystowing]

great video like always, one quick question what do you use to keep your adjustment in place if you dont buy a new sensor?

[@Turbotomass]

Every time I watch your videos I see more and more the power of the scope. What scope do you recommend for a beginner?? Thanks.

[@michaelovitch]

Very interesting.

[@ussj4brolli]

Coolest damn video explaining this!

[@jplkenny]

he knows what he is doing, for sure

[@zxtenn]

Paul, i have a question regarding testing a coil/coils with an adjustable spark tester, since some coils may fire at say 20,000 volts but won't at 40 thus misfiring should voltage be researched as to what it's supposed to be from the factory before condemning parts and where would you find that info? I don't work in the field but with my hands at my job and spend time working on my Jeep ZJ, however my actual DX/electrical knowledge is limited so i enjoy watching these videos+ slowly learning

[@josephpingel2553]

Great videos. Besides the gap, what do you think is the affect of oil on the sensor as a result of a transmission leak into the bell housing. I've driven it for months without much trouble but recently it started misfiring more severely and my mechanic blames it on the oil.? Does oil interfer with the magnetic pull? If so, do you know of any fix other than a major repair?

[@ScannerDanner]

It doesn't but if the oil is getting into the sensor connector or if the sensor if cracked that can be an issue

[@josephpingel2553]

@@ScannerDanner That makes complete sense to me, as well as checking the connections. I'm betting on too big of a gap; the same issue you discover in this video. It's guesswork to some extent, but your videos give a lot of conceptual understanding to the overall problems likely to be encountered and their likely fix. Thanks again.

[@manishgaikwad1659]

Thank you 🙏🏻 sir for good knowledge information 😊

[@Amopower]

Without a scope, I bet you are right they would have done the cap and rotor, still had the misfire, then they would have put in a new crank sensor and it would have worked - only because the act of putting in the new sensor with the right air gap masked the original air gap problem. So the customer would have gotten charged for all three (the tech would have probably justified the cap/rotor somehow), when in fact should have only gotten charged labor.

[@ScannerDanner]

@beansandgravy1 thanks man. that really means a lot. much respect i have for you

[@clementlee428]

Hi Paul, i got a crank signal from a smart forfour 1.3l petrol with sequential of 16 - 17 squarewave signals. Is this what we expect to see from a crank signal? I would have thought that the signal should be the same as in this video you have 4X 4 square wave signals per revolution.

[@omarG19100]

@scannerDanner no thank you. you and eric the car guy are car doctors lol. Love the way you explain in detail as your goin alone not to mention at the same time filming it. just keep these videos coming.