Troubleshooting Oil Pressure and Water Temperature Gauges

[@jimnjele.bean-dayone3505]

Love this video. Straight to the point, no music, long intros, or other bs. Thank You.

[@tuske427]

This video is EXACTLY what I need to understand how to diagnose my friend's 1968 Firebird 400 with rally gauges I installed and aren't working yet... THANK YOU SO MUCH for making this!!!!

[@asiasmaster]

Hello, my 67 firebird oil pressure gauge reads 100 psi the needle moves just barely once shes at running temp. and I tap the throttle, my oil pressure sensor has a fitting with the tube attached to it. How do I correct this issue. Ty

[@sollykhan2385]

Concise, accurate and to the point, no B.S or nonsensical intro's, loud music and other undesirable nasueating drama that may require Medical treatment in the aftermath!! This is THE ONLY WAY to disseminate factual scientific training. Thank You Sir 10,000 stars *** and a free Big Mac with fries,,for Life 🍔🍟 🙂👍

[@OverTheEdge68]

What a difference, a actual Technician sharing his knowledge of Diagnostics and repair. Nice to watch a true educational video for once. Most info these days, seems to come from a R&R perspective. Thanks for the refresher! Peace!

[@deankay4434]

The video is from the manufacturer called “Auto Meter” who has a department for animation. Even then, hooking to the battery is wrong! It is a variable resistance to ground the makes it work. ASE Master tech, 78

[@erichelff7256]

Note: At 2:26 - that shows the connection going to the *wrong* battery terminal! It should go to the black (ground) terminal on the left side of the battery-- not to the red (positive) terminal. Great video otherwise!

[@psa10hunter94]

I noticed that as well, other than that it’s very helpful, thanks.

[@deankay4434]

You are correct as this is a variable resistance to ground not B+! ASE Master tech, 78.

[@jaykellywood]

Thank you so much for this video!! I had to watch it about 9 times before I actually understood what was happening. I took the information from this video and fixed a problem I was troubleshooting for 2 days. Turns out the wire from the sensor was cut so I spliced it together and the new replacement gauge was bad. I put the wire to ground and it didn’t move at all. I replaced it with another gauge and it worked! Thank you so much!!

[@conradsugden4599]

Thanks. I'm a learning diy mechanic and this helped me to diagnose heaps

[@robertmcdonald4668]

Thank you for this. I installed aftermarket gauges, using the senders that came with them (swap meet purchase). Wasn't getting any readings from oil and temp. Tried the ground trick you show and learned I had a loose connection at the back of the gauge. I was ready to order a different set of gauges, thinking it was broken.

[@matth7090]

Thank you, I needed to diagnose an issue with my oil pressure sender. You helped me resolve it without buying another (I did indeed use a sealant, so it wasn’t earthed to the block! Great advice)

[@mercman1958]

I did this test on '63' Mercury Temp gauge. One second after hooking up ground to gauge wire, the gauge began to smoke after it jumped to 'Hot". I turned off the power the second I saw that. Thankfully the gauge still works. Almost ruined the gauge following this video! :(

[@lemontier]

I believe that his test was for the sending unit not the gauge.

[@darrylyoes414]

Careful... Direct grounding sensing wires can equal BIG currents, and at best end up with blown fuse and at worst melted wiring. This is not a good test method at all.

[@GrantArdern]

This is the best video I've found explaining this stuff - good job - very helpful!

[@cutl00senc]

Teflon tape fills the voids in the threads of the sending unit to prevent any leaks. The majority of the tape doesn’t stay in the threads and thus metal to metal contact is sufficient enough for a decent ground to occur.

[@DougieeStyle]

But being a tapered thread it will seal its self with sufficient torque this eliminating the need for thread sealant, using it would just be a cautionary measure

[@MikeSsuncoasttrains]

Not in a v8 boat engine. Teflon is absolutely needed.!

[@deankay4434]

No tape, use liquid PTFE thread sealant as directed by the service manual.

[@3wamy]

Thank you a lot you really solved my problem. I was insulating the ground by some teflon tape.

[@Madscott]

This helped me fix my temp gauge on my C10 today. Thanks!

[@johnmcdonald1293]

Thank you yes Teflon table used on the thread an insulated the Earth which interns stop it from working.

[@howardlovecraft750]

Now that's one good way to make an instructional video a lot better, be good if a lot more KZbinr's out there make their videos following the led of this one....you just got a new subscriber here after watching this one.

[@bryanmccauley7913]

Great vid. I have a 78 Ford F100. Can you tell me what the connector looks like that the sensor wire plugs into? The connector that goes into the firewall. Thanks!

[@samsixkiller3270]

Thankyou perfect and very concise not rambling on which is great.

[@MinnesotaClassof]

Thank you! It was the teflon tape.

[@billgraham5609]

Thanks, that what I needed for an old CJ Jeep

[@greggwilliams116]

Maybe you can figure this out, 70 Pontiac oil water temp gauge I hook the sending unit to neg on battery leaving wire harness attached to sending unit and temp gauge turn on as instructed in video but the fuse blows, if I use a tester light and simply check power to the sending unit from wire harness it has power but can't reading at gauge, have tried 3 gauges. Any thoughts

[@phigo4kins]

How do You also Use this test in Modern Cars? 2005 Chevy Impala. Also, since they are directly connected, can a Faulty Coolant Temp Gauge cause/mimmick Symptoms of Bad/Faulty Engine Coolant temp Sensor? I'm chasing a P0117 Code.. Thanks.

[@jeremiahm1413]

Great explanations and picture diagrams. Thank you!

[@10MinutestoRouletteFortune]

Am I missing something or did he ground the oil sending unit to the positive on the battery? 2:30

[@kitejake]

Oregon's Lonewolf seems very strange at one point the red is positive and the next negative....

[@vernonsteinkamp1088]

Yea, I thought wow, that would get the gauge.

[@spudsmckenzie4123]

They also mention oil "temperature" and "hot" when talking about an oil pressure gauge. But I would listen to the narration over the images.

[@jayway3676]

You forgot to metion improper level of coolant. If it is not going to display proper readings. Huge difference between ambient/steam air and direct contact of hot fluid. Just thought to add that in for you.

[@rockabillydreamer]

Actually it would be great to understand how the inner circuits of the electric water gauge work. I see that mine ( a stock 1958 Plymouth unit) has under the screen two micro coils with a microscopic wire wounded around and some other misterious tiny levers.....The two micro coils are connected one to the positive connection of the instrument and the other to the sender connection.

[@Como651]

In idle my temperature gauge reads in the middle. As soon as I drive it pegs full hot. I replaced the sending unit and it still does it. If I have someone wiggle the wire to the sending unit thinking it will create the shirt I can’t get it to peg. What’s going on? 1988 Suzuki Samurai. All started after rebuilt motor swap.

[@christiancallaert3313]

Thanks a lot. Do not use teflon!! 👍🏼

[@MartinSage]

I disconnected the wire and grounded it. Turned on ignition + needle shot up to hot. Need to replace sending unit.

[@justinchristiano7928]

Awesome. Thanks. Solved my problem immediately!!

[@rockabillydreamer]

wow this is very useful! Very simple and easy to perform . Thank you very much !!!

[@johnwhite192]

Thats awesome man and yes it will improve gas mileage because when you're temp goes below normal the computer puts it in limp mode and everything is messed up then mine idles really high when it happens so it definitely hurts gas mileage. I have 03 Ford 2.3L ranger i replaced the cluster it did help i went from 50 miles to 80miles drive 80 miles temp goes zero everything coolant wise is new. Really driving me crazy and killing me $$$ wise shop has truck more than me. But i think im still going to let them figure it out. But curious if the cluster switching fixed your problem?

[@deankay4434]

The PCM dumps extra fuel to a cold engine for enrichment taking the place of a choke.

[@DanielOrtegoUSA]

Helpful information, so thanks for posting.

[@violetknight6427]

I replaced both my coolant temp sensors on my 94 K1500 5.7L and replaced the thermostat and housing and basically flushed and burped the system I should have tried this diagnosis first hopefully it’s just the dash I hate doing wires.

[@walterdowns9978]

If I disconnect the wire from the sending unit and hook a multimeter from it to the positive on the battery I am thinking there should be 0 volts when the car is off so what I would like to know is what voltage that would read from the temp and the oil sending units when the car is running and warmed up

[@Supanova70]

When there is no info on ohms readings from manufac. how do i know the right fresistance values at room temp to test sender. That is what i was looking for to solve a overheat.Chart?

[@joedon1706]

Shaking my head. Power goes from key switch to the gauge. Through the gauge to the "sending unit" which is actually a "receiving unit". A ground. I am correct? When the water heats up the ground is better and more current flows to the the receiving unit. So when totally grounded the gauge reads full hot. Correct? Something does not add up with this video. Thanks.

[@mercman1958]

One second after hooking up ground to gauge wire, the gauge began to smoke after it jumped to 'Hot". I turned off the power the second I saw that. Thankfully the gauge still works. Almost ruined the gauge following this video! :(

[@deankay4434]

The manufacturer “Auto Meter” incorrectly shown the wrong wire connection in the animation. Power is supplied to older analog gauges as it is a variable ground controlling the strength of a magnetic field inside the gauge to push or pull the needle for proper readings. At the dealer, key on, engine off, unplug sender and gauge drops to zero or cold. A box containing a variable resistor like a potentiometer will show movement it gauge & wire are good, but grounded, it simply goes hot or full. The fuel is a wiper on wire wound resistor while temp uses a negative temperature coefficient thermistor, a solid state device that changes with temperature. They make positive and negative both in different range values. ASE Master tech, 78.

[@Rainaman-]

Thanks! Helped me with coolant gauge

[@timlamacchia7070]

I am trying to troubleshoot my volvo penta gauges,sensors and wiring. a few of my sensors have two wires connected to them. what is the process to test two-wire sensores?

[@Samson-EC]

Hoping you can assist. Replaced my temp guage sensor. Chkd sensor first, chkd wire to sensor and chkd guage per your instructions. Everything chkd out. Temp guage was normal before but now it reads max hot for some reason. Not sure why. I can put old sensor back in since it tested ok to see what guage reads but I hate to pull it again. Any ideas appreciated..thks..jc

[@M3Atelier-Initiative]

@2:28 your graphic and audio says grounding the sending unit wire with the graphic reading (negative) but the image show it going to the (positive) post. ( SUPER FRIGGEN CONFUSING DUDE. )

[@bradmaccalla6020]

with the engine running at idle it shows over the top over heat. rev engine up to 2000 rpm and it drops to 140. decrease rpm's and the temp goes up. battery disconnected, needle is all the way up......Bad gauge?

[@BAHRacingTeam]

Does the liquid tape cause the same issue as Teflon tape? My electric oil pressure gauge goes to full high when power is introduced.

[@AlanSchildroth]

What happens if it starts at like 160 when you turn the key on?

[@SunnyDaysRFun]

So what does it mean when I ground the temp. gauge wire and it buries the needle on the cold side?

[@tinker0000]

In theory. If I have a temperature gauge that reads higher than actual, I could add a small resistor to the wire to drop shown temps?

[@robertmccully2792]

Or remove the indicator and place on correct number during a know value.

[@Steuspeed]

Your graphic is incorrect for grounding the oil pressure sender for testing the gauge. It shows conniecting to the red positive terminal of the battery, althought your graphic has a '-' on the blue line.

[@eaglewatchproduction]

When I hook up Sending unit wire to negative (-) side of the battery nothing happened. But connect to the positive (+) side then gauge is working. Wonder where is my car mess up would be? Any suggestions appreciated.

[@cloudrehzii]

Cutlass rally temp gauge is past hot ! I add the ground and it moved like 2 cm forward but when I unplug it it still stays where it was before

[@michaelb.7800]

Okay what year make model engine do you have in the Cutlass

[@cloudrehzii]

@@michaelb.7800 1985 442 5.0 307

[@michaelb.7800]

@@cloudrehzii If you would be willing to I can walk you through exactly what you need to do to test and Rule out each segment I'm going to go out on a limb and say that you have a multimeter does your multimeter have piercing capabilities and if so what you need to do without shredding your wire check for your reference wire your ground once it is unplugged from the temperature sending unit once you've done that if that comes back clear and your reference check and wiring comes back good let me know we'll go from there I can always give you my number privately and it would make it easier for me to send you pictures and diagrams and the actual and oem schematics that you need for your vehicle

[@scottbakas7372]

Awesome vid one of the only ones like it and super helpful

[@MariaGonzalez-ei1pv]

My temp sending unit was leaking ,so I tighten it as much as I can n still leaking had to use teflon, I didn't wanted too, .

[@elyoj6845]

Water temperature sensor = coolant temperature sensor? ~ I'm guessing.

[@T1GEVERETT]

Adding to homepage. Thank you

[@RMORT54]

Question: is it normal for the sending unit for water temp , to read a 0 resistance ( to ground) on a cold motor .

[@juanmartinez-kg2nz]

This was a lot of help thank you

[@masix73]

And me wondering why my gauge is reading poor… I used teflon tape

[@PACEDARTO]

excellent tutorial greetings from indonesia

[@lemontier]

Does the gauge care if the car is actually a positive ground like a Model A Ford? Or are there positive and negative ground gauges? I am trying to repair an aftermarket antique 1920s temp gauge that is missing the sending unit. An obscure manufacturer with no information available. Thanks for a great video.

[@estaworks-3d102]

positive ground doesn't exist. the 2 words mean the opposite.

[@lemontier]

Thank you for your reply. I have a 1929 Dodge and a 1930 Ford. both cars are positive ground.

[@jefffrayer8238]

@@lemontier The John Deere 2 cyl.,, at least all the letter series also had positive grounds. Noted in owners and service manuals.

[@faroukalmili4515]

That's what I'm looking for. Thanks so much.

[@seahunt2001]

If I don't put teflon tape on my sender threads, it leaks. So how do I keep the sender from leaking? I'm afraid to really tighten the sender a lot and strip the threads with it being brass.

[@stanbarrington9698]

Apply a short layer at the very top of the threads.

[@walterdowns9978]

2 mistakes I think you made in testing the oil pressure 1 You said connect the oil pressure sensor to the ground on the battery but your diagrams showed you connecting it to the positive. 2 You said connect the oil sensor to the negative and ( REMOVING THE SENDING UNIT WIRE ) ?????? Then how would you get a reading on the gauge?

[@jimmyhardison2630]

What is up with the background noise? Sounds like people on a 2 way radio

[@10susan10]

Per your own description of the testing method the so called "sending unit" is not and has been miss classified for decades. Increased reading on the gauge is from increased current flow FROM the gauge to the sensor.... NOT the other way as you describe at 1:05. Heating the coolant sensor decreases the resistance to current flow. Same happens with the idiot light when it gets over a set temp the circuit resistance drops to zero & connects and the red light comes on.

[@DH-fc2os]

Hey everyone I'm looking for a little help trying to restore my wife's 68 Camaro finally got most everything working again and running , one problem I'm having is as soon as I turn the key the temp light on dash comes on and stays on. Car is not overheating and runs great. Now you would think the temp sensor but for the life of me I cannot find the temp sensor there is nothing on the block or on top of the coolant thermostat housing. Any ideas ? It should be located driver side between the block or head and the master break cylinder. Please help

[@stanbarrington9698]

Check the intake manfold!

[@DH-fc2os]

@@stanbarrington9698 thanks I will check there we believe the engine was changed out to a 350 ,. I will post a video of it tomorrow and see you or someone can help me with it thanks

[@stanbarrington9698]

@@DH-fc2os there is a port on SBC intake manifolds for sender mounting

[@DH-fc2os]

@@stanbarrington9698 thanks

[@Whelessry]

The sending unit wire, is that just a positive wire connecting to the gauge? My gauge has a wire that I THINK goes to just a sending unit and one that is connected to gauge and ignition. The one that I think is sending unit wire is Tan. Should I tap into that one for an aftermarket sending unit? I have "lost" the original plug during an engine swap. I'll have to wire itfrom the sending unit wire to gauge. Someone please let me know what you think!

[@cossee]

Very informative, great site

[@dannymarshall4826]

Do you test it off the battery in the car or on a different one

[@bradmaccalla6020]

With engine cold, temp reads over the max.

[@cmleoj]

Same with mine. I think he’s saying there is a break in the wire, causing the circuit to ground which makes the high reading.

[@photographer-ordinare]

This was crazy helpful!!!

[@taylorandtyler11]

So I grounded the temp sensor, which made the gauge max out, then removed the grounded wire and the gauge went back to zero. However when I start my 69 camaro the temperature still isn't reading on the gauge. I don't have any thread locker on the temp sensor. The ground test you instructed that I followed demonstrates that I don't have a break in the wire or a faulty gauge yet it still isn't working. Any more suggestions?

[@davidjauch6682]

Taylor Axdorff yeah, measure, then change the sensor?

[@taylorandtyler11]

@@davidjauch6682 Yes, I have changed the temp sensor and it still isn't working.

[@davidjauch6682]

Taylor Axdorff okay. So you‘ve tested the gauge, the wiring to the sensor and the sensor which you swapped out has ground. Did you measure the replacement - maybe a dud, although unlikely? All I can come up with is verify that the sensor is grounded and make sure you have coolant in - sorry.

[@taylorandtyler11]

@@davidjauch6682 Ok I'll double check the sensor to make sure it's not a dud. Thank you. I do have another issue - my oil pressure gauge maxes out everytime I start the engine? Though the oil pressure is not actually high as we had the engine tested prior to putting it in.

[@estaworks-3d102]

@@taylorandtyler11 old comment but. make sure it's the right temp sensor. if it's a sensor of too high resistance then it will only read cold.

[@larz46north18]

551k views and at 2:30 the diagram is WRONG.... red is USUALLY +

[@ImVisualz]

My water temp goes from low, to at about 110 when fully hot. Gauge goes to max when i hold the wire against a ground. I already replaced the water temp sensor. What could it be.. im lost

[@JH-tk6ge]

awesome video! Thanks!

[@PrimericanIdol]

lol. Water... Should be called "Coolant" temperature sensor. No one in their right mind runs their system with straight water in an everyday driver.

[@estaworks-3d102]

you'd be supprised. seeing as it was PERFECTLY FUCKING NORMAL back in the day. these days though everything is made in such a way that it would break if you did. and everyone is forced to pay 20x as much as you should for a mix that's litterally 80% or more water and some chemicals. and then there is the stupidity of people. people that fill the coolant resovoir up with pure antifreeze.

[@PrimericanIdol]

@@estaworks-3d102 People still refer to digital video recording as "filming". Some anachronisms are annoying.

[@MikeSsuncoasttrains]

Oh yes I do .in my boats in the river or lakes. Raw water cooled!!

[@Bill8DebTravels]

Thanks great and to the point!

[@Samson-EC]

How do you test the wire going to the sending unit?

[@Samson-EC]

So do I put one end on wire and one to ground from multimeter?..thks..jc

[@Samson-EC]

Thanks for the response. I have no idea where the end of wire goes to.....jc

[@letsthinkitover1]

It's ciadt a lot to have them test it so I just buy it and it's cheeper if it solved be. problem but if not them time to get help.

[@CaptConvent]

Very helpful!

[@funcars_]

this is gold 🙏

[@kikohandumon2438]

Thanks Bro❤

[@runbou3019]

អគុណបង

[@Jeff034]

thanks

[@HarryZaildaar]

Tnx

[@AymanBishara]

good

[@mr.lawrence6627]

kill the intro!

[@rnott5768]

I found the video not very informative at all. I might help someone who knows nothing at all about gauges.

[@SunnyDaysRFun]

So I grounded the wire and it buried the the temp gauge needle on the cold side. What's up with that?

[@nursecuenca]

My temp gauge only move a quarter when ground. Even on hot day it won't move gauge pass a quarter. Any suggestions?