Gas Gauge Not Working. How to test Fuel Level sensor

[@OzMechanics]

So I’ve always wanted to make something special for my 100,000 subscriber milestone. I know I haven’t got there yet. But like In Christmas and presents, I can’t wait lol. SO… let’s make this fun, and the subscribers that accurately count how many times I say “so” on the video will be entered in a raffle/ drawing to win a $100 gift card. Hope this doesn’t take away from the content. Just a little thanks to my subscribers that stick in with me. Enjoy

[@rickylivas5441]

P 0

[@rickylivas5441]

0

[@user-ej7pr9ys4i]

My fuel gauge reads full

[@jessmasters4117]

I counted 4 so's. This video lifted my spirits. Thanks Oz.😅

[@phyllis4804]

Just watched your video fro 5 yrs ago on relacing an inside door handle. They want to charge me 150 to 200 to do it and I think I can do it myself now thanks to your video. Will be watching you more often and thanks for the video. Its great

[@OzMechanics]

Make sure to get a dealership part. I’ve actually been having bad luck lately with aftermarket parts

[@fredsalter1915]

I like the low-rider bounce test!!! Great vid, Oz!!!!!!!!! Keep 'em coming please!

[@OzMechanics]

Just wished I did a screen shot of the scan tool. Thanks for watching Fred we are going to be coming out with some really cool videos in the future

[@timothyrehfeldt5709]

Bro... Very thorough troubleshooting. Well done. I'm impressed.

[@OzMechanics]

Thanks for watching. Glad you liked the video. Feel free to watch one of my favorite. It’s the 2 part camaro series. Look up car runs with out fuel

[@stanleyunderwood6501]

Excellent diagnosis, spot on. You nailed it. Thanks

[@brawksolid6285]

Thank you for the great how-to video. I learned a lot and quickly, too!

[@TheOmegaman69]

A good video, and a quick diagnosis. One suggestion I would make, or to respond to your invitation to answer what I would do, is that I would connect to the signal wire back at the tank, and then pull it to ground with a test light and see if the gas gauge goes to full, or close to it. This would verify that the 5 Volts, GND, and signal wires are all good before taking the gas tank down. Then, if it tested good, I would do what you did. Again, well done video and diagnostics. Thanks for making it. Omegaman

[@OzMechanics]

On this one I took off the bed that was fairly easy. And checked the resistance and when I saw that it was high I took out the fuel pump. But didn’t think of your way. That’s pretty good stuff. Thanks for stopping by

[@JamesAutoDude]

Wouldn't this potentially fry the computer?

[@rickcruz3737]

So I was counting then gave up! 😂 my daughter kept talking to me. I got a note pad and got 81 So’s. I also realized that I have to see the video again to pay attention to the whole thing and I also realized the the customer needs new shocks. Edit: Your videos makes the DIY’er understand it, in simple terms and clear to the point. Thanks!!! I got to say I don’t even consider myself a DIY’er. 😜

[@OzMechanics]

It’s awesome that you guys enjoyed the video Rick. I just can believe I said so more than 40 times on a 15 min video

[@spelunkerd]

I admire the way you guys are able to make diagnoses when it is so difficult to reach the suspect part. The conventional design is to use a simple voltage divider with an upstream fixed resistor hiding inside the PCM. A 5V signal comes through that upstream resistor in series, then follows the sensor wire to the second variable resistor inside the tank. Although they could design it either way, the conventional float wand is as shown here, where higher resistance is seen with an empty tank. That way if the wire breaks, the driver is told the tank is empty, which is better than being falsely reassured it is full. The PCM measures the voltage on the wire between the two resistors, so voltage is high when the resistance of the tank resistor is high, because there is more voltage drop across higher resistance compared to the fixed resistor inside the PCM. Here's a method to prove your upstream wiring is OK. Puncture the sensor wire as you do here, as close to the tank as you can get. Tap a grounded incandescent test light on that wire. Turn the key on and see if tapping the test light on the wire moves the dash gauge. Your test light won't necessarily glow, you're only using it for safety so it is not a direct short to ground, it's a handy 75 ohm resistor. Note that in new cars you may need to erase codes, like you did at the end. If the gauge moves, you've got strong evidence that everything upstream of the puncture is OK.

[@unclecowboy2003]

Can you use the new style of powered test light for this test

[@spelunkerd]

@@unclecowboy2003 There are rare indications for LED test lights, but most often the best lights are incandescent. Old school incandescent bulbs have lower resistance which means they draw more current and require higher voltage to turn on. By drawing more current, upstream or downstream resistance is easier to detect. Ideally when testing a circuit you want to test at the approximate current level that is normally drawn. So, LED bulbs might be OK for computer testing but for a fuel pump, headlight circuit, etc, you need more current. Most of us keep a headlight bulb in the tool box to drop test circuits that draw about 4 amps.

[@unclecowboy2003]

@@spelunkerd this is what I was looking for thank you very much for your help and time to respond

[@williamgallaher4566]

Great video extremely well explained. Thank you very much. Stay strong and be safe 🙏.

[@OzMechanics]

Awesome. Glad you liked the video William. I actually made this video because I made a bench tested one and subscribes wanted to see a test performed on the vehicle

[@rplayer9969]

You should have shown how far the tires were bouncing off the ground. My guess is a foot. L0L. Great video. Please keep em coming.

[@ebrahimsadeghi5883]

Awesome oz I love your Chanel Lots of fun and informative

[@TXNLIF]

Bro I need to take my 97 chevy truck to you...I've been having this issue since I bought it.....awesome video..keep up the great work

[@OzMechanics]

Glad you liked the video thanks for stopping by

[@davidgriffin14]

He just showed you how to fix it yourself. Lol

[@TXNLIF]

@@davidgriffin14 I know...but my truck has other issues..lol

[@leewalker3514]

Thank you for your information I know now what I have to do. Thats just one of mini mini mini problems with GM. Cars & trucks Thank you so much.

[@richardmitchell7836]

So...I counted 85ish LOL, along with watching the video 3 times to satisfy my OCD lol. I do the same thing so with that being said, I don't think I would have ever thought of shaking the truck so I learned a new trick. Thanks, Oz, always enjoy your content. Be well, my guy.

[@SchrodingersBox]

Oh dude I never knew you can do that gauge test!!!! I hope my Autel can do that!! What an amazing time saver! hey you are almost at 100K subs man!’

[@OzMechanics]

Yes sr. Hopefully by mid next yr

[@Kanal103]

Is there a way to test the gauge itself if it's older car and there's no way to do it like in the video with computer diagnostic tool? Something "mechanical"? I have this interesting problem with 2004 Daewoo (Chevrolet) Kalos. When I put ignition to ON I can see the fuel gauge to move a tiny little bit (just to say it is not "frozen" at all) and it falls down as well when I remove the key. I removed the fuel pump unit today and measured resistance and I am getting about 400 ohms for "empty" all the way to about 17 ohms for "full". No jumps, nice linear change. What would you suggest to do next? Thanks a lot.

[@specialtyentertainmentdj]

Similar problems, but i already changed the fuel pump and filter, and the gauge is still stuck at 1/4. I dont have the scope and am unsure where to take my truck for the repair? My regular mechanic doesn't do electrical.

[@porky7753]

Thanks for the video Mr Oz, when you was rocking the truck my mind went in the gutter with the hoods rats from the past.

[@OzMechanics]

I was going to add some berry white when I was rocking the truck. But I ended up scrapping it

[@porky7753]

@@OzMechanics 🤣😂

[@rayallen3036]

I have an 08 Silverado, 6.0. Changed fuel pump and realized I had torn harness wires due to the front drive shaft. I was able to rewire power, ground etc from the pcm to the pump to the fscm. My question is where does the purple wire from the sending unit connect to? Everything is working fine now but I dont have signal to the gauge...and the gauge does work because it was tested.

[@rjm7168]

My diagnostic computer will give me the fuel gauge voltage sent to the ECU for both the front and rear fuel tanks under the Live Data/Data 1 menu. Interesting that Snap-on does not. No need to back probe. From this Data, I found that the rear tank fuel level sensor was not working correctly. I did not get a code - just ran out of gas when the gauge said 1/2 a tank. BTW - my truck is a 2004 Suburban that uses the exact same instrument panel as the Silverado in your video.

[@advancedleveldiagnostics]

Great Video, I counted 79 so's

[@OzMechanics]

Is that your final answer

[@AngelHernandez-lv7xy]

So I got a question on my 2004 Chevy Silverado. My gas gauge actually works in reverse. Do you have any suggestions of what I should do to fix it

[@RockyPatrol]

Great video! Wondering how much it will cost to fix it by motor shop?

[@davidweum]

The gas Guage on my truck never worked properly in 10 years. My brother ran outta gas a couple times, but I never have. I have 4 gallons in a red 5 gallon tank in back. I just keep track of mileage and fill up when necessary. I don't bother with diagnostics even if I knew what I was doing.

[@Kevinb1821]

I have a similar issue with a 2005 mustang gt. It seems to only happen when I’m parked idling the gauge will drop to 0 and the dash will say data error. Then a minute later the gauge will work. Or when I shut the car off and on it will start working. I hear chevron Techron may help if it’s just varnish on the float sensor ? The car still runs fine but I hate having a check engine light on

[@Mr2004MCSS]

My 98 chevy truck has this same error code stored in the PCM and my gas gauge stays on full most of the time. When I come to a stop, it will sometimes go all the way down to empty. I'm sure it needs a new sending unit but I will just wait until I have to replace the fuel pump. I will have to try these tests to see if it's the sending unit for sure.

[@johnengland8619]

Thanks for the content

[@markchimmy]

Great video! Could you please tell me what could be the problem with my 04 lincoln town car my fuel gage reads empty after I disconnected the battery cables checked all fuses they're all good! Thank you!

[@petergarofolo9385]

Interesting video. 👍 👍

[@OzMechanics]

Thanks for stopping by Peter

[@sunyazdayz4848]

Help! I watched ur video. Well done! I did the same job on mine. Fuel Guage works only when it wants to. So never. It will flash me at start-up and then turns off. I'm not sure what it is!? A ground wire? How can I get a mechanic to do this job and not get taken to the cleaners.

[@shaunblakemore7150]

Great job 👍

[@OzMechanics]

Thanks for watching Shaun

[@unclecowboy2003]

Hi I’m thanks for the help to look at this problem I replaced the pump module and it ran fine for a day now it has the code again did I get a faulty pump and sending unit or did they give me the wrong pump module I’ll order a replacement and let you know it’s a 07 suburban

[@MikeSmith-nu9wt]

Would a 2000 gmc 3500 5.7 vortec ,hold a code ? I put in a new pump and unit , still nothing ? Gauge or wires or did I get a bad one ? I tested it with a ohms/ multi meter , but I didn't know the values , I never did check for 5 volts , I'll do that , next time it's on the hoist ..

[@user-ry6bs2si9h]

My 2003 diesel fuel gauge is doing the same thing, but no light. I confirmed it with my scanner. Could it still most likely be the sending unit?

[@trentonholz8677]

Ive had my fuel pump and cluster replaced and gauge still doesnt work. The gauges sweep with a scanner. Dealer beleives the next issue to check into would be a wiring issue from the PCM. You have any experience with that?

[@OzMechanics]

Check out pin fitment. Also look at the wiring and see what voltage it has on it

[@mrsanders6762]

What is have any affect on your odometer stand the second or third gear

[@javierservin2001]

Hey, how are you doing? What if I change the fuel pump in the gauge goes bonkers the fuel gauge worked before I change the fuel pump the reason why I changed it was because it was the engine was hesitating so when I change the fuel pump, the gauge went all the way around almost, but the low fuel level light would be off until the fuel level got low enough for it to come on now it stays on. What do I do?

[@AngelHernandez-lv7xy]

If I put in a new gauge cluster, does it have to be programmed or can it just be plugged and play?

[@robertbyerley1188]

I have a 2004 GMC Yukon and I thought it might be the stepper motor so I replaced all of them. But the gas gauge is intermittent and will go to empty and later back to showing a reading. Now I have a cluster that intermittently goes black. Any ideas would be helpful

[@johnettewitham4845]

I have a 2005 Chevrolet Silverado 1500 crew cab ls 5.3 v8 LM7 with the fuel gauge stuck on empty but I have put 2 brand new fuel pumps in and the fuel light was still on but the problem was the flot was to long on the new fuel pump so I taken the old flot from the old fuel pump and put it on the new fuel pump and that fix the problem for almost a week but while driving I look at the fuel gauge and it shows empty but there was no warning saying fuel level low and as well as I had the gauge cluster rebuild and so now my fuel gauge doesn't move but some times it go up little bit and go right back down to empty and if you turn on the key it doesn't ding saying fuel level low.

[@johnnylorona3361]

Mine is the same. But mine starts and dies right away. Why would it do that

[@johnnylorona3361]

My question being if the gauge stops working will the pump still work. I figure if the gauge marks empty the brain won't let the pump do its job no matter how much gas is really in the tank.??¿??

[@goodwill_ken]

Cheers lad!

[@DavidGutierrez-zi4dy]

hello! I use a resistance substitution box and interception the purple wire connected in series to ground and move the knob to check the circuit .pasadena texas

[@OzMechanics]

Awesome. You’re also in Pasadena tx ?

[@DavidGutierrez-zi4dy]

@@OzMechanics yes .we meet at pls on Spencer and shaver..almost 2 year ago.

[@gregm4159]

I got the same code as the one in the video should i just replace the the pump

[@officialcheeze5853]

do you know whats wrong when the gauge goes up and slowly goes back down?

[@ididntdoit8721]

I have a fuel gauge problem i bought a new fuel pump ND changed the old one still have that problem it's a 2011 jeep liberty all fuses are good 3.7 v6

[@FelixxDaily]

Does the engine light flashes when this same problem happens?

[@arnulfoesparza601]

Hi there. Question what if the gauge spins around?

[@jarrettmims452]

Man I definitely need to get me a scanner. My fuel gauge temp and oil pressure gauges don't work. If I have turn the key I can see the message board miles and all that but soon as I turn key it goes away and then the three gauges don't work.

[@photondebuger45]

Yeah i did that with my gauge too with a scanner it didn't go all the way but it moved when I turned it on and off.

[@marymcd6997]

What would be solution for 2015 Duster Fuel Gauge showing empty.?

[@troytalks4444]

How much would this normally cost

[@ebrahimsadeghi5883]

God bless

[@franciscocrcabrerar9028]

Change the sending unit twice ,new gas tank as well on my lincoln mark v, gas still show half full when is full😢

[@brantray6774]

I have a 2017 GMC Sierra 1500 that reads low fuel intermittently. Once I start driving, it will correct itself. I guess I need to look at getting a new sending unit, I guess.

[@OzMechanics]

Time to pull out a meter to see what’s going on on the voltage side

[@feaoteulilo]

🔥🔥🔥🔥🔥🔥🔥

[@froy204]

In other words you need a new fuel pump

[@OzMechanics]

In other words… yes 👍

[@starshaallen45]

What if you just replaced it at the beginning of the year 🥲

[@1askingforhelp]

​@@starshaallen45could be a bad ground

[@Fatpumpumlovah2]

Yeah all that rig maroll talk for same conclusion in the end

[@Chinesec742]

No just the Floater

[@scuba422123]

a decade box works too 20 to 220 ohms range gm says its the alcohol we seen that for years in the north east hope all is well oz ive seen you on marios interview techs just dont get their worth nowadays i think thats the shortage

[@Ch_ozz]

How can I message you directly please I’m having fuel gauge problems in my 2006 Chevy 3500 gasser.

[@PappyNet01]

Thanks, but for a older vehicle such as my parent's 1997 Monte Carlo LS I have often been told by auto shop mechanics that it isn't worth repairing due to the age of my parent's car: the fuel gauge has been dysfunctional for a very long, long time. I drive the car more than my parents and I do the same as my Father - when the mileage-gauge gets to 250 miles it is time to buy more gas. I wish there was a easier repair option! I was hoping I could find some kind of wireless float that I could toss into the fuel tank and it sends a signal to a USB plug-in receiver in the lighter? What year is the truck? I also have 2005 GMC Sierra 1500.

[@JamesAutoDude]

It's always worth fixing a car if it's what you're going to keep using/driving. Don't listen to anyone about it not being worth it. They're talking about if you plan to sell it which you will never get back what you've paid over the years so, who cares. Just fix it so it can be used and don't worry about resale value

[@marianochavez7146]

You know your stuff my respect bro and snapon tool awsome

[@user-if7fn7rk2w]

So I have one I just replaced fuel pump in and now gauge is stuck empty. I can pull pump out and move gauge manually and the gauge moves. Put it back in tank and it reads empty. I’m lost

[@aymenmohamed1134]

👍🏻👍🏻👍🏻🌷

[@chadgardee1496]

Do a sweep test on it

[@OzMechanics]

I did. It’s in the video

[@user-2Hteyasizyc]

Now you just need all new shocks after the repair sir! :)

[@OzMechanics]

Putting some new fox shocks

[@lancemoore6966]

Just put a new fuel pump with sending unit in my z71 tahoe and my gas gauge sits on empty with the gas light on and other times it sits almost on 3/4 and doesn't get any higher than that at all

[@orinmangar2333]

V=IR. Voltage is equal to Current times Resistance.

[@tracymurray9798]

I think I'll set my trip meter when I fill up

[@richardcranium5839]

lol@ bloopers. maybe a few less energy drinks ???

[@shanewalley891]

Or just set trip meter to zero when u fill up most all 5.3 get 400 or 375 miles to a full tank

[@ronalddill6540]

Where are you located?

[@OzMechanics]

I’m in Texas

[@ronalddill6540]

Do you have a video on fuel gauge that won't go all the way to full. I had my instrument cluster rebuilt for this issue and some others. It gets closer to full now, but still not all the way.

[@reygiron8312]

Just change the unit save all that

[@OzMechanics]

What happens when the fuel pump goes out? Have to redo the job

[@donnellbaxter8050]

What if the fuel gauge stuck on full.

[@jeremydigiammarino9617]

Check the ground wire

[@CravinMorehead420]

80 "so" and 1 what"SO"ever 😂

[@OzMechanics]

Hmm 🤔

[@johnderryberry8456]

So, do you ever clean your fingernails?

[@OzMechanics]

I do, but I get them dirty again once I start working on cars. Thanks for stopping by

[@mikesautomotivediagnostics8080]

So, I counted 74 So's. Probably missed some. LOL

[@OzMechanics]

Hmmm sooo you might have to check it out again

[@mikesautomotivediagnostics8080]

Went through it again and heard 81 So's. Nothing like a little game to waste my time. 🤣

[@mikesautomotivediagnostics8080]

I could probably go through it three more times and get three different numbers.

[@bartscave]

So another GM fuel module!

[@patbfd]

81 or so

[@danman9017]

79 time with bloopers

[@OzMechanics]

Mmmmm you sure

[@danman9017]

@@OzMechanics lol

[@lyndamenyweather9678]

Man what’s your contact information?

[@charitymitchell1976]

this is way over my head....

[@OzMechanics]

I tried simplifying as much as possible.

[@ricklesperance1401]

I know what is wrong with it. The shocks are bad.😅

[@carelectricmaster6380]

Which volt input fuel gauge

[@OzMechanics]

Comes from the pcm.

[@senorjalapeno3937]

I removed the code on my truck too, and the gauge was still showing empty