Diagnosis of Stuck Fuel Gauge- Is it Gauge or Sending Unit? 

I believe your efforts to help others has eternal rewards.

Matt your are so darn Awesome... most Mechanics would have swapped out the sending unit .. but you are a true Pro... your not a part swapper ... Your a Parts FIXER.. you know your stuff my friend. 2 thumbs up !!

We need more honest compassionate mechanics like you !

We need more people like you to help us who is on a fixed income. May you receive many good blessings 🙌.

Very well done bit of trouble shooting. As a retired US Navy Diesel Engine Inspector my job was mostly the trouble shooting. Your methods both of step by step 1 thing at a time and the clear easy to understand way you presented it we're excellent. Love the resistor and will probably use one when I get to testing my stuck on 1/4 fuel guage. That you go the extra mile to help others is to me a sign of a good person with heart. As one of to those seniors I Thank you.

The fact that you wanted to surprise this guy with a bonus fix.. shows your brilliant colors of goodness and brotherly love. You set a fantastic example for all those who are fortunate enough to witness. I for one, am proud of that example. May you be blessed in many ways. High five!

I actually learned three things. 1. How a sending unit works. 2. Some molecular biologists are vehicular psychologists. 3. You're pretty cool.

Dude.. you are a gentleman and a scholar. Very wise format. I have absolutely subscribed. I appreciate your in depth presentation of the issues that we sooner or later face. Thank you very much.

Thank you for helping out someone on a fixed income and just being a good person. Hard to find in this day and age. I too am disabled now from a bad accident involving getting run over by a forklift at work..I was a truck driver..I used to do all my own maintenance and luckily had a father who went to school for auto mechanics way back in the 50's. He owned and operated a 10 bay repair garage and machine shop for 25yrs. His training to me has been invaluable over the years. Even in my current condition I still help all my retiree neighbors with their vehicle and other mechanical issues with what I am able to physically do. Makes me feel better about myself, and I don't even care if I get paid or not. Just feeling useful in society and good self esteem is better than any pay...you know what I mean.

This world needs kind, compassionate, generous mechanics like you, despite the work involved.

a video so full of love , thank you for helping your brother. Life will pay you with happiness ,thanks for for the video and for helping all your brothers. you a good bro.

Hi there… Mine showed signs of failure some month ago.I took it out and saw there was a cut wire on the sending unit.soldered it and thought it was it.seemed it works fine for some Klms but suddenly fell on empty again.thought it did break again but when took it out again soldered wires where ok…cleaned it , changed the plastic damaged cover of the upper plug tried it 2-3 times and it does the same thing.when I put key on it seems fine but after a few mins drops bit by bit to empty.wtf??anyone any ideas?

Thank you for your video. When you removed the sending unit and opened the box containing the variable resister, I was inspired to do the same thing. I was worried about contamination, so I sprayed the resistor block and contact point with carburetor cleaner to remove any varnish. Then, I sprayed the resistor block with the spray can electronic contact cleaner. After I did this, the resistance reading were perfect. Unfortunately, this was not the cause of my fuel gauge failure. My neighbor and I discovered that the brass float had developed a hole and was filled with gas. No matter what level of gas I had, the gauge would always show empty. Now, I know why. Found a replacement float. Installed it and the fuel gauge works now. Life is good!!

I've been trying to fix my sending unit/fuel gauge/something else for two months. I got some new tests to do in this excellent video, and tomorrow is saturday! Now that's a good time to be alive! "Sorry, I couldn't RESIST" LOL

This may not have been for my vehicle, but of course I needed to say how awesome that you are helping this man. This is a true example of human kindness. May you receive many Blessings in return.

Excellent video. That for the suggestions!

Hey Jesus Shuttlesworth I replaced the fuel pump and sending unit in my daughters truck. I removed the 6 bolts holding the bed on and disconnected the rear light wiring harness. Then slid the bed back about 2 feet. way easier than dropping the tank.

Hello Matt, I realize this is a bit of an old thread but still relevant. Love your Video's and I just came across this one. I'd like to share a bit of info with you and your viewers that may be of help in the future. I used to do a lot of electrical and electronic service and repairs. With variable resisters / brush contacts that were faulty and giving erroneous or no readings, I found that by using an electronic contact cleaner, an old used and soft green scrub pad and also 2000 grit wet and dry sandpaper will do a remarkable renewal of the contact surfaces. First make sure the rotating part is moving freely. Trim the sandpaper so it fits and slides under the brushes, wet it with cleaner and gently slide it back and forth to renew the contact surface being sure not to lift or bend the brushes. Then wet the fixed carbon surface and gently use the green pad to rub it down. Finish off by spraying off all residues with the cleaner and test for smoothness and variable resistance. Q-Tips also work good on small brush contacts. Cheers

Outstanding video. Very helpful. I just had a new fuel pump and filter installed on my 2008 Tacoma, and the fuel gauge is now stuck on full. Here's hoping they honor their 3-year warranty on their repairs! Thanks for the great video.

Great and interesting video (and intro of course)! I like your trick with the resistor, trying to emulate the sending unit. If you have a resistor lying on the bench and do not know the resistance value of it, you can always use your multimeter and measure it (no need to learn the color coding schemes). Then it is convenient with autorange function of the meter.

do u have to disconnect battery when changing fuel pump or sending unit ???

Thanks a lot for your intelligence, your method and your wish to get to the roots of everything. You're not only a good mechanic, you're also a clever and well balanced mind.

After not having a working gauge over 7 years, likely because he was afraid to see what it would cost to repair, to now a fixed gauge, I bet this guy is a customer for life and will be sending everyone he knows your way. This sort of fix will repeatedly be appreciated because we are usually looking at our gauges every time we drive. Molecular biologist? Chemistry major here.

Full of so much humor...molecular biologist indeed. Thank you for this video.

This is great! I'm a "try and fix it myself" kind of girl and my fuel gauge is giving me strange readings so I'm going to have a go at diagnosing the problem. Thanks so much for sharing the knowledge!

Best video on this topic I've found been searching for 3 days love it love it love it thank you so much

My gas gauge isn't working.

Okay, so I watched this but I don't know if it pertains to my vehicle. 2005 Pontiac Montana Base. The fuel gauge stuck way past the full mark after I filled up my tank. I had reset the trip meter when I filled up as well and at about 320 miles the Low Fuel Light went on. (horrible gas mileage driving in town) Anyway, since the low fuel light works it seems to me that the sending unit and float are working. What other issue could it be? Also, all other gauges on dashboard are working fine.

At first I was surprised to see very experienced technicians go right for the sending unit, rather than testing first. Then I realized how hard it is to get there. They don't want to waste time searching for wires under the hood, and of course they argue that the culprit is usually not the gauge. Watching your videos is a refreshing look at what you can do when you have more time. Those guys never try to fix, or rarely even test a sending unit near open gasoline. Having the customer pay to replacing the unit is done to avoid conflict that may damage the shop's reputation.... Great video!

Sooooo you’re saying my mechanic is a idiot? Eh, I agree. Kinda funny because I worked at a garage when I was 15 and learned WAY MORE than what I ever thought possible. Also learned the names of other local shops that were COMPLETE CON MEN. Fortunately, guys I worked w were EXTREMELY honest. Witnessed MANY times where cust had just a blown fuse and our guys just fixed it and said “$1 please”.. We were always busy because of this “honestly policy”, not to mention the cases and cases of beer that piled up in the back from “THANK YOU” gifts for NOT screwing people.

Hi there I hope you can help me,I bring my 2010 ford escape to ford dealer because of fuel pump recall after 1 day I notice the reading of my fuel,fuel gauge and mileage goes higher,the next day on my way home from work it stop on the freeway without warning,ford towed and fix it for me because part of it is there fault n my fault is the car doesn't have gas which is I didn't know since the reading is not correct,when I pick up my car for the second time on ford and put 30$ gas the fuel gauge is still stuck on empty,what do I have to do,tired of calling ford and I'm searching on website how much to change it nd it cost 2 weeks of my paycheck,can u help me

You're a hell of a good guy ... congrat's & thanks for this video. I've, pretty clearly, a gauge problem: ('82 Mercedes 240D)-- 1. I opened instrument panel (for bulbs/oil gauge line, etc., work)... 2. after reassembly, gauge goes up only 2/3s. 3. It DOES decrease, appropriately, down to empty; i.e., when filling tank, gauge goes up to 2/3s, as if obstructed. Mystery = how'd I screw it up by just having back opened? I can't recall, nor see, where I'd hit or otherwise damaged gauge. Thanks again. It's a privilege to enjoy your "vibe" & good wit, brains & heart. Have a hip holiday.

You present the best videos for the DIYer. Keeping explanations simple and coming up with cool ways to test components.

Just helped me fix my fuel sender problem. Thanks

Excellent video! Even 8 years later. I was going to just replace a fuel pump / sending unit *knowing* that it would be the idiot's approach - and one that would cost around $400 just for the unit. But after watching your clear explanation and sensible diagnosis, I don't have anything to lose by copying your technique. Thanks for making this video!

If I don't get the link or information to make this FIXD thing ee work with my Samsung Galaxy S5 cell phone iIl will have to return this thing. I need both. The FIXD and the phone to read the FIXD thingee. Help please. Thank you

Wow i have been to mechanics and dont bother testing to this extent. This is great workmanship

I have a question. if you unplug the gage and the level drops to empty, wouldn't that automatically rule out the guage and wires as the cause? I have a 95 Accord with the guage stuck at full, and am at work away from my multimeter.

Matt, you are much like myself. If I run across something that I can do as an aside in the course of a repair, I find it very satisfying to go back to the customer and say "oh, by the way, I fixed the problem you were having with your fuel gauge" just as you got the satisfaction of doing.

What ? Repair, not replace ? What kind of union mechanic are you ? Don't you know how it's done ? You're supposed to replace the gauge & sender(or preferably say you did,ha,ha!)and then charge an exorbitant amount to the customer(age doesn't matter,who cares they gotta pay!) But seriously it's good to see you do what you did, I wish you where close to my neighborhood !

Might have been more efficient to put 12 volts to the sending unit and then use the DVOM to sense voltage at the sensor wire during bench testing. This would have allowed you to see voltage go from one end to the other and to find a middle ground fairly quickly and accurately.

Thanks man... super helpful video!!! DOITS

There's no access panel on a 1956 Oldsmobile, so determining whether the sending unit or a wire connection is bad means dropping the tank. If I have to drop the tank, then you may rest assured I will have a new sending unit in hand. I can always sell it on eBay if a wire was loose or bad. There, see? Not an idiot.

Smart people always goofy but I do appreciate the video and hey you show channel business you want to live your life I'm just playing around anyway take on being goofy if I could be smarter but we're born we're born with but anyway thank you for the bed I've got the same problem and I need to find out what it is and hopefully you have helped me solve that problem thanks again

Hey Matt, had a question, great video by the way ,if i want to check and see if the gauge is good thru the wiring for the sending unit in my car, can i just use a jumper wire between the signal and the ground on the sending unit harness back at the tank? , i don't have a resistor anywhere and not sure how to go about buying one, im worthless when it comes to electronics, my gauge is stuck on empty, i have a 91 mustang and i already replaced the antislosh module or how ford calls it "voltage amplifier" in the instrument cluster , i replaced the sending unit in the tank like 4 years ago but of course that doesn't mean anything, it could be bad again,thank you for your time!!

Unit might have originally been installed incorrectly.. slightly off and it was stuck against the wall at full. They can get crunchy when tank is kept below half full ( below the resistor).

A molecular biologist moonlighting as an auto mechanic? Can you realign my molecules? They keep bumping into each other, and it's got me all steamed up.

I don't usually enjoy videos this much, good work, VERY GOOD work, you are very entertaining and much appreciated here.

I just did these same tests on a GM this weekend. I'm an electro-nerd (mostly),so I have lots of resistors to choose from. I thought that was a pretty nifty way to check the gauge/wiring too. Great minds,something,something. :)

i have a 2000 monte carlo thats doing the same thing stuck on full when driving the car always reads full i hope you're in florida because i need mine fixed

Jesus the total cost was $125 for fuel pump / sending unit. and $75 tow truck.

You sir, are funny. I'll go check with a multimeter. Thanks for sharing! I know now where to start.

Great video I'm about to test my honda's sending unit now. Well demonstrated, again great informative video.

Big Matt great skill, good video, good job, good learning. Thanks, G-d bless.

Ok, I have determined my problem to be the gauge and now need to know how to test and replace 3 resistors on the gauge to see if that fixes it. The gauge is very expensive to replace.

Im facing this problem right now, the gauge is stuck at 1/4. Im not sure how to access the sending unit so im taking it to the dealer to evaluate. I replaced the sending unit a few years ago so this time it might be the gauge but lets check the sending unit for dirt, corrosion, etc. and then do the manual test with the gauge before ripping the dashboard out.

So if you use a test light to test the signal coming out of your head unit it should be a very faint blinking signal and you should read approximately a half a tank or so with a test light hooked in with a low wattage bulb if it goes all the way to ground there's probably something wrong with the resistance in the head unit I seen it lots of times you can't just test these things by grounding the wire and looking for full and empty sometimes the signal coming out is incorrect also with oil pressure and temperature sensors also you can also easily just find the resistance of your tank sending unit and by a resistor of approximately 50 ohms and determine what that should read

By the way, I was indeed fooled by your introduction. I was going like "what???" "he is just going to change the sender unit without doing any diagnostic???" "I want to revoke his rocket scientist credentials!!" "I wonder if owning that FireChicken has caused his IQ to finally level off with other FireChicken high school dropouts" :-)

My car scarpio fuel guage is show full But diese isl in tank one fourth What problem face in sending unit

Hahaha I said but wait ....when you rolled away and said change the part lol 😅😅

It's slow I would assume to account for moving fuel in the tank so your gauge isn't jumping up and down as you drive

My problem is different. My gauge works but my low fuel light stopped working. My sending unit is together with my pump in the same assembly. The assembly is expensive. What should i do?

Good information. Subscribed.

Great video, can only add a small safety tip: no smoking whyle opening a fuel tank!

Great attitude, great work, and great video. Very informative. Thank you Matt

pretty sure my mechanic is not capable of this level of troubleshooting

Please I am using daewo Kalos as a Taxi but my fuel gauge is not working, please help me to make it work

Copying Monkey Bones: I don't usually enjoy videos this much, good work, VERY GOOD work, you are very entertaining and much appreciated here. Love the sarcasm. I wish I had a sarcastic GPS. "Where are you going stupid, I told you to turn right"

Hi, I hope this reaches you. I have a problem with my fuel gauge. And here's what I did. Changed the faulty sending unit. Tested the unit and the gauge, it worked properly, by imitating empty, half, and full tank. But once I place it back inside the tank, the reading becomes unreliable. One of the main reason. It does not move when feuling up, or when I tried to deplete all fuel. Didn't move. It's stuck on the quarter position. My car is a KIA Sportage 1997-98. Just trying to restore it, since it's just passed down to me.

Hey matt..another good vid man..smart diagnostics. Just curious, did you happen to price out a new unit just in case? Depending on price, I don't think it would have been unreasonable to suggest a new one at that point, since you had it out and knew your wiring was good. I have a suspicion you may see that problem again :) However, a new unit would most likely outlive both the owner and the car, guaranteeing no comeback lol

Hi, I disconnected my sending unit but the gas gauge is still on full. Do you know what that means?? Thnx

Hey guys do you know what he used to clean and lube it with? And how did he close it, so it wont get damaged when put back in?

no specific place where you put the voltmeter wire especially no experience in electrical thing

Fascinating

You really had me fooled by the intro! I could hardly believe my ears that you were about to change the sending unit right off the bat! And good job on helping the fellow out, I'm sure that was quite satisfying.

I had to get a new fuel pump for my 1997 SAAB and now the gauge is stuck on empty. My mechanic thought it would correct itself once I started driving the car and even driving it on the freeway and moving the fuel around, up and down. Well nothing has changed. The gauge is still on empty. Anything I can do that is basic and not expensive? Thanks

I have a 2003 Buick Rendezvous that is notorious for fuel gauge problems. Mine works, but I get the low fuel light on the first start up. Even with a full tank of gas! The light remains for a few minutes and then the needle slowly moves back to the correct amount of fuel in the tank. And then if I start it up again it goes back to normal. Not a big problem, but I'd rather go ahead and fix it. Any help is appreciated.

You seems like a nice guy. Really taking care of your customers. I have the same problem with my 1999 civic. And thanks for your video

I'm trying to get my gauge to read adjustments on the fuel level bob so I can double check the wires in the back of the car. The wiring diagrams I came across don't have the same color wires as I do. Is it possible to connect the fuel gauge directly to the fuel level sending unit or does it require some type of resistance (perhaps when it was together with the rest of the instrument cluster.

I presume percussion remedy was NOT tried on this before? A good whack might have unstuck that float although if it was stuck for 7 years, it would highly unlikely that it would have come down by BFH. I would have definitely tried it, along with a double dose of Techron. I am somewhat disappointed that you were not able to actually find the culprit though because by the time you had the sender unit in your hand it was no longer exhibiting the exact symptoms while it was in the car. It certainly was no longer stuck at full.

My gas gauge doesn't work properly and when I fuel up the pump to will click off like I have a full tank.It will continue to do this through out my pumping my gas. My gauge it stop at bout an 8th. And it will bounce around from a quarter to empty until I take care of it. I have a 2007 Sebring 4 cylinder if that matters. Also my dash lights don't work if that gives you more detail on what my problem is. Thanks to you guys I took out my starter for the first time. Now getting it back together

You're a good man for doing things like this for people, and I can only imagine his reaction when his car was returned. Always a good thing to have that kind of positive karma. Hey, if you're in the 5 boro's of NY, let me know. I'm having the same issue the fuel gauge not indicating the correct level. Shame too, because I purchased a 2005 Kia Sorrento last week as a surprise for my daughter to take back with her to Texas for collage. Unfortunately, I didn't noticed the gauge issue until the gas light came on and almost ran out of gas.So now the car has to stay here with me until I get it fixed, and then another thousand dollars to have it transported to Texas afterwards.

I have an 88' crx with the same exact issue. Two questions. How did you open the inside of the sending unit? How did you apply the electrical contact solution? Thank you much!!

hHOLY COW...Is nice to have all the time in the world for testing...I just swap that garbage and I am ready to roll! If is domestic or a rice rocket you know all the parts are junk and need replacement anyways! Replace the whole enchilada!!! But if the video is all about the teaching and keep the rust going lets keep the testing rolling on and on!!!

What might be the problem on my 2001 Honda Accord EX with no problem with the gas gauge but the empty gas light stayed on even on full tank?

What are as did you clean, the point of signal touches the ground?

03 trailblazer...fuel gauge reads empty all the time...i know these cars have cluster problems...so how can i verify the issue

Sister has a 2004 Toyota Camry xle v6 with stuck fuel gauge at full, will try this muchas gracias. God bless America

I had my fuel pump replaced about 2 yrs ago. After about 8 months into the pricey repair job the gas gauge reflected empty tank once I near or go under a half tank of gas. What could be possible points to look at? This is frustrating as I depend on 99 honda odyssey van to transport myself and son who is severely disabled and in a wheelchair. Help greatly appreciated, thank you

Very thorough and precise explanations! Keep it up!

i made an acess panel for my camaro, i had a fuel pressure problem and a gauge problem. i have gone through the BS of removing a tank from a 3rd/4th gen fbody too many times. made a door under the carpet. my fuel gauge problem was a disconnected ground and my fuel pump feeder line was leaking not allowing the car to hold pressure after key OFF. problem fixed.

Great video, great guy, but, two key things weren't shown: getting the sending unit out (and back in) and the cleaning you did that made all of the difference. I am not complaining for the sake of complaining. I have a gas gauge (or a sending unit) that doesn't work.

my 2000 jaquar s type was stuck on empty so I put some gas and now it seems to be stuck on full, but I only put 10 dollars worth of gas.... Do you know what might be the problem? thanks.

So, I unplugged the harness and my fuel gauge didn’t move at all, even after trying to start the car. What might be the problem? I have a 1989 Honda Prelude

Mine isn't stuck, but I go a 1/4 of a mile and use 1/8th and stays. Or i go up a hill and gas gauge stays. One day ran out. Filled up only took 8 gallons. My car can hold 15. Meant had 7 in it. What could it be. Any ideas

I just filled up and for the first time ever the gauge appears to be laying down to the right. About an inch past full. Not sure what to do

If I haven't seen this video I wouldn't be able to know how to test and do check my fuel sending unit properly, I do try and fix my own cars to save money and I do appreciate your help sir. I have this 1998 lexus gs300 that it has a lump on the gas tank due to their gas tank design and my gas won't hit full even though I have a full tank of gas. I hope this will work now since both sending units works properly thanks to your guidance. I really appreciate you sir and hope you're doing well and still wrenching till today 🙏🏼🙌🏼

Gas gauge stuck below empty when full will not move when full 465 John Deer Lawn Tractor ?

To help answer Raju problem. I had to change my boats sending unit. Same issue. OK out of the tank and empty in the tank. Believe it or not, but the float stopped floating!? replaced it and it works now.

You are a good man. I love you. May our father in heaven bless you