Gas Tank Sensor Broke (by dealer)

My 2002 Pontiac Montana had a cracked gas tank leak that GM was repairing at their cost. I took it to the dealer with half tank of gas in it. The dealer replaced the gas tank at GM cost as it qualified under the defect. My wife picked the the van. and it read almost empty. She went to fill it up and it only took $33 usually its abut $55 to fill it from empty and she thought it strange. She drove 40 miles to church and back (she has driven that hundreds of times) and the gas needle was showing almost half again. She went to fill it up and coudl not put much in it. I took it back to dealer and said you broke the gas tank sensor. They said no we didnt. We just removed the tank and put it back. Its now going to cost another $700 plus to remove the tank again and about $160 for the new sensor. How do I get this dealer to make good on his breaking the sensor. If we had a bad sensor needle I certainly would have asked them to replace it when the tank was replaced. My wife retold picking it up almost empty. The dealer said no we put back all the gas when we exchange the tank so you got a half tank back. Well it registered near empty so it was broke when he installed it.



I need help how to get this dealer to make this good.

The dealer may not be at fault here. With near a full tank of gas and a gauge reading of halfway this means there is too much resistance in the tank sending unit or possibly a gas tank wire connector. This can occur because the simple act of transferring the pump module over can cause these things to go stupid. The simple act of unplugging and then reconnecting the wire connector to the pump module may cause a high resistance which will then lead to the gauge reading lower.

GM is covering the cost of a fuel tank (?) but this does not mean they’re covering any associated problems elsewhere.
Your vehicle is going on 7 years old with an unspecified number of miles. If the mileage is in the 100k category then the pump module should be replaced at the same time as the fuel tank. The pump module should be paid for by you with no labor involved since the tank is out and parts are being transferred anyway.

Basically you have a well worn part here that should have been replaced at the same time and the dealer did not “break” anything. JMHO.

I guess I was not clear enough. There was no problem with the fuel sensor prior to taking it in to the dealer. None absolutely none. We took the car into the dealer with half a tank not a full tank. The car only has 65K miles on it. GM sent a letter out to insure my car did not have the manufacturer’s defect in the gas tank. They should pay for it as the car was well under the mileage cut off. Dah there was nothing wrong with the part. I have driven over 10 cars well over 100K miles and none had a fuel tank sensor problem. Actually you sound like you work at a dealer. A well worn part. You jump to the conclusion on the mileage. The dealer didnot recommend chaning out the part. I would think they would jump to do more repair. Look it worked fine, they worked on that area and removed the part. We pick it up and it doesnt work. I believe in coincidence but come on you’d go for a thousand bucks I sincerely doubt it. I rather have the fuel leak and put up with the gas fumes then have a gas sensor that is now broke.

Where did I jump to a conclusion on mileage? I plainly stated that “IF the mileage is in the 100k…”. The key word there is IF.
The part in question, along with the wire connector that attaches to it, is well used by the sheer fact it is going on 7 years old. The fact you’ve never had a problem with another tank sender on your other cars is irrelevant to this case.

Get mad at me if you want. I’m not taking sides here; only pointing out to you what more than likely has happened. Wire connectors age and with any scale or corrosion the resistance in that circuit may go up. When the resistance in that circuit goes up the needle on the gauge goes down. It’s also possible that the float arm on the module could have been bent when they were transferring the module over to the new tank. Maybe the wire connector is only half plugged in; I have no way of knowing any of this. It is possible that they could have done something wrong; it is also quite possible they did not.

Obviously GM is not going to pay for the new pump module and it could be debateable as to whether the pump should be replaced at the same time or whether you would pay for this part of it.
Considering the age of the vehicle, and especially so if the fuel filter has never been changed, I think the pump module should have been replaced while the tank was out. JMHO anyway.

And OK4450, you’ve only been mechanic-ing for what, 30 years or so?

And to the OP: I would listen to OK4450’s advice. He’s almost always right. Actually… I don’t remember a time when he’s been wrong.

“I rather have the fuel leak and put up with the gas fumes then have a gas sensor that is now broke”

You would rather have a significant safety hazard in your vehicle than pay for a repair to eliminate that hazard? Well, at least we now have a better understanding of your reasoning process.

Your 2002 car is out of warranty by time if not miles. While it is possible that the dealer did cause a problem, it is not very likely. If the gauge did not work at all, then that would have likely been the dealer. However since it is showing classic age failure it is very unlikely the dealer’s error.

Now the fumes is a different matter totally. I can’t suggest what that is coming from or if the dealer was connected with that problem, but it certainly should be addressed NOW. It could be dangerous.

Repair of the fumes issue if repaired by the dealer may be taken care of by the dealer if they find it was related to their prior work or not. No way of knowing ahead of time, but I am guessing it was not. It would be more likely that it was brought on by the service but it happened because it was about to start anyway.

I know how you feel. $700 is a lot of money. But there is an alternative. If you take it to an independent mechanic, you are likely to find they do the job as well as the dealer but at a lower price. Dealers are not better or worse than independent mechanics, but they are almost always cheaper.

As for OK, he has proven to be very knowledgeable and accurate as well as courteous. His wording was careful and correct. I believe you owe him an apology. Like the rest of us, he is not being paid in any way for all the great help and education he provides. You may not have intended to come off sounding less than appreciative (it is easy to do when faced with a the situation you are facing) but remember OK is only the messenger.

FWIW OK, you’ve got my vote of confidence too.

The positive comments about me are embarassing actually. I don’t think I’m correct all of the time and think I could be more courteous than I am.
Anyhoo, if the OP is still following this I’m not saying the dealer is not at fault; only that you have an unknown situation and no one knows.

If the float arm was bent while changing the pump module over then yes, this is the tech’s fault.
If the wire connector is only half plugged in then that is also the tech’s fault.

If the module has gone stupid then this is no one’s fault; just the roll of the dice on a used part.
If the wire connector is aged and corroded this is not the fault of the dealer either.
GM has had some fuel pump connector issues. I don’t think the OP’s vehicle is one of those on the list, but many times those lists may be incomplete and other models should be on there.

The problem should be fairly easy to verify with an ohmmeter and by doing some probing of the tank wiring. If the tank is full and the ohmmeter shows high resistance through the tank connector then the module is more than likely bad and it’s just one of those things that happen.

Ok, so you’re wrong some of the time and you SHOULD be embareassed. Heh heh heh

Gents, I certainly appreciate yur comments. I really do. OK4450’s second time around was certainly more what I was looking for and for that I do appreciate the insight and potential problem areas or failure points.
Each of yu missed the asic facts though to wit:

  • fuel gage/sensor worked upon taking car to dealer
  • car had half tank of gas when left at dealer
  • car mileage is 65K not old by any stnd
  • dealer replaced defective gas tank which the sensor was attached and he had to handle
  • fuel gage/sensor did not work immediately upon leaving dealer 4 hours later (what part of these 4 hours represent an old warn out part.

Most of what has been said in all these emails have nothing to do with the facts except OK4450’s second post which indeed identify several points where it cud be mechanic error.

The smart remark remark about where I am coming from is the kind of retort found on such chat rooms.

I will close with just 2 comments: An excellent mechanic told me that it is very unlikely that the sensor failed while the car was off sitting on the dear lot waiting to be worked on. Its possible but the coincidence if very very unlikely. He went on to say a good dealer knowing even that if was coincidence would make good the sensor knowing that it was a rare situation and should incur that cost in the interest of keeping a happy customer

Just to let all of you know, I had meeting with the service manager today. He agreed completely with my viewpoint and will make good the replacement. He agreed just as OK4450 pointed out in the second post that handling a used part such as that it is quite easy for a problem to happen and the mechanic not be away of it.

Gentlemen, everyone is fallable. Mechanics sadly are human too. Those of yu that like coincidence and chance perhaps may try the lottery. Angrey, a post wud not make me angrey. I just thought the inital response was all one-sided and this forum was set up to provide information.

I think the line “yu have a well worn part and the dealer didnot break anything” sums up yur original intent. There was no information in the first post of potential problem areas. And 65K miles is about 3.5 years with most cars today as the avg miles driven is over 20K a year.

I am not going to return to this post again. I do appreciate all the sincere comments. I am not so sure I owe anyone an apology here. I made one inference in my 2d post that perhaps OK4450 worked/had workded for a dealer. I still wonder about that speculation. I thank all of yu gentlemen for yur effort in this post.

I had the same thing when a tank was replaced. Just the banging on the ring to get the pick up tube off was enough to wreck the electronics. The part was $500 so I waited until I need a pump too then replaced the whole thing. It is a risk you take when having work done and no one will guarantee that there will not be additional problems when fixing one problem. Its on your nickel IMHO. Everybody wants someone else to pay for their problems.

Another thing about GM fuel gauge sensors. I have run into this several times. Drop tank, remove retaining ring, carefully remove float assembly, check the two little wires that connect onto the gauge assembly, and VOILA! Previous mechanic had reversed the (typically) gray and black wires. Challenge overcome. Other issues noted above also could be at fault. Bent float or the float is hanging up on something not allowing it to travel all the way up. Replacement of fuel pump and strainer in Nov.'06 was about $120 for just the parts. Just make sure that the wiring is correct. Parts bought thru Car Quest. Have a known, good independent mechanic do the work.