Fiero Store gas tank sending unit (Page 1/2)
damittron JUN 12, 02:56 PM
I purchased a gas tank sending unit from TFS. I went on a nice long ride this last weekend, and apparently, the thing is only working for the first half of a tank...it stops at half a tank and it is up to me to decide how much gas I have from there. I know, the gas gauges on these cars is notorious for being off a bit, but this is a NEW sending unit (and fuel pump, injectors, fuel rail, etc.!!) and I would expect it to be at least acurate to, say, 1/8th of a tank.

Am I living in an alternate universe, or am I right?

Also - Is there a way for me to test this thing without dropping the tank, or do some trouble shooting before I drop the tank to make sure it isn't something else that is causing this? TFS replied to my email inquiry, and basically said, I could pull it out, send it to them, let them bench test it, then, if it's bad, they would send me a new one. That puts me out of commission for quite a while if history is any indicator as to how fast they can get me the new one, as well as having to drop the tank without any trouble shooting.

TIA for any help!

D.
Charlie1963 JUN 12, 04:24 PM

quote
Originally posted by damittron:

I purchased a gas tank sending unit from TFS. I went on a nice long ride this last weekend, and apparently, the thing is only working for the first half of a tank...it stops at half a tank and it is up to me to decide how much gas I have from there. I know, the gas gauges on these cars is notorious for being off a bit, but this is a NEW sending unit (and fuel pump, injectors, fuel rail, etc.!!) and I would expect it to be at least acurate to, say, 1/8th of a tank.

Am I living in an alternate universe, or am I right?

Also - Is there a way for me to test this thing without dropping the tank, or do some trouble shooting before I drop the tank to make sure it isn't something else that is causing this? TFS replied to my email inquiry, and basically said, I could pull it out, send it to them, let them bench test it, then, if it's bad, they would send me a new one. That puts me out of commission for quite a while if history is any indicator as to how fast they can get me the new one, as well as having to drop the tank without any trouble shooting.

TIA for any help!

D.



I just installed a new TFS sending unit about a month ago. Did you happen to notice the piece of paper that came with the new sending unit that said the float on the new sending unit might hit the baffle in the tank and may require some adjustment by bending the bracket to prevent it?

I compared the old sending unit to the new one and noticed that the new float has a wider arc that it swings on. I tied a piece of fishing line to the float arm then put the sending unit in the tank but didn't install the o-ring or retainer. Upon pulling on the fishing line I could tell the float was hitting the baffle.

Here's a good post with a cutaway of the tank showing the baffle.

http://www.fiero.nl/forum/A...060811-2-070182.html
damittron JUN 12, 05:42 PM

quote
Originally posted by Charlie1963:


I just installed a new TFS sending unit about a month ago. Did you happen to notice the piece of paper that came with the new sending unit that said the float on the new sending unit might hit the baffle in the tank and may require some adjustment by bending the bracket to prevent it?

I compared the old sending unit to the new one and noticed that the new float has a wider arc that it swings on. I tied a piece of fishing line to the float arm then put the sending unit in the tank but didn't install the o-ring or retainer. Upon pulling on the fishing line I could tell the float was hitting the baffle.

Here's a good post with a cutaway of the tank showing the baffle.

http://www.fiero.nl/forum/A...060811-2-070182.html




There was no such piece of paper in mine. I got it back in October of last year and didn't get to actually drive the car until April or so of this year, due to work it needed. The only thing paper wise that was in there, was a note telling how to re-wire it for the 2M4.

I guess I know what I have to do now though, sounds like a f*cking fuel tank drop is in my future. I am a stickler for following directions BTW, so I am very certain that there wasn't any paper saying I needed to bend the arm on the float, I would have seen it, and followed their advice.

D.
viperine JUN 12, 07:20 PM
Did the gauge work perfectly prior to the sending unit swap?
It's possible that the gauge needle is hanging up on the face of the gauge. I used an old flashlight battery to trick mine and see how the gauge responded to find this issue.

If the gauge moved correctly prior to the sending unit swap, it's not so likely.
damittron JUN 13, 08:55 AM

quote
Originally posted by viperine:

Did the gauge work perfectly prior to the sending unit swap?
It's possible that the gauge needle is hanging up on the face of the gauge. I used an old flashlight battery to trick mine and see how the gauge responded to find this issue.

If the gauge moved correctly prior to the sending unit swap, it's not so likely.



The gauge didn't work before the swap, due to the sending unit being bad. It did work shortly after the swap, when the tank was empty, it showed empty, then when I was working on it, I only put about 1/4 tank in it in order to keep from having to dump a bunch of gas if I needed to drop the tank again. Once I filled it up completely, it stopped working, so the float getting hung on something makes sense...well, in the absolute logical sense it does, but not from a "why the hell don't you fix that before you send them to customers" sense.
IMSA GT JUN 13, 09:36 AM

quote
Originally posted by damittron:


... "why the hell don't you fix that before you send them to customers" sense.



That's why I will NEVER buy anything from them again. Absolutely ZERO quality control. They let the customer work out all the bugs on most of their items. I find other sources such as Rock Auto or other parts stores especially for engine parts.
fierofool JUN 13, 09:56 AM
Take note of where the gauge was reading when you ran out of fuel. Reset the trip odometer and fill the tank. Then drive until you're just shy of the reading where you ran out of fuel. You should easily make 125-130 miles, even on a V6.

Does your gauge sit directly on E with the ignition off?

damittron JUN 13, 01:51 PM

quote
Originally posted by IMSA GT:


That's why I will NEVER buy anything from them again. Absolutely ZERO quality control. They let the customer work out all the bugs on most of their items. I find other sources such as Rock Auto or other parts stores especially for engine parts.



I am riding shotgun with you on that! Everything I have bought there, including a car cover that was supposed to be "Custom" made for my car has been a complete sh*t show. I initially was going to rebuild the old sender, but ran out of time, so paid $150 for one of theirs...bad idea. I take that back, I ordered the headlight rebuild kits, and they have been ok so far.
damittron JUN 13, 01:56 PM

quote
Originally posted by fierofool:

Take note of where the gauge was reading when you ran out of fuel. Reset the trip odometer and fill the tank. Then drive until you're just shy of the reading where you ran out of fuel. You should easily make 125-130 miles, even on a V6.

Does your gauge sit directly on E with the ignition off?



Yep...it was showing half a tank, nearly perfectly at the half tank line...and I ran out of gas. My refill was (87 GT) 10.7 gallons. That was 4.7 in a gas can, and 6 at the gas pump. Granted, I didn't top off hard, just let it stop twice, which may have put me a hair below full according to lore. Oh, and it was at 185 miles, plus some tenths.

[This message has been edited by damittron (edited 06-13-2019).]

FieroStore JUN 13, 03:14 PM
I am very sorry you are having trouble with the unit. It does carry a 1 year warranty and we are happy to replace it, if it is defective. The problem you describe sounds more baffle related though (thanks for the cutaway link Charlie1963). The Fiero uses a plastic baffle inside that is simply pressed over the filler tube. Over time, the press fit can loosen and allow the baffle to shift one way or another and sometimes it completely dislodges from the filler tube. This movement means that the baffle can interfere with the float on the sending unit. There definitely should have been a small piece of paper with a diagram and instructions about this problem in the packaging, taped to the box and/or stapled to the invoice.


quote
Originally posted by IMSA GT:
That's why I will NEVER buy anything from them again. Absolutely ZERO quality control. They let the customer work out all the bugs on most of their items. I find other sources such as Rock Auto or other parts stores especially for engine parts.


Unfortunately, we cannot “quality control” every customer’s 30+ year old gas tank (great help though IMSA GT…as always). We build a quality stainless steel sending unit at a reasonable price for a very small market. To think that RockAuto has better quality control than us is laughable. Great company to buy from at times but zero invested back into your car and little to no knowledge of your car. We understand that RockAuto's low prices are tempting, but the sad fact is that RockAuto hurts the Fiero market more than it helps.