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Fiero Store gas tank sending unit by damittron
Started on: 06-12-2019 02:56 PM
Replies: 17 (635 views)
Last post by: DrXtreme on 05-02-2021 06:07 PM
damittron
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Report this Post06-12-2019 02:56 PM Click Here to See the Profile for damittronSend a Private Message to damittronEdit/Delete MessageReply w/QuoteDirect Link to This Post
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.
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Charlie1963
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Report this Post06-12-2019 04:24 PM Click Here to See the Profile for Charlie1963Send a Private Message to Charlie1963Edit/Delete MessageReply w/QuoteDirect Link to This Post
 
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.

//www.fiero.nl/forum/A...060811-2-070182.html
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damittron
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Report this Post06-12-2019 05:42 PM Click Here to See the Profile for damittronSend a Private Message to damittronEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
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.

//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.
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viperine
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Report this Post06-12-2019 07:20 PM Click Here to See the Profile for viperineClick Here to Email viperineSend a Private Message to viperineEdit/Delete MessageReply w/QuoteDirect Link to This Post
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.
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damittron
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Report this Post06-13-2019 08:55 AM Click Here to See the Profile for damittronSend a Private Message to damittronEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
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.
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Report this Post06-13-2019 09:36 AM Click Here to See the Profile for IMSA GTClick Here to Email IMSA GTSend a Private Message to IMSA GTEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
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.
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Report this Post06-13-2019 09:56 AM Click Here to See the Profile for fierofoolClick Here to visit fierofool's HomePageClick Here to Email fierofoolSend a Private Message to fierofoolEdit/Delete MessageReply w/QuoteDirect Link to This Post
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?

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damittron
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Report this Post06-13-2019 01:51 PM Click Here to See the Profile for damittronSend a Private Message to damittronEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
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.
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damittron
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Report this Post06-13-2019 01:56 PM Click Here to See the Profile for damittronSend a Private Message to damittronEdit/Delete MessageReply w/QuoteDirect Link to This Post

damittron

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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).]

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FieroStore
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Report this Post06-13-2019 03:14 PM Click Here to See the Profile for FieroStoreClick Here to visit FieroStore's HomePageClick Here to Email FieroStoreSend a Private Message to FieroStoreEdit/Delete MessageReply w/QuoteDirect Link to This Post
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.
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damittron
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Report this Post06-13-2019 03:44 PM Click Here to See the Profile for damittronSend a Private Message to damittronEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by FieroStore:

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.

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.



Matt,

This is probably the reply I should have received (via email) first. I can appreciate that you don't know anything about my car, I don't expect you to, that would be completely unreasonable. My car has less than 2000 miles on it, I pulled the tank in December and inspected/cleaned it, checked everything out on the inside and there were no issues with the baffles. I did dry fit it before I locked things down and made sure everything fit properly, everything was good. I will pull the tank in the next couple of weeks and see what is going on.

I rebuild cars as a hobby, I currently have several and have been working on several makes for about 35 years, so this isn't my first rodeo.

If this were the first issue that I ran into with your parts, I would definitely not have been in agreement with IMSA GT, but it isn't my first issue. I am sure I will buy more parts from you guys, but I will likely be very cautious about what they are and how difficult they are to install.

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Report this Post06-14-2019 01:55 AM Click Here to See the Profile for donuteater306Click Here to Email donuteater306Send a Private Message to donuteater306Edit/Delete MessageReply w/QuoteDirect Link to This Post
Unfortunately my 2 year old sending unit has never worked properly either, so I use the trip odometer and refill at 220 miles. Two issues: 1- I'm sure the float it's bumping into the baffle, and 2- the gauge doesn't display the fuel level consistently.

My original sending unit and gauge were surprisingly accurate for a 30 year car with 250k miles. What happened is, I failed CA smog because of an evap leak. The leak was a cracked weld on a metal evap line on the sender. Rather than repair the line, I decided to replace the sender with a FS unit.

The new sender did come with the paper explaining the possibility of interference with the baffle...the shop that installed it said there were no issues. The 1st time I filled the tank, the gauge sat on empty until I hit a few bumps, then went to full. Clearly the shop did not test for interference...seems obvious (or most likely), the float is getting hung-up on a baffle. Shops fault, not the product.

Maybe it's related, but the gauge doesn't show the fuel level consistently...Within 20 miles of driving, the needle drops to 3/4 tank. Gauge sits at 3/4 until about 100 miles, then drops to 1/2 tank, nothing in between. Sometimes while driving, the gauge will drop to 1/2 tank at 50 miles, then goes back up a little, then drops to 1/2 again at 100 miles. By 150 miles, the gauge is resting on "E". Refilling at 220 miles takes roughly 9 gallons. I average between 25-27mpg with the 5spd. We have to support TFS. Our vehicles are a dying breed and GM gave up on us 30 years ago lol.

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Report this Post06-14-2019 09:14 AM Click Here to See the Profile for FieroStoreClick Here to visit FieroStore's HomePageClick Here to Email FieroStoreSend a Private Message to FieroStoreEdit/Delete MessageReply w/QuoteDirect Link to This Post
Scott:

Unfortunately, we don't know whether or not the part is defective. The symptoms you previously described suggest it's not, but until we have more information, we just don't know. If the part is defective, we will be happy to warranty the part for you. Defects are rare, but they do happen from time to time. We have sold nearly 1,000 of our current manufacturer's sending units and their defect rate is well below 1%.

I looked through your order history and did not see any other warranties or abnormal incidents on your account. We would like to learn more about the details that you alluded to.
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Report this Post06-25-2019 03:23 PM Click Here to See the Profile for Initial.FClick Here to Email Initial.FSend a Private Message to Initial.FEdit/Delete MessageReply w/QuoteDirect Link to This Post
I had issues with mine... but it well past warranty....bought it and it sat in the box for 1 1/2 years ” I finally installed it and the gas gauge stays on E” ...pulled it again and tested the gas gauge and it worked.....installed the gauge...and the gauge sat on E... Again!

Hooked a external gas gauge and it stayed on E....said screw it and drove the car with a non working gas gauge.....then the fuel pump stops working. Pulled the tank AGAIN! And saw the grey connector loose.... tested it and the wire had a short...then the grey connect” inside the tank.....started messing up “ causing me to ditch the grey connector” I ended up shrink wrapping and hard soldering the wires” straight to the prongs” on the sending unit.


I installed the tank and guess what? Gas gauge still stuck on E.... the sending units look nice...but they need a quality improvement.

[This message has been edited by Initial.F (edited 06-25-2019).]

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Chris Eddy
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Report this Post06-25-2019 08:34 PM Click Here to See the Profile for Chris EddyClick Here to Email Chris EddySend a Private Message to Chris EddyEdit/Delete MessageReply w/QuoteDirect Link to This Post
I think that you should add another level of test.. if the sender is defective, one would expect the ohms wire to be broken or shorted or some such. A simple ohm meter reading should tell you where the sender is physically on the wiper. That could tell us more useful stuff.
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Report this Post04-22-2021 03:54 PM Click Here to See the Profile for hobbywrenchSend a Private Message to hobbywrenchEdit/Delete MessageReply w/QuoteDirect Link to This Post
Had to chime in ...My 85 GT bought new . In less than 8K miles from new the pump failed. I replaced it myself and now I am sorting out a 10 PSI rail reading.

Anyway, I now relate the main problem I have with Rock Auto. Paying online is a gigantic PIA. After decades of business I have emailed them numerous times and they have always answered that it is my card provider. With any other vendor check out is effortless. I have had a few bad parts always remedied IF WITHIN THEIR GRACE PERIOD. But when I lay in bad parts and age them I end up eating them. Long range planning is dangerous.

My original gas gauge has left me stranded a few times. I never have completely overcome the false 1/8 tank reading when it is really empty.
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Report this Post04-22-2021 06:00 PM Click Here to See the Profile for Dennis LaGruaClick Here to Email Dennis LaGruaSend a Private Message to Dennis LaGruaEdit/Delete MessageReply w/QuoteDirect Link to This Post
If you compare the Fiero Store gas tank sending unit to the OEM unit the design of the float and arm is different. For whatever reason the floats on those FS units interfere with the baffle. There was a member here that had to redesign the float arm and ended up locating the float in the middle of the arm by cutting it and making a T . The float was cut in half and each half put on each end of the T. You can find the post on this forum as it was only a few weeks old.
I've never had a problem with Fiero Store products but this one seems the exception. I believe the arm needs to be redesigned to mirror the OEM unit so that it will clear the baffle.

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Report this Post05-02-2021 06:07 PM Click Here to See the Profile for DrXtremeClick Here to Email DrXtremeSend a Private Message to DrXtremeEdit/Delete MessageReply w/QuoteDirect Link to This Post
I had the same issue on my 1988. Fix was bend the flat piece holding the sensing unit to bring float back to center. i posted pics of what i did about 6 months ago. its a real easy fix, but you do haveto drop the tank.

Dr Xtremw
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