Got my riv back in the driveway. Fixing fuel gauge woe

Fuck Rock Auto, I stopped buying from them because of their shipping cost's!!!!!!!
Correction: The only thing worth buying from Rock Auto is the subscription to Infotraxx. This is an electronic subscription to Technical Service Bulletins for any vehicle for one year. Does not require shipping as they just email you a password and you go directly to Infotraxx's website and login. I've been printing out about a dozen a week and started a binder for reference, should have all TSB's for my vehicle within 6 mo's, then I'll start downloading for my other car. Unfortunatly you can't download to disk and there is no printable index. You have to print each one out at a time and create your own index. But, for $12.95 for 0ne year's access I thought it was a good deal.

Hey Manofmany - if you don't need that ebay sending unit now, I might be interested in buying it from you. If it's the right part number, I need to buy one anyway...

SToP I didn't end up buying it. It probably would have worked though. is the 8th digit in your vin a 1? What year? It should work and $27.50 shipped isn't bad.

I was going to until I accidently broke the return fuel line. The plastic was brittle. 183k miles will do that

No sweat - I just figured if you bought it already, you wouldn't need it after the mishap with the plastic line. Figured I'd help you recoup your cost. I have the same year/engine as you. . I should get a sig soon!

I'm game to try it, I can't see what difference it would make but I'll maybe try to do some research on alldata at the library before I order.

Let us know how it goes when you get your parts this weekend!

I'll be sure to report back, possibly with pictures if I can remember to charge my batteries.

I REALLY REALLY hope I can find someone who sells that locking ring locally or somewhat locally. Maybe i'll get with eric and see if he can help source one.

The part numbers are different: '97: 25314202 '98-'99: 25177749

The '97 should read 40-250 ohms between PPL ckt 30 (gnd) and BLK 452
'98-'99 should read 40-248 ohms between PPL ckt 30 and BLK/WHT 651 (gnd)

Fuel level is interpreted by the PCM in '97 and ckt 455 goes to the gauge.
Fuel level is interpreted by the IPC directly in '99

I still think this can be used - maybe not a direct plug and play but it should be usable. The '97 unit is $112 on rockauto, the ebay unit is $25. For the price, I'm game to try it so I ordered the part just now. I'll let you guys know if it works once I get it.

BTW, rockauto shows the Delco part number for the '99 as 25335941 and 25314202 for the '97.

Good info.

I'll report back tomorrow with how things go.

Got the new Airtex pump in. The locking ring was tricky since I marred the original tabs up quite a bit getting the old ring off because it was so rusted. Got it running great

Gonna take it on a trip to Avon later and run the gas out to see if my gauge is working properly. Thanks for all the help guys,

I would also like to add that this fixed another issue.

Sometimes when I would turn the key over I would get nothing. Happened randomly time to time. Sometimes it could take 10 turns of the key to crank.

Must have been a short back there in the pump I guess? Hasnt done it once since I changed it.

A bit of info for the next guy who has this "classic" gauge problem...

(I wondered why the car lot that sold me the car was so eager to send me off with a full tank!)

While I know there are times that you should replace something "while you've got it apart" (my family ran a garage for 55 years), IMO this isn't one of them. The access is easy compared to the traditional drop-the-tank method, and the difference in price is just too high.

When you can find them, $50 isn't too bad for the sending unit alone (4 years ago I couldn't find one.) However, changing out a quiet, full-pressure pump for $300+ is unnecessary and a giant ripoff! Besides, the supercharged models have a higher capacity pump with a discrete speed control module that runs it at partial power until full output is needed - I should think that makes it last longer in normal driving...


There is, however, a quick & dirty & free solution:

I can't remember for sure what this locking ring is made of, but I should mention that I was originally trained not to bang on those rings with anything ferrous, 'cuz one spark can ruin your whole day... Even when prying with a steel tool you should probably wrap some duct tape around it. The easiest way I've always found is to use a hammer and a brass drift to tap at each of the ears on the locking ring sequentially until it loosens and rotates.

Anyway, back to that damned sending unit. I couldn't believe that the hulking bronze bushing they used wasn't holding things together tightly, but that is the problem. It has to be a design/manufacturing flaw, because that bushing is so tough that after I removed the sender from the pump assembly, I couldn't even use a vise & a hammer to squish it down and remove the play between the brushes and the resistor board.

I finally realized that I could unsnap the resistor board from the rest of the sender unit, and that would give me juuuuuust enough clearance to bend the brushes toward the board location.

...I put everything back together and it has worked perfectly for nearly 4 years, for $0.00.


PS - These "20 gallon" tanks only hold about 17.5 gallons...

Eldo wrote:

PS - These "20 gallon" tanks only hold about 17.5 gallons...

depends on what year riv you have. i believe the 97+ are 17.5gal. the 95 and 96's are 19.6 gal.

you didnt happen to take some pics of this free fix did you?

oh, and welcome to the forum. great first post!

[quote="Mr.Riviera"]

Eldo wrote:

you didnt happen to take some pics of this free fix did you?

oh, and welcome to the forum. great first post!

- Sorry. As I said, this was almost 4 years ago, and I didn't have a digital camera yet...

- Thanks for the compliment. I'll try to refresh my memory and post some other electrical mods I made way back then. I didn't like many of the ways that GM designed things (like the express-down window), so like Tim Taylor, "I rewired it..." (Minus the Emergency Room)