gormant1

OK guys, I would like to get a lot of responses to this post so that we can get a good sample size of people's experiences.

So my luck with using non AC Delco parts on my 91 Formula has not been very good, especially when it comes to fuel pumps. I purchased my car in 2003 and since then I have put 4 fuel pumps in it. The first time it went out was in 2006. When I replaced it I bought a pump from Carquest (not for any specific reason other than I get a lot of my parts from them for my Alignment shop). After about three days the pump started giving me trouble. I could drive for about 20 minutes until the pump got warm and then it would shut down. I figured than I must have gotten a bad pump so I got them to warranty it out and got another one. About a week went by and the same troubles started arising again. Same story, got the pump warrantied and put it in for the third time. About another week went by and I started having the same trouble.

At this point I knew something else was going on. My dad called a friend that worked for the Chevrolet dealership and he asked us what type of fuel pumps we had been installing. So we told him we were getting them from Carquest. He told us that was our problem. He said that he wouldn't use anything other than AC Delco parts and told us to come down and pick up a Delco pump. We did so, installed the pump, and we have never had another minutes trouble.....until now. I am about to put another pump in and I plan on replacing the sending unit as well because the guage has been reading wrong for a while now.

So the question is, have any of you guys had any success using non AC Delco fuel pumps? How about non AC Delco sending units? What were your experiences? The AC Delco sending units run about $330. On the other hand the Spectra sending units cost about $130-$170. I really like the price on the Spectra unit, but its not worth it if its going to cause trouble down the line. I just figured that I would see what you guys have experienced with this issue before I make a decision.

I appreciate any input you guys can provide. Thanks, Thomas.

keykey

Are you sure it's not the fuel pump relay? How is your fuel pump pressure switch, ever replaced?

gormant1

The relay tested out fine. The fuse up by the battery (orange wire) tested out fine. I applied 12 volts directly to the (grey wire) fuel pump hot lead. The pump didn't turn on. Ground (black and white wire) tested fine, ECM signal (green and white wire) also tested fine.

I am not familiar with a fuel pump pressure switch. It did not show up in the wiring diagram for a 91 formula.

-=Z28=-

iTrader: (3)

My father and I have used AC Delco for years. They are a reputable company that has been around for a long time.

(HINT) Just cause they want 300 for an ac part at a part store, doesn't mean you cant find one for cheaper. I buy a lot of stuff from ebay for cheaper. Gotta do a little digging sometimes but usually I succeed.

As for other company's, I haven't heard of that one before. Maybe others have, so I cant comment on them. I do know that Id rather pay 50-100 more just to prevent from doing it again down the road due to a cheaper part. You said it yourself that you have changed it 4 times. So 4 x what you payed v.s 330 once for a delco part.

Maybe something else is wrong causing your pumps to fail so often???

-Dan

gormant1

Hey Dan. Thanks for responding. I have changed the pump 4 times. But I have never changed the sending unit. I will definitely be using an AC Delco fuel pump. It's the sending unit that I am on the fence about.

MoJoe

iTrader: (5)

I've heard ACDelco quality is not the same as it used to be...
FieroGroup
Racetronix sell Walbro pumps...L98 kit, which have had good reviews, and no bad reviews I've seen.

-=Z28=-

iTrader: (3)

MoJoe, That very well may be. It seems as time goes on that many American founded companies are doing just that. Cheaper to have it build in china. sad. I would research it out and find the best pump. I too have heard good things about Walbro pumps, however they have been around forever as well.

Im a jack of all trades, and years ago, the power tools Id buy would say made in USA or Switzerland. Now I cant find ones that dont say china on them.

Same with Jonsered chainsaws. Before Stihl, they were leaders. Made in Sweden. Now both Stihl and Jonsered have the china stamp on them. WTF America....

Im going to go do a smokie burnout for good ol America.

-Dan

(edit) WOW!! I cant believe all the forums/threads about china build junk AC delco parts. I just emailed the company asking why and if they know how bad its effecting their name. This truly saddens me cause I/Dad/even Grandpa used and would stand by their product.

RBob

iTrader: (1)

The AC Delco parts are now being made in China, they have gone from being the go-to part to 'avoid at all cost' parts. With the fuel pumps this started just a couple of years ago.

One recent pump that folks seem to be having good luck with are Bosch. Get a stock replacement TPI pump in the Bosch brand.

As for the AC Delco parts, if the box has Made in China on it, don't use it. Doesn't matter what part it is, it is junk. Example, brand new AC Delco A/C compressor. Lasted 1 year and 3 months (out of warranty) before it dumped the entire charge.

Case o-ring went out in the middle of Winter while the car was parked. There isn't more then 400 miles on that compressor.

RBob.

jpearcy1

iTrader: (1)

Those searching for Delco parts I recommend gmpartsdirect.com and delco's budget parts are china made while others are USA made. I forgot how to tell the difference though.

alex722607

iTrader: (3)

Or swap to a 4th generation plastic tank which has a better fuel pump all together.

Fast355

iTrader: (2)

I have had a 3 year old Delphi fuel pump in my Express for about a year now. Still working well, knock on wood. GM upgraded the connector and included a new pigtail to convert my harness to with the new pump. Fuel pressure is right at the factory specification for the marine regulator on my setup. The pump runs quiet and holds pressure. The original Delco pump ran 18 years, nearly 100K miles and was still working when I removed it (bad fuel level sending unit and low fuel pressure under load due to resistance in the connector).

I used all Delco/Delphi tune-up parts when I put headers on it back in November and the engine has never run better. Last Wednesday it start hesitating badly with load or throttle and barely made it home. Check engine light came on for a knock sensor. When the check enginge light came on, started running about 50% better. Was still showing active knock retard and in low octane spark maps. Unpluged the sensor, turned off the knock retard in the tune, disabled the diagnostic check for the sensor, and cleared the PCM memory so it would be in high octane mode. Power was instantly back. The aftermarket knock sensor I put on it at the same time after noticing the factory sensor had a broken connector is to blame. Bought a Delphi on Friday just have not had time to put it on. Drove it 500 miles round trip with 6 people without a working knock sensor and didn't miss a beat.

-=Z28=-

iTrader: (3)

Did some more digging and they (AC) claim that there are many company's out there making counter fit parts and using their name. Look out for AZ delco boxes, cheap cardboard/flimsy, or paint that is not deep and defined.

-Dan

86iroct5

for fuel pump i would not dable with anything that isnt ACDelco or similar WELL KNOWN performance upgrade like walbro (what im running, bolt in from summit) or aeromotive that is a job that i want to do once and only once.

BrianI

Thomas, I've installed 2 Spectra sending units. One in an 88 Iroc and one in an 88 GTA. The fuel gauge on both cars were not accurate afterwards. I'm not sure if the sending units are to blame because both cars were not running when I bought then so I don't know if they had fuel gauge issues before. If I had it to do over I would have bought AC Delco sending units. Fyi

gormant1

Thanks for that Brian. And yes, I did end up going with the AC Delco pump and sending unit. Hopefully it will all be completed by Sunday.

BrianI

Good deal. Let us know how it works out.

gormant1

Found something interesting when i got the tank and the sending unit out. The protective sleeve that goes around the fuel pump was completely dissolved and floating around in a thousand pieces. The parts that were not floating around in the tank we sucked up in the sock filter that is attached to the bottom of the pump. Has anyone ever seen this before. It make me wonder, if the protective sleeve is going to eventually dissolve anyway, whats the point on even putting it on the pump to begin with. It seem like your just asking for trouble. But this is another piece in the puzzle in terms of why my car would run like crap when it even ran at all. So far this is what I have found:

~5 bad injectors
~broken water temp sensor
~chewed up vacuum lines under the plenum
~broken wires on the IAC valve
~bad alternator
~dissolved fuel pump sleeve contaminated fuel and sock filter
~chewed up wires on the disctibutor connectors

It's amazing what 5 years of sitting will do to a car!

TylerSteez

iTrader: (3)

Sounds like you have a couple of furry friends in your garage that seem to like hanging out around the plenum lol

gormant1

It was actually out in the driveway. And yeah, squirrels.

gormant1

Update: So before I put the sending unit back in the tank I put the fuel pump on it and hooked it up to make sure it would work before I put it all back together. Turned the key on and the pump fired right up. SUCCESS! Right? Not so fast. Next I put the tank back in and hooked everything back up. Dropped the car onto the ground and turned the key. The car fired right up. Within a matter of seconds the intake was covered in fuel as it gushed out of the fuel rail. DAMN IT! So heres the deal, after I installed the new injector and fuel rail O-rings, I never got a chance to check it for leaks because the fuel pump went out as I was doing it. So now I will take it back home and pull the plenum back off to see where the leak is. I really hope its not the injectors. They are brank new Bosch IIIs from Southbay Fuel Injectors. On the bright side, I went ahead and put the new tires on it while I had it at my shop. So at least there's that.

BTW: Here are a couple pictures of the dissolved fuel pump sleeve floating in the tank and the fuel pump sock. Note how black the sleeve got from all of the debris it sucked up.

Bob88GTA

iTrader: (2)

Did you install the injectors into the Intake first? The following is direct from SouthBay:

"The complaints that we have received throughout the years with the bosch lll's is that fuel leaks from up top if the injectors are installed into the rail first and that's an installation or an o-ring issue. We have found that when they are installed into the intake first it alleviates all leakage from the rail side, has to do with alignment. The reason why the o-ring is square is that we have them custom made for our adapter and for proper fitment. When we first designed the adapter for the bottom of the injector we did R&D for about 6 months to make sure fitment was perfect before we started selling them. They are specific for the adapters and yes you are correct, they don't sit as far down into the intake as the stock, but it is ok. Guarantee you will not have a vacuum leak. Will tell you that the injectors will more than likely leak if they are not installed properly."
__________________

alex722607

iTrader: (3)

this

gormant1

I definitely put them into the intake first. I followed those instructions to the letter. I even lubricated the O-rings with dish soap, per the instructions. I'm not sure whether my leak is coming from the injectors or the fuel rail. If the weather cooperates this week I will pull the plenum after work one night this week.

southbay08

Did we send the injectors with the adapter on the bottom? Or do you have an aftermarket intake?

gormant1

Yes, you sent the injectors with the adapters on them. And my intake is stock. If it doesn't rain this evening I am going to pull the plenum and see exactly where it's leaking. More to come....

alex722607

iTrader: (3)

That's one thing I don't miss about TPI- pulling the plenum and then having to go and get new gaskets to put it together again.

You could have a leaking cold start injector. It happened to me so I deleted it.

gormant1

My car is a 91, so it doesn't have the cold start injector. And the plenum gaskets have only been on there for about a month, and the engine has only ran the one time, and only for about 30 seconds so not even long enough to get warm. Needless to say I will be reusing those gaskets.

Bob88GTA

iTrader: (2)

they(gaskets) will be fine. Did you have someone turn the key to ON and you watch where the fuel is coming from yet? There's only a few joints/connections it can leak from. The fuel line connections, the two fuel rail O Rings, and the injectors themselves.

gormant1

No I haven't done that yet. Last night after work I loaded it up on the trailer and took it back to my house. After unloading it I was too tired to go any further.

I believe there are 5 or six O-Rings on the fuel rail. Two up front, and I think three on the back by the regulator. I know because I replaced them all when I did the injectors. Hopefully tonight I will figure out which one the culprit is. The life of a car guy...

Bob88GTA

iTrader: (2)

"three on the back by the regulator"

Oops, forgot bout those!

southbay08

The only time an injector will leak from the rail side is from improper installation, bent oring, or the injector being too short or too long, which in your case they are not since we sent the injectors with the adapter and you have a stock set up.
Please keep us posted!


www.southbayfuelinectors.com
516-442-4707
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gormant1

Problem solved. So last night I pulled the plenum and turned the key to prime the system. I quickly discovered cylinders #4 and #6 were leaking where the injector goes into the rail. Loosened the rail up and pulled the injectors out to find that the O-Rings got pinched. A picture of the pinched ORing is attached. I guess when I assembled it the first time I didn't put enough dish soap on the ORings. So I took two ORings off of the old injectors and installed them onto the Bosch III injectors. Perfect fit and they really weren't that old. This time I completely doused the ORings with dish soap and also put some on my finger and put it into the holes in the fuel rail. Put everything back together and BAM, no leaks. Car is running great now. Thanks to everyone for the advice and help. Now I have to get the body of the car back into good shape. New day, new project....

southbay08

Yup...that'll do it. Well glad you got it straightened out!