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-   -   Cranks for 10+ seconds before firing after a new fuel pump install (https://www.gmforum.com/2000-2005-90/cranks-10-seconds-before-firing-after-new-fuel-pump-install-287615/)

t1475dt 01-19-2010 09:39 PM

Cranks for 10+ seconds before firing after a new fuel pump install
 
Hi guys, I'm new here but somehow I think you guys don't care and you just want to help, ha ha!! I've got an '01 SSEi that I bought last summer. She needed a lot of TLC but we're slowly getting things taken care of. The car was running really rough and stalling at lights and stop signs. I have a spare complete L67 which is good for swapping parts. It has a new FPR, and fuel filter. Still didn't fix it. I removed the sending unit and pump housing from the tank, and replaced the pump with a pump from a '02 Grand Prix(non s/c). Now the car runs like a raped ape!!! No stumbles or dying at lights. New problem now, it won't hold fuel pressure. If it sets for more than 5 minutes it cranks for over 10 seconds before starting. The FPR is still good, and I do NOT smell fuel anywhere. Is there a valve or anything else that I may have messed up while having the pump unit out of the car? Right now I just turn the key on for 2 secs off for 2 secs and then back on until the pump stops and it fires up after 2 seconds. This is probably a simple fix for y'all and I would greatly appreciate your wisdom! Thank you, Danny Just put 2 new rear wheel bearings on this past weekend, wow, who needs a Cadillac!!!!!

crunkfrunk 01-19-2010 09:42 PM

Maybe since you took a pump from a non-supercharged GP, I know the SSEi has a 2 speed pump so something with the pump controller could be causing the issue

Danthurs 01-19-2010 09:54 PM

Get a fuel pressure tester, turn the key to on, but don't start. What is the fuel pressure. Then start the engine, what is the fuel pressure.

Purplehazeir 01-19-2010 09:57 PM

The fuel is leaving the rails and draining back to the tank. That's why it's taking 5 seconds for your car to start...no fuel at the injectors.

It could be a combination of the pressure regulator and low pressure from the GP pump. The pressure regulator can't close, so when you shut down the car, the fuel drains back. I can't remember if there is a check valve on the right fuel pump or not...anyone?

I think the reason you're running as good as you say is that you are probably running very lean. Which can be damaging to your engine. The best bet...get the right fuel pump for the job!

t1475dt 01-19-2010 10:01 PM

Key on is 52 to 53 psi, Running it is 48 to 49 psi. sounds good to me. I have seen on other forums that the non s/c fuel pumps are good to around 300 HP. It should at least work for now until I can afford a good aftermarket pump. I remember the pump I installed had a small thin black rubber stopper of some sort on the bottom of the housing. Is this a one-way valve or something that could be bad? Thanks for the replies!! Danny

t1475dt 01-19-2010 10:05 PM

Purple, you're absolutely correct. I need the right pump!! I know, lean is mean, but wouldn't the pcm compensate for a lean condition? How much should I expect to pay for a good Walbro or similar pump for my application, and what pump do you fellas recommend? Thanks again.

sawgunner 01-19-2010 10:12 PM

around $300 from autozone or advanced

Danthurs 01-19-2010 10:15 PM


Originally Posted by t1475dt (Post 1421467)
Purple, you're absolutely correct. I need the right pump!! I know, lean is mean, but wouldn't the pcm compensate for a lean condition? How much should I expect to pay for a good Walbro or similar pump for my application, and what pump do you fellas recommend? Thanks again.


Check at www.rockauto.com The PCM can't compensate if the pump can't keep up.

Purplehazeir 01-19-2010 10:17 PM


Originally Posted by t1475dt (Post 1421467)
Purple, you're absolutely correct. I need the right pump!! I know, lean is mean, but wouldn't the pcm compensate for a lean condition? How much should I expect to pay for a good Walbro or similar pump for my application, and what pump do you fellas recommend? Thanks again.

The PCM isn't a miracle worker. It does have it's limits and it will compensate the best that it can as long as it has things to work with..like, air, fuel and spark.

Stock pumps vary in price from $250 up to $375 at Rock Auto.

Walbro has the pumps for $250.

Either a Walbro or a Delphi pump is the way to go.

crunkfrunk 01-20-2010 06:30 AM

Are you planning on doing mods that will require larger injectors and thus more fuel? IMO it would be a waste of money to put a Walbro in for just a stock application, if you want a used stock replacement for around $100 let me know I know some guys


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