Hey,

I've been having lots of trouble getting my car to run properly lately and I suspect the fuel pump is not keeping up anymore. I have a new fuel filter installed and recently upgraded to 30lb/hr and LE2 setup.

Anyone heard of/experienced a pump slowly pumping less fuel, dieing slowly in a way? My symptoms are rough unstable idle, surges/misfires, reduced performance, no codes, under normal tune oxygen sensors show more and more lean every hundred miles, retuned to lower injector rating to make the car run better (26lb/hr). I've triple-checked wires (new OTVC), plugs (very clean, white) and have new injectors.

Any thoughts?

Thanks,
Felix.

 

Yes my pump did not go out completely. I would check the fuel pressure and see what you have. My car ran horrible when my pump went out; I could not get the car to rev over 3500rpms going down the road.

 

Here's the question put another way:

If a car runs like CRAP with the tune it used to pull like a bat from hell with, and then I lower the injector rating value and it runs MUCH better, what is that? Is it not something in the fuel system, most probably the heart of it?

 

Yup, throw a gauge on the shader valve and see where it's at.

 

I'll tell you what happen to my LT1. I have got full boltons on my car, and every once in a while at WOT up top, it would miss very badly and the SES light would come on. Well, it got to the point where it would happen more and more. I could slowly run my car up to redline, no problem. I could drive spirted, but not go above 80% throttle or so with no problem. But WOT of any kind, and it would go slower rather than faster. Instead of blindly replacing the opti like most people do, or just throwing money at it, i threw a fuel pressure gauge on it, and at idle, etc specs were fine. However, when I revved it up, the fuel pressure spiked to almost 0. Replaced the pump/screen after trying the filter, and all was well.

Word to the wise, replace your fuel filter on all you rcars on a normal basis. A clogged fuel filter will burn a fuel pump up. I see tons of people replace a pump, to keep having problems every few months with a fuel pump going out. Turns out the dumbass never replaced the filter, and the pump was having to pump at max capacity at all times to get enough fuel to the engine, burning it self up in a short amout of time.

 

Thanks for the info. Fortunately I've changed my fuel filter every year or so, and right now it's 500miles old. The pump I'm sure is original, 60k mi, 14 years old