Why did I stall???

[1993atx]

Ok, heres the scenario...The car began the day running great-and it has been running fine for the last few mos.. Today I notice a whining/buzzing noise coming from the area of the gas tank when the car is idling. The noise is somewhat like the noise of the power seat bolsters filling with air, and also there is a higher pitched whine accompanying the buzzing noise. This didn't bother me b/c I had never noticed it before and figured it was just the sound of the fuel pump SO...I shut the car off for a half hour, and when I start it again the engine idles a little lumpy at about 800rpm. I pull out into traffic, and the car goes about 100 yds. and loses power quickly and stalls I try to start it and it turns over but won't start. After a few minutes, the car starts and drives normally-no CEL, no anything! After doing a search, I found it hard to narrow this down b/t IAC, CPS, fuel pump/filter etc...
I'll check the codes tomorrow, but with no CEL I'm wondering if I'll get any.
Will the fuel pump make the computer throw a code? The car has only 66k if that helps. Thanks for any help.

 

[wood_e]

I say your fuel pump is probably going bad. They'll work, then not, then work again. Check your fuel pressure.

 

[1993atx]

Should the car be running to check fuel pressure? I understand that I'm looking for 35-40psi, but does the car need to run for awhile to build pressure. I also wonder-the temperature has risen 20-30 degrees here this past week. Would that help to exploit weakness in the pump?

 

[wood_e]

I would think the hotter weather may effect it. You're looking for 33 PSI when the pump is primed at the rail, and 35 running and 42 I believe with the FPR vaccuum line removed. You may want to do a search for exact numbers but IIRC those are close.

 

[SHOtimer]

Your fuel return line check valve and fuel pump both should be replaced. The check valve can become a more apparent problem as the weather warms, and the pump is probably just tired and worn out.

Doug

 

[93_blk_blk_mtx]

Autozone has a lifetime on their fuel pumps for about $80.

 

[1993atx]

The day after...
This morning was very cool and the fuel pump seemed to be quieter. No problems yet-so I ran the codes hoping for all to be revealed.

Here they are:

KOEO: 511-No power to PCM pin 1 or bad PCM(processor)

KOER: 225-Knock sensor not tested(ignore if not pinging)

511-probably due to my lpm

225-the car may ping a little, but I don't think that's the issue.

Without disconnecting anything I am getting 32psi at the fuel rail during idle, and jumps to 38-40psi when the throttle is blipped-normal right?.

Do I just have to wait to be stranded, or is there something else I can check?