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-   -   When a fuel pump dies---does anyone hear it? (https://www.nopistons.com/2nd-generation-specific-17/when-fuel-pump-dies-does-anyone-hear-73100/)

Mr. MagOO 09-08-2009 05:40 AM

Gentlemen, In the last 20 years I have owned my 1986 base model I have been able to pretty much diagnose and fix any problems myself. However I have run upon a problem that I can not identify although it appears to be fuel related.

Please bear with be because I think all these symptoms are related. On a 120 mile trip starting with 3/4 tank of fuel all went well untill I was returning and the guage reached 1/4. At that time I realized the car was surging/missing while in cruise. I took it off cruise and the missing became severe enough for the car to slowly lose speed from 80 to a point around 50 where I could maintain. I was on an interstate with few exits but I was looking for the first fuel stop. Thinking the guage was off and I was running out, I fish tailed the car and the miss/sputter became so bad the engine would shut off for a "one" count and then resume. Finally I made it to a station and upon removing the gas cap, a loud SHHHHSHING noise came from the tank. I couldn't tell if it was pressure or suction. I filled the tank, 10 gal, and the car ran fine all the way home.

Now, when I make a hard left turn, really swing the rear around, the car will die for a one count and then resume. An equal turn to the right produces no problems.

It appears my guage IS inaccurate but of course that will only leave me stranded one day.

Additionaly, I had fixed the dreaded 3800 rpm stall by grounding the CPU. Now however the car will miss and buck over 3800, not a surge but irratic misses all the way to redline.

I can hear the pump run by the way. Any ideas?

Rob x-7 09-08-2009 05:46 PM

maybe check or change your fuel filter, and you may want to check the sock at the bottom of the fuel pump to see if its clogged

Mr. MagOO 09-09-2009 05:56 AM


Originally Posted by Rob x-7 (Post 833757)
maybe check or change your fuel filter, and you may want to check the sock at the bottom of the fuel pump to see if its clogged



I appreciate the reply. This weekend the filter gets changed and the pump pulled. Are there any tricks I should know before I do the pump? I have never had it out before.

Also, is it normal for the tank to build pressure like it does. I took the cap off yesterday and the tank released a lot of pressure again. Thanks Mr. MagOO

j9fd3s 09-09-2009 12:25 PM

couple things to check.



most important is the filter on the end of the fuel pump, when these get dirty, they do weird things like cut out when cornering



the other pressure thing, is normal to a point. if the car runs great with a full tank, and gets worse as the fuel level drops, its a clogged charcoal cannister. also easy to check, its under the hood, the small line going to it, is the tank vent, so unplug it and see what it does

Aspect28 09-24-2009 09:23 PM

I have a sorta thing I do to check fuel pumps.

Requires 2 people. 1 person cranking/starting the car, while one keeps his ear close to the gas cover or gas tank.

You'll hear something if it's correct, I suppose. If anyone can correct me on this or whatever or think its wrong please do reply.

Other than that, thats what I do.


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