Faulty fuel pump?
Thread Starter
Racer
Joined: Jun 2014
Posts: 328
Likes: 2
From: Mesa AZ
Faulty fuel pump?
Went to the Goodguys today and hit heavy traffic on the way home. For about 10-15 miles we were at a standstill: 5mph to 25mph and until I hit the 202 East I could run up to 65-70mph. Parked in the garage and when I shut the car off it sounded like "sloughing" in the rear of my 88 verte.
It lasts found about 5-7 seconds and then shuts off. I started it up again and it made the same noise. No hesitation when idling nor no miss or sporadic problems on the way home. Does this sound like a fuel pump is going out? Problem is I can raise the car but can't crawl underneath to check the filter. My back is shot! Any and all suggestions advised will be appreciated!
Tommy
It lasts found about 5-7 seconds and then shuts off. I started it up again and it made the same noise. No hesitation when idling nor no miss or sporadic problems on the way home. Does this sound like a fuel pump is going out? Problem is I can raise the car but can't crawl underneath to check the filter. My back is shot! Any and all suggestions advised will be appreciated!
Tommy
Thread Starter
Racer
Joined: Jun 2014
Posts: 328
Likes: 2
From: Mesa AZ
Re: faulty fuel pump
My 88 verte has been shut off for about an hour now and I went out and started it up again and it sounds noisy for about 5 seconds. When I shut the car off, it sounds as if the fuel pump is still pumping fuel through the fuel line.
Tommy
Tommy
Max G’s
Joined: Nov 2008
Posts: 2,751
Likes: 79
From: Monroe OH
NCM Sinkhole Donor
I don't think the fuel pump will stay running with the ignition switch off. You could do a pressure test but if you cant get under the car, it would be difficult to lean over and hook up the pressure guage too. Maybe you should take it to a reputable shop in your area if you have concern.
Safety Car
Joined: Apr 2011
Posts: 3,660
Likes: 22
tried the gas cap?
the pump does NOT run after the key is OFF.
the tank CAN build pressure or a vac that tries to vent thru the gas cap. Next time, see if loosening the cap changes anything...you may need to look at the vapor recovery system and the cap.
the pump does NOT run after the key is OFF.
the tank CAN build pressure or a vac that tries to vent thru the gas cap. Next time, see if loosening the cap changes anything...you may need to look at the vapor recovery system and the cap.
Thread Starter
Racer
Joined: Jun 2014
Posts: 328
Likes: 2
From: Mesa AZ
Tommy
Race Director
Joined: Apr 2002
Posts: 10,036
Likes: 346
From: Anaheim CA
Sounds like the oil pressure switch is still seeing enough pressure (or it's bad) to keep the fuel pump running after shutting off the ignition.
The fuel pump relay should open immediately when the ignition is shut off. That cuts off power to the distributor and the ECM will shut off the fuel pump relay when it no longer sees DRPs (Distributor Reference Pulses), which come from the ignition module inside the distributor.
The fuel pump relay should open immediately when the ignition is shut off. That cuts off power to the distributor and the ECM will shut off the fuel pump relay when it no longer sees DRPs (Distributor Reference Pulses), which come from the ignition module inside the distributor.
Thread Starter
Racer
Joined: Jun 2014
Posts: 328
Likes: 2
From: Mesa AZ
Sounds like the oil pressure switch is still seeing enough pressure (or it's bad) to keep the fuel pump running after shutting off the ignition.
The fuel pump relay should open immediately when the ignition is shut off. That cuts off power to the distributor and the ECM will shut off the fuel pump relay when it no longer sees DRPs (Distributor Reference Pulses), which come from the ignition module inside the distributor.
The fuel pump relay should open immediately when the ignition is shut off. That cuts off power to the distributor and the ECM will shut off the fuel pump relay when it no longer sees DRPs (Distributor Reference Pulses), which come from the ignition module inside the distributor.
I will try changing out the oil pressure switch as it has been acting a little goofy anyway since my return from Ca. Will give it a try and see what happens. Thanks for your help!!!
Tommy
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