Possible fuel pump problem
Thread Starter
Racer
Joined: Dec 2004
Posts: 470
Likes: 0
From: Phoenix Arizona
Possible fuel pump problem
Last couple of times I've filled my tank when opening no pressure, previous to that I would notice what I would call a reasonable amount of pressure when releasing the cap. Also I have recently noticed a low whine while driving coming from the rear of the car. It is not berings, nor u-joints, does not happen all the time just perodically. Could this be my fuel pump having early intermittent problems prior to failure. I have a fuel pressure gage attached to the schrader valve and the pressure is between 38 to 40# at idle with 24# Bosch injectors. Also noticed the car started (previously) the instant I turned the key, now it must crank for 4 or 5 seconds prior to the start. Do not want to get stuck in 110* Arizona heat.
Thanks for the help..............
Thanks for the help..............
Le Mans Master
Joined: Jul 2007
Posts: 5,043
Likes: 7
From: Tampa Florida
For the long crank times:
Check the leak down times on the fuel rail after you turn the engine off. It should stay around 38 psi for at least a 2 min. if not you've got address this first.
High pitched wine noise from the fuel tank:
My car ('89) did this for about a month and so did my girlfriend's car (2000 Firebird) - the cars made the exact same noise but only at idle and only on really hot days (90 degrees F & up). The cars themselves also had to be hot (over 200 degrees F and up). The cure: - - turned out it was caused by crappy gas 87 octane....switched over to midgrade of 89 octane and problem vanished. Just for kicks, I put the crappy 87 octane back in to see if it made the noise again and sure enough....it did. No more crappy gas for me.....I'm guessing the problem is caused by the new/alternative method/chemicals of refining gas.... near as I can tell the older cars don't seem to like it much.
Check the leak down times on the fuel rail after you turn the engine off. It should stay around 38 psi for at least a 2 min. if not you've got address this first.
High pitched wine noise from the fuel tank:
My car ('89) did this for about a month and so did my girlfriend's car (2000 Firebird) - the cars made the exact same noise but only at idle and only on really hot days (90 degrees F & up). The cars themselves also had to be hot (over 200 degrees F and up). The cure: - - turned out it was caused by crappy gas 87 octane....switched over to midgrade of 89 octane and problem vanished. Just for kicks, I put the crappy 87 octane back in to see if it made the noise again and sure enough....it did. No more crappy gas for me.....I'm guessing the problem is caused by the new/alternative method/chemicals of refining gas.... near as I can tell the older cars don't seem to like it much.
Le Mans Master
Joined: Feb 2006
Posts: 8,753
Likes: 9
From: Louisiana
For the no pressure when opening the gas cap, check to make sure the EECS is working correctly. The wine from the tank sounds like a dying fuel pump. The longer cranking times could be injectors or a failed fuel pump relay.
Instructor
Joined: Jul 2007
Posts: 174
Likes: 0
From: Toronto Ontario
sock is clogged
The sock in the tank is probably clogged. The reason you hear a whine is because fuel pump is having a hard time sucking fuel thru a clogged in tank fuel pick up filter (AKA the sock). Replace it and whine should go away.
