Tech / General EngineIs your car making a strange sound or won't start? Thinking of adding power with a new combination? Need other technical information or engine specific advice? Don't see another board for your problem? Post it here!
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If my car has 3/4 of a tank or less. I get a whining sound comming from the gas tank after the car is shut down. Its some type of pressure build up. Buy turning the gas cap a little counter clock wise, the pressure vents, a strong smell of gas occurs and the whining stops. strangly, this does not happen in the cool of the morning when i park at work. However, park at home in the afternoon and it happens.
Anyone have this problem and figured it out. I'm guessing some pressure relief system is not working correctly.
Mods:
Suspension: Eibach pro kit springs, KYB struts, shocks, and TDS wonder bar, SFC's
Induction: K&N air filter, 52mm throttle body, port matched SLP runners and plenum. AFPR
Exhaust: Hooker headers with Jet-Hot, Catco cat, and Hooker Cat-back.
Tranny: built up 700r4 with Trans-go shift kit
cooling: Griffin radiator,185 Degree therm, 200 degree Fan switch
Future modes: New seats
Under your car by the fuel tank look for a white color vent valve toward the driver side. This is the vent for your gastank. It may not be venting properly. There not very expensive. Have to get them from the delaer tho.
__________________ ABird4U2NV
1989 Formula Firebird (RIP 11-8-05)
1991 Camaro RS
Goodwrench Crate 350 4bolt main, Comp Cam .454in/ex, Pete Jackson Gear Drive, Edelbrock Performer RPM Intake, Carter AFB 750cfm, Accel HEI, Hedman Hedders, Gutted Cat, 40 series Flowmaster, 700R4(Almost to be freshened and built), 10 bolt 2.73 Open(Another issue all together)
Mods:
Suspension: Eibach pro kit springs, KYB struts, shocks, and TDS wonder bar, SFC's
Induction: K&N air filter, 52mm throttle body, port matched SLP runners and plenum. AFPR
Exhaust: Hooker headers with Jet-Hot, Catco cat, and Hooker Cat-back.
Tranny: built up 700r4 with Trans-go shift kit
cooling: Griffin radiator,185 Degree therm, 200 degree Fan switch
Future modes: New seats
maybe the gas cap is not venting properly.the whining may be the release valve working.try running it home w/out the gas cap & see what happens.just a thought.goodluck
Since u already replaced the fuel tank vent valve, have u made sure the Evap canister side of things is actually purging the excess vapor(pressure) from the tank.
Also a plugged or almost plugged fuel filter could cause the pump to strain as well.
Could try dead heading and seeing if the fuel system holds pressure at the pump when the key is off. If it drops quickly most likely the check valve in the fuel pump is bad.
Most of that doesnt count since u said its after you have driven that car and parked it. check out the evap can/purge valve.
The problem has become worse. The pressure is so great that the gas cap becomes damaged. It becomes hard to get off. After that, can't get the gap back on. The threads will not engage and the top of the cap just ratchetts.
Had the small black valve and the relay to the canistar replaced. No differance.
Mods:
Suspension: Eibach pro kit springs, KYB struts, shocks, and TDS wonder bar, SFC's
Induction: K&N air filter, 52mm throttle body, port matched SLP runners and plenum. AFPR
Exhaust: Hooker headers with Jet-Hot, Catco cat, and Hooker Cat-back.
Tranny: built up 700r4 with Trans-go shift kit
cooling: Griffin radiator,185 Degree therm, 200 degree Fan switch
Future modes: New seats
I'm having this same problem, only I'm sure the whining is the fuel pump, which was just replaced. After about 15 minutes of driving, the pump starts whining. After about 45 minutes of driving, the car stalls at a stop and is very difficult to restart. When is does re-start, the engine does not run normally and chugs, like it is gas-starved. This situation is accompanied by lots of pressure in the tank. My mechanic is at a loss and says he checked the vapor cannister valve. I have searched... does anyone know of other causes, other than the pressure relief valve (gm pn 100333125) or the cannister valve? Please help... first it was the tranny, then a new fuel pump to replace a recently installed one and I'm almost broke...!!
__________________ original, but recently rebuilt 305 TPI flat top pistons 1.94" intake stock heads Comp 256 cam Custome 4000rpm T conveter Edelbrock TES headers with 3" Edelbrock cat back 700-R4 manual shift reverse pattern 3.23 10 bolt rear 16" 20 Slots w/255 BFG G-Force
I beileve the pressure relief valve at the axle is for sucking air in, not venting it outwards. It keeps a vacuum from forming in the tank. The bad side is that driving your car in deep water (or from a flood) can result in the tank taking a big ole drink of water. Don't ask me how I know. :-(
__________________ In the land of the blind, he who has one eye is king.
In my tank the line to the canister was plugged in the sending unit, I capped it off and spliced a "T" fitting into the line going to the vent in the back, connected that to the canister
we wrapped the muffler to block the heat from boiling the gas in the tank. this was another symptom.... i could hear the gas boiling after the car wouldn't start. it would only bog down, it must have been a vapor lock situation... i've driven around town and on the freeway for about an hours with only the slightest whine from the tank.
