1985 Fuel Question!!!
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1985 Fuel Question!!!
I got a Fuel question for yall. When i turn my car to on position to check fuel pressure it is at 36psi. Then when i start it, it goes down to 30psi. Any recomendations for my problem? i was thinking it was a leaky injector, but not exactly sure. What U Think?????
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Is the car not running properly? Symtoms? check engine light?
Le Mans Master
Joined: Mar 2004
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From: Dublin CA
Are you checking with the vacuum hose to the FPR disconnected and plugged? Should be.
Does the pressure settle in at 30 PSI when running and hold at that pressure? I would not think it is a leaking injector...this would also show when you turned on the key. The pressure would drop if the key was just in the on position for awhile.
When was the last time the gas filter was changed?
Does the pressure settle in at 30 PSI when running and hold at that pressure? I would not think it is a leaking injector...this would also show when you turned on the key. The pressure would drop if the key was just in the on position for awhile.
When was the last time the gas filter was changed?
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It dies and wont start back up
yea, the car starts fine then after about 10 secs it trys to die so i have give gas to keep it alive then after about 30 secs it dies. I can start it again if i pump the gas then it dies after 10 secs then wont start back up.
The Check Engine light is on but for some reason i cant read the codes. I have taken it to get computer scan and they said it could read the computer. I have connected the A, & B, Terminal and still cant get the light to blink to read codes.
I changed Oil couple days ago and the oil had more fuel in it than oil! I have changed the spark plugs. check fuel pressure.
The Check Engine light is on but for some reason i cant read the codes. I have taken it to get computer scan and they said it could read the computer. I have connected the A, & B, Terminal and still cant get the light to blink to read codes.
I changed Oil couple days ago and the oil had more fuel in it than oil! I have changed the spark plugs. check fuel pressure.
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85 Problems!!
I turned the key on and it was at 36 turned it off and it started droping slowly. Turned it back on it jumps to 36 then start it reads 30psi.
I have just recently bout the corvette So i dnt know how long since gas filter has been changed.
When I start it it runs for about 10 secs then trys to die out so i have to give gas then after about 20 secs it dies. I can start it again by cranking and pumping on gas, then after bout 15 secs it dies and wnt start back up, and it seems to be flooded.
I have just recently bout the corvette So i dnt know how long since gas filter has been changed.
When I start it it runs for about 10 secs then trys to die out so i have to give gas then after about 20 secs it dies. I can start it again by cranking and pumping on gas, then after bout 15 secs it dies and wnt start back up, and it seems to be flooded.
Melting Slicks
Joined: Oct 2004
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From: Austin Texas
what is your FP doing when it dies ? Doe's it stay at ~30 psi or drop down to 0 ?
sounds like your FP or FPR has gone bad......need more infor. though.
Woh dog : " I changed Oil couple days ago and the oil had more fuel in it than oil! "
this is a serious problem....!!! you need to find out how you got so much fuel in your oil.
sounds like your FP or FPR has gone bad......need more infor. though.
Woh dog : " I changed Oil couple days ago and the oil had more fuel in it than oil! "
this is a serious problem....!!! you need to find out how you got so much fuel in your oil.
Last edited by MikeC4; Dec 7, 2008 at 09:35 PM.
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oil
I would be concerned why you have gas in your oil. Be careful. Fuel in oil can wash oil off of surfaces and cause internal damage.
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If an injector is leaking down, this might explain the fuel in the oil. When he turns off the car fuel may leak in the cylinder.
You really should do a leak down test on these injectors and see if I’m not correct.
Why the pressure dropping when running? Possibly the fuel pressure regulator, if the hose is connected and it may be a faulty injector. There may be more than one problem here. I don’t understand this sentence “I have taken it to get computer scan and they said it could read the computer. “ Did they read the codes and if so what were they. If they couldn’t read the computer it gets even more interesting.
Willcox Inc.
You really should do a leak down test on these injectors and see if I’m not correct.
Why the pressure dropping when running? Possibly the fuel pressure regulator, if the hose is connected and it may be a faulty injector. There may be more than one problem here. I don’t understand this sentence “I have taken it to get computer scan and they said it could read the computer. “ Did they read the codes and if so what were they. If they couldn’t read the computer it gets even more interesting.
Willcox Inc.
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Melting Slicks
Joined: Oct 2004
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From: Austin Texas
Now i believe what Willcox is telling you may be your problem. It sounds like an injector is stuck open and bleeding gas into one of your cylindars. Do you notice rich gas smell out of right or left exhaust when cranking over ? Pull your fuel rail and injectors out, intact, get 8 glass containers or some rig to catch the gas spray, and turn ignition on but do not start engine. Look to see if injector is leaking. All injectors should be closed at this point. You can also crank over for a short duration to observe spray from injectors and then turn engine off to observe for leakage. Fuel pressure for remain for many hours and bleed down very, very slowly.
Let me ask you again ....what is your FP doing when it dies ? Doe's it drop to ~30 psi or does it rapidly "bleed down" down to 0 ?
You need to be very methodogical about troubleshooting this issue, or you may ruin your engine if you continue running a gas/oil mix.
Let me ask you again ....what is your FP doing when it dies ? Doe's it drop to ~30 psi or does it rapidly "bleed down" down to 0 ?
You need to be very methodogical about troubleshooting this issue, or you may ruin your engine if you continue running a gas/oil mix.
Last edited by MikeC4; Dec 8, 2008 at 12:49 AM.
Team Owner
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From: Summerland B.C. Canada
This will help you isolate the pressure loss. The pressure #'s listed are for an 86, 85's pressure should be in the 30-35lbs.
http://members.shaw.ca/corvette86/Fu...mDiagnosis.pdf
http://members.shaw.ca/corvette86/Fu...mDiagnosis.pdf
Race Director
Joined: Jun 1999
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From: Merritt Ils Fl
Are you absolutely sure you are shorting A & B terminals in the ALDL connector? If you are you may very well have an ECM issue. Short terminals--- turn key to run not start Check Engine light should flash Code 12 three times then fault codes. Please check again.
Le Mans Master
Joined: Aug 2007
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From: WV
This question was asked on another site by Cherokee Corvette and I answered that I thought it was a injector leaking, I don't know of any other way for gas to get into the oil other than an injector, someone please correct me if Im wrong. WW.
Pro
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From: Mt Prospect IL
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Let's go back to the basics. If the fuel pressure is 36 with the key on and 30 at idle and the FP regulator vacuum line is hooked up, this is normal. the bigger issue is the loss of pressure after shutting off the car and no access to codes by jumping the ALDL connector. Check all fuses, I had a car with a blown fuse to the ECM and could not pull codes even though the car ran and tripped the check eng lite. You need the communication with the computer first, then you can diagnose the fuel system problem. Good luck!
Le Mans Master
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From: Phoenix AZ
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This sounds like a bad intake gasket, and a bad injector.
1. if the gasket is bad, the thing won't run because of the massive vacuum leak.
2. when it quits, and the injector is leaking, the manifold gasket is allowing the fuel into the oil.
OR
he has a cracked intake manifold, cracked head, or just a plain ol' mystery.
1. if the gasket is bad, the thing won't run because of the massive vacuum leak.
2. when it quits, and the injector is leaking, the manifold gasket is allowing the fuel into the oil.
OR
he has a cracked intake manifold, cracked head, or just a plain ol' mystery.