Need Help starting 85 TPI Corvette
Thread Starter
Instructor
Joined: Nov 2002
Posts: 119
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From: Horsham Pennsylvania
Need Help starting 85 TPI Corvette
I am helping a friend get his 85 TPI running after about two years,
the car will start right up, but then turn off about 5 sec after. I have checked all the general areas, Anyone know a possible cause or has had past experience. thanks
Elliot Thompson
the car will start right up, but then turn off about 5 sec after. I have checked all the general areas, Anyone know a possible cause or has had past experience. thanks
Elliot Thompson
Team Owner
Joined: Mar 1999
Posts: 22,025
Likes: 192
From: At the beach in little Rhody
Can you monitor the fuel pressure? The pump runs to pressurize and then will restart on oil pressure (if I remember correctly). Do you see any oil pressure in that five seconds?
Drifting
Joined: Jan 2007
Posts: 1,977
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From: Houston, TX www.djmotorsportaccessories.com Specializing in C5 & C6 Accessories. DJ Motorsport Accessories.
St. Jude Donor '08-'09
Try this question in the C4 section.
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
Try to read the DTC Codes. Jumper pins A to B in the ALDL connector under the drivers dash area and watch the flashes on the Check Engine Light (CEL) You will see it flash 12,,,12,,,12,, (then what ever codes are present and when it is done posting all the codes it will flash 12, 12, 12 again.
C4's are sensitive to loss of oil pressure (bad sensors), VATS problems, and fuel pressure issues (bad Fuel pump relays) which can cause this kind of problem. Monitor/read fuel pressure. Make sure it is at spec and stays there when you stop cranking.
The relays are easily swapped with other relays of the same PN#
Man,,,your making me clear out the cob webbs. it beem a LOOOOOOOONNNGGGGGGG time since I had to fix a C4.
i have an 85 service manual if youhave any specific questions.
BC
C4's are sensitive to loss of oil pressure (bad sensors), VATS problems, and fuel pressure issues (bad Fuel pump relays) which can cause this kind of problem. Monitor/read fuel pressure. Make sure it is at spec and stays there when you stop cranking.
The relays are easily swapped with other relays of the same PN#
Man,,,your making me clear out the cob webbs. it beem a LOOOOOOOONNNGGGGGGG time since I had to fix a C4.
i have an 85 service manual if youhave any specific questions.
BC
Instructor
Joined: Aug 2003
Posts: 220
Likes: 8
From: A little place called Macungie PA
Hey I don't live far from you, so if this gets really crazy I may be able to help in person.
I have an '87 Z-28 with the TPI 350 motor, to check the fuel pressure there should be a fitting towards the firewall on the pass. side fuel rail. When you first turn the key to the on postion the fuel pump should kick on for a few seconds and bring the fuel pressure to about 44-48 psi, this is before you crank the car. Once you crank the engine the fuel pump will not kick on until the oil pressure sensor tells the computer you have oil pressure. When that happens you should be running around 34-38 psi at idle. The fuel pressure value can have a wide range the important point to note is at idle it will be a little lower than the reading before you started the car. It adjusts based on engine vacuum. I've owned the camaro for about 12 years and there isn't a bolt I haven't turned so let me know if I can help with your TPI. As a sidenote besides the Camaro I also have a C5 so if it's a C4 problem and not a TPI thing I might be less helpful.
All the best.
I have an '87 Z-28 with the TPI 350 motor, to check the fuel pressure there should be a fitting towards the firewall on the pass. side fuel rail. When you first turn the key to the on postion the fuel pump should kick on for a few seconds and bring the fuel pressure to about 44-48 psi, this is before you crank the car. Once you crank the engine the fuel pump will not kick on until the oil pressure sensor tells the computer you have oil pressure. When that happens you should be running around 34-38 psi at idle. The fuel pressure value can have a wide range the important point to note is at idle it will be a little lower than the reading before you started the car. It adjusts based on engine vacuum. I've owned the camaro for about 12 years and there isn't a bolt I haven't turned so let me know if I can help with your TPI. As a sidenote besides the Camaro I also have a C5 so if it's a C4 problem and not a TPI thing I might be less helpful.
All the best.
