90 Vette Bogs badly
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Le Mans Master
Joined: Apr 2000
Posts: 5,098
Likes: 1,351
From: New York New York
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90 Vette Bogs badly
Hi,
A friend of mine owns a 90. the car runs OK when cold, but when it gets hot the idle goes up and down a bit and when you go to take off it bogs badly and does not accerate no matter how much you press the accelerator.
There are no codes, someone tried a computer and the fuel pressure is 36 PSI at idle and when you rev the engine it goes to 41-44 PSI. When you disconnect the vac line off the pressure regulator the pressure only goes to 44 PSI.
It feels like it could be the fuel pump.
Any suggestions? I own a 61 with a carburetor and this is out of my ball park.
Thanks.
A friend of mine owns a 90. the car runs OK when cold, but when it gets hot the idle goes up and down a bit and when you go to take off it bogs badly and does not accerate no matter how much you press the accelerator.
There are no codes, someone tried a computer and the fuel pressure is 36 PSI at idle and when you rev the engine it goes to 41-44 PSI. When you disconnect the vac line off the pressure regulator the pressure only goes to 44 PSI.
It feels like it could be the fuel pump.
Any suggestions? I own a 61 with a carburetor and this is out of my ball park.
Thanks.
LS/MFT
Joined: Jun 2000
Posts: 5,874
Likes: 0
From: Cary IL
St. Jude Donor '09-'10-'11-'12
Fuel injector failure is common on this L98. Symtoms are similar. One goes, and because the injectors are wired in series, the others on the same side soon short out as well. Check the resistance of each injector -- any that shows less than 14.7 ohms should be replaced. The tear-down time is the same to replace all 8, so if the money is available, I'd do all of them at the same time.
LS/MFT
Joined: Jun 2000
Posts: 5,874
Likes: 0
From: Cary IL
St. Jude Donor '09-'10-'11-'12
Fuel injector failure is common on this L98. Symtoms are similar. One goes, and because the injectors are wired in series, the others on the same side soon short out as well. Check the resistance of each injector -- any that shows less than 14.7 ohms should be replaced. The tear-down time is the same to replace all 8, so if the money is available, I'd do all of them at the same time.
LS/MFT
Joined: Jun 2000
Posts: 5,874
Likes: 0
From: Cary IL
St. Jude Donor '09-'10-'11-'12
Fuel injector failure is common on this L98. Symtoms are similar. One goes, and because the injectors are wired in series, the others on the same side soon short out as well. Check the resistance of each injector -- any that shows less than 14.7 ohms should be replaced. The tear-down time is the same to replace all 8, so if the money is available, I'd do all of them at the same time.
Instructor
Joined: Jul 2005
Posts: 125
Likes: 0
From: St. Peters Missouri
Originally Posted by Vette73
Fuel injector failure is common on this L98. Symtoms are similar. One goes, and because the injectors are wired in series, the others on the same side soon short out as well. Check the resistance of each injector -- any that shows less than 14.7 ohms should be replaced. The tear-down time is the same to replace all 8, so if the money is available, I'd do all of them at the same time.
I had the same problem on my 90. Found the bad one and replaced only the one, what a mistake! Replace them all at once, its much easier in the long run...
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Thread Starter
Le Mans Master
Joined: Apr 2000
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From: New York New York
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Thanks for all the replys. We are trying a coolant sensor and will ohm out all the injectors.
We are also going to open up a flange on the exhaust before the cat and see if it makes a difference.
I will keep you posted.
We are also going to open up a flange on the exhaust before the cat and see if it makes a difference.
I will keep you posted.
