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1986 rough running

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Old Mar 22, 2009 | 07:58 AM
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1986coupe
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Default 1986 rough running

I have a 1986 that has some running issues. It barely runs but doesn't throw any codes. When I disconnect the MAF it runs fine except that it has difficulty starting when it is hot.
I have tested the fuel pressure on the fuel rail and it reads 40psi. If I leave it connected it will drop to about 25psi in about 1-2 minutes.
The injectors are reading the proper ohms.
Any thoughts?
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Old Mar 22, 2009 | 11:53 AM
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Originally Posted by 1986coupe
I have a 1986 that has some running issues. It barely runs but doesn't throw any codes. When I disconnect the MAF it runs fine except that it has difficulty starting when it is hot.
I have tested the fuel pressure on the fuel rail and it reads 40psi. If I leave it connected it will drop to about 25psi in about 1-2 minutes.
The injectors are reading the proper ohms.
Any thoughts?
Look in a FSM. There is a diagram list on determining
if its a maf issue. I have had maf issues with out codes before. Sometimes, when you dis connect maf and it runs better is also a indication its a maf issue. JMO.........................
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Old Mar 22, 2009 | 08:50 PM
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perform the time honored tap test. put it in, start the car, tap it with the handle of a screwdriver. If it falters or runs better, it's the circuit board inside. could be a poor solder joint, or a component
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