Question about 2002 Pontiac Grand Prix

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Engine runs 1200 2000 rpms.rebuilt whole motor and still had same problem. so replaced tps and idle control also thermastat and temp sensor i get no reading on the obd connector it won't register i tried 3 different scanners could the computer be bad? it only acts up after one hour of operation the after a bit it goes to normal then all messed up again. there are no vacume leaks

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Check the computer powers and grounds and obd connector and engine grounds,if these are good its possible that the computer may need replacing as 3 scanners won`t read data and the obd connector is fed directly from the computer.

Posted on May 21, 2011


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