PCM Fails to hold tune
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PCM Fails to hold tune After a heads and cam install, my buddy had paid a lot of money to repeatedly have his car tuned at a very reputable tuner. He even purchased a mail order tune from LG.
The car runs perfectly for the first day of the tune, but the more he drives the car, the more the car begins to run badly. If he disconnects the battery, the car runs good for about a day, then things begin to degrade again. Any ideas on what is happening?
The car runs perfectly for the first day of the tune, but the more he drives the car, the more the car begins to run badly. If he disconnects the battery, the car runs good for about a day, then things begin to degrade again. Any ideas on what is happening?
Fuel trimming and/or knock learning most likely; an aggressive
lean-out and timing push gets you performance but maybe does
not stand up, across the broad range of driving envelope. The
thing to do is get it hooked up to a logging scan tool and see
what the knock retard, knock learn, long term fuel trims and so
on are doing, drift-wise.
lean-out and timing push gets you performance but maybe does
not stand up, across the broad range of driving envelope. The
thing to do is get it hooked up to a logging scan tool and see
what the knock retard, knock learn, long term fuel trims and so
on are doing, drift-wise.
