when i bought my car i was told it was tuned but ran real bad, i was told it needed to be retuned. Well i had it tuned and ran good but seems to be dead at part thottle now and idle jumps around some times now, and it did back fire out the pipes the other day.
Does a tune change after time, i didnt think it did , how does it do this or why
Tunes do not go bad. They are what they are, you had a bad tune to begin with and it just took awhile to affect driveability. You do not specify how your car was "retuned". If it was tuned on a dyno then there is a good chance that part throttle was untouched or just glossed over. My advice would be to find a different tuner or purchase a tuning suite on your own. Keep in mind that a part throttle tune takes longer and will therefore cost more if you have a pro tune it for you.
it was tuned on a dyno and put 3 passes on it there. the car when i cruise in like a higher gear seems dead down low and you need to give the car a lot of gas to get the car to move. I know he said he pulled some timming out up high and put some in mid that all i know.
I agree that tunes do change (slightly) with the season, but not enough to make a "good" tune go "bad".
I think the seasonal tune change is more due to changes in available fuel and not due to the tune itself. I know of cars that were thoroughly SD tuned in the summer and rechecked in the winter to be within 2% (via fuel trims) of the summer tune, so it can be done.
i just put ngk 6 plugs i think thaey are in [colder then stock ] about 500 miles if that .
thanks
Was there any specific reason you went with the TR6 plugs? What were they gapped at? You could throw in some TR55s to see if that clears up some of the problems you've been having.
I agree that tunes do change (slightly) with the season, but not enough to make a "good" tune go "bad".
I think the seasonal tune change is more due to changes in available fuel and not due to the tune itself. I know of cars that were thoroughly SD tuned in the summer and rechecked in the winter to be within 2% (via fuel trims) of the summer tune, so it can be done.
If your vehicle was mapped properly in the first place these issues would not be present. This is why the modern fuel injection systems of today adjust for conditions such as changing air density like it was spoke about above by using sensors such as MAF, MAP, and IAT.
Tunes do not go bad. They are not transient.
However airflow, timing (limited), and fuel "learning" does occur. If a tune is not correct, and accurate, as the car "learns" with driving time it's manners may deteriorate. The tune did not "go bad" - it was inadequate from the start.
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does a tune go bad or change
