Real Auto Dynamics
New member
I would recommend doing a compression test again on a warm, not hot, motor with all the spark plugs removed and the break booster line removed. Start with the suspect cylinder first.
If you determine the cylinders are okay then look toward the plugs. Replace them and and gap them to .028 in. Then I recommend a boost leak test or a smoke test be done. It is also good practice to clean the MAF sensor with some electrical contact cleaner and make sure your air filter is clean.
From the description of the stutter it almost sounds like it is fuel cut of some kind which would be the tune it self. Almost like it is over boosting in 4th gear and higher and then hitting a limit and fuel cutting. If all else can be eliminated you will need to take it back to where you had it tuned.
If you determine the cylinders are okay then look toward the plugs. Replace them and and gap them to .028 in. Then I recommend a boost leak test or a smoke test be done. It is also good practice to clean the MAF sensor with some electrical contact cleaner and make sure your air filter is clean.
From the description of the stutter it almost sounds like it is fuel cut of some kind which would be the tune it self. Almost like it is over boosting in 4th gear and higher and then hitting a limit and fuel cutting. If all else can be eliminated you will need to take it back to where you had it tuned.