I finally broke down and put my car in the local Chevy dealership. The diag. Team looked at it and they said my hesitation problem is due to the computer retarding the timing. However, they were really busy and didnt have time to finish there diag. I talked to the tech and he thinks there is a problem in the EST system. He also said the tech 1 scanner was always detecting a knock. My question is I can't hear or feel a knock is it possible a knock senor is going. Or my est module. As a side note I got a code 42 about a week ago but the light only stayed on for a few minutes. Any opinion, Brandon

By the way its a 90 with a 305 TBI

 

hey yall, let me know whats up!! i have the same problems!! please feedback will be appreciated.

 

Formula, I will let you know as soon as find out. I am just wondering if it is the knock senor, the esc module or the ecm. Brandon

 

24 years later and you never let us know I don't mind waiting but this is a lil much!