I have a 98 blazer 4x4 with 148k miles. ran fine until one day i noticed engine revving harder to move from a stop. sometimes acts up and takes a lot of time to get to 55 mph. gotta let off gas some at times to get up to speed. can anyone help a Marine diagnose this problem. dont want to get raped at repair shop if it is something like a plugged cat converter. 6 months ago got engine tune up at dealer and replaced plugs with ac delco plats and plug wires and got throttle body cleaned so i dont think its in the engine. now service engine light came on three days after topping off tranny fluid (wasnt low extremely, just needed a little to read full. thanx for any help.

 

Did you have the codes read when the check engine light was on? If so, what were the codes (Pxxxx)?

 

Yes, check the codes, but sounds like it could be the cat. I just recently had the same problems and it resulted in the cat breaking loose and partialy plugging the muffler. I heard it rattling before it acted up. If you tap it and it sounds loose it probably needs to be repaired.

 

Welcome Jarhead.
Keep answering the questions and we will get you going in the right direction.
Semper Fi.