Hey all, I have a '98 Blazer 4.3L 4x4 auto w/109,000. When I accelerate past 1/4 throttle it seams to be very sluggish as if tranny might be slipping. I tried slowly accelerating and everything shifts fine. When I giver heII the RPM's jump up and she tries to gain speed but very slowly. I have no check engine light and just did a tune-up with single platinum plugs. I cleaned theMAF sensor already. I have had TPS and fuel filter replaced at 43,000. I just recently changed tranny filter also. I am runung into a wall with a diagnosis. Please help! Thanx, Cory

 

what does the code read from the engine service light? Check your EGR valve. i am goin through some what of the same issue right now/

 

Bad torque converter ? Clogged cat might be the problem to.

 

Thanks! I will do some more digging to find problem. I was thinking it could be be a fuel problem. Is there a way to check TPS, or fuel pressure regulator? It seems to be lacking in power on certain spots in the pedal. The cat was rattling lately, I should check that out as well.

 

That's my problem. Check engine light does not come on. It came on for MAF sensor and I cleaned that. That cleared the light but did not fix my problem. I will have to keep looking. Does anyone know if I take it to a shop and have them hook it up to a scope, will it show up? I would think it would but might have to take it toa "professional" technician. I like to work on my own vehicles, I trust myself more than anyone else.

 

It will trip a code when you clean it thats no problem. Maybe your fuel pump is failing.

 

When was the last time the air and fuel filters got changed?

 

I replaced fuel filter@ 50,000 and have aK&N air filter. I just cleaned thatas well.I am thinking it could be cat but not sure. I am also leaning towards fuel pres. reg. or TPS? I just don't want to throw parts at it so I might take it in to the shop for a diagnosis. I appriciate all of the reply's to my problem. The more brain power involved the better the outcome! I'll keep you posted.

 

Might as well change the filter again, it's about due, methinks... and it's not all that expensive...

Spark plugs?

Did you check to see if the cap and rotor are still in good shape in the distributor?

 

I just did complete tune up and everything looked fine. Plugs were even in the normal range. It can't hurt to change filter. Not a bad idea, considering were we get our gas from. Who knows what is in those tanks at the station.