When i accelerate my blazer doesnt accelerate smooth, on the highway with the cruise on the rpms are higher than normal and fluctuate always being higher than normal. This doesnt happen all the time but the majority of the time it does. I replaced my catalytic converter, im not sure what the problem could be? Someone mentioned an electrical problem but i dont know how to know for sure or what to do? Any help would be great!!!!! Thanks!!!!!

 

What do you drive?

 

WOW, sorry, lol. 1999 S10 Blazer 4WD.

 

Does it do this at any particular speed or pretty much any speed?

 

any speed, its just more noticeable on the highway with the cruise on. Its kinda jerky and the rpms go up and down around 200 or 300.

 

Sounds like the torque converter clutch is locking and unlocking. This typically happens around 45-55mph, but shouldn't happen if you are in 1st or 2nd gear (torque converter clutch doesn't lock up in these gears).

Can you get it to go away for a bit by tapping the brakes just enough to turn the brake lights on, but not slow you down or taking your right foot off of the gas pedal? This will cause the torque converter clutch to unlock for a set amount of time.

 

it happens in all gears. It hasnt been as bad since i replaced my catalytic converter.

 

I had a similar problem with my 95 4x4 blazer but my transmission fluid was low. Transmission fluid would be a good place to check to help rule out the easy stuff. When you check the fluid note the color and if there is a burnt smell or even derbis in the fluid it could be a good indication that something more than electrical might be at fault.