Hi friends,
Just replaced the cat converter, plugs and fuel filter at rail!
The van ran great for two days and now does not want to go hwy speeds! Will idle like its new, but when I hit the accelerator, it just boogs down really bad! Hesitates and makes back fireing noises in engine compartment when put through the paces!
Need some help with this one! I love my van,,,bought it new in 01 and it has 160k on her! Any ideas!
timbuctwo

 

What's the exhaust sound like? Might be some upstream crap has clogged the new cat.

 

You said you replaced the plugs, but how about the plug wires? In my experience, bad wires cause a lot of stumbling on acceleration. Fire the engine up in the dark and look for arcing. If you see any sparks, change the wires.