After long drives, my car starts to bog. Is that because of the CAT?

Ive changed the O2 sensor, checked the timing changed the timing belt. etc

I was curious what the sympotms of a bad knock sensor and map sensor are?


Modified by SSImpala at 8:30 PM 5/2/2005

 

any ideas?

 

1. Your IACV valve may be clogged (back of intake manifold. clean or replace)
2. If you have a FITV valve under your throttle body, do a search and clean it.
3. Unplug your emissions EVAP purge valve (should be around the black plastic canister on rear left of engine) and see if the problem persists.

 

Sweet thanks for the reply. Hopefull its something youve suggested.

Oh yeah, after the long drives, it idles really low and feels like it wants to turn off then the rpm flucuates up and down but it doesnt really turn off. I usually putt it in neatral and have to give it gas when it goes down to low. Im hoping somone could offer more suggestion besides the helpful ones suggested ablove? or narrow it down

I have an Ls with Automatic trannsmission. The Car, engine, transmission has about 170K on it. I'm curious if the transmission is going out? It performs normal when its cold.

Thanks