So I have a crack on my exhaust manifold, an have had a rough idle ever since my header cracked, how much would a crack effect idle? Jould I check everything else too? Help!

 

Take off and clean your throttle body with TB cleaner as a first step.

 

X2

 

It could affect it quite a bit. I also have a cracked header and have replaced EVERYTHING else that could affect idle (TPS, IAC, o2 sensors, cat, all ignition components, motor mounts, put in a new sparkly bored throttle body, new injectors, etc etc you name it) and my idle is still not perfect. But it is always good to clean your throttle body and IAC. Easy to do and wont cost more than a can of throttle body cleaner and a new TB gasket. Also, do a tune up if you haven't in a long time.

 

Did new rotor, cap, wires, plugs, and I cleaned my tb yesterday, along with an entire clean up of my engine compartment. Also cleaned air filter. I have APN headers in route to my doorstep, going to replace motor mounts and header when it gets here. Hopefully this helps. Also used 'thermo-steel' for the current crack in my header, lasted a day. The shot motor mount doesn't help though. Hahaha (awkward laugh out of sadness for a not perfect running jeep) haha.

 

I'm sure doing the headers and motor mounts will help a ton

 

yeah couldnt wait for the motor mounts, they got bad. look at my last thread in the oem section. geeeeeeez. and was a ****ing hassle on the passenger side.