rough idle only when in gear

[lukecarr]

I do not know how to tell if the fuel pump is running except for the wining sound before the engine starts. I do have the jeep running rouger in the cold. I also have a rougher idle in geer with not rpm change, just like you had. I do have a problem when it is cold outside sometimes I have give gas to get the engine to start. When it starts is sounds like it could stop, for a for seconds, then just rough idle. Most of the time when it is cold outside it does sound rougher. How would I go by to check the fuel pump out? Thank you for your time. Sorry it took me so long to reply.

[lukecarr]

Originally Posted by collinb

Check your motor mounts, putting it in gear will normally put more stress on the mounts. If one is snapped it will not be able to fully absorb the vibrations.

How do I check my motor mounts? I am trying to learn.

[gunjes]

let me check to make absolutely sure of the voltage that is supposed to run to the fuel pump. I'll write as soon as I know. I never tried giving it gas ,as it is fuel injected and should run at 40 psi continiously (if you have a gauge you can check this at the fuel rail port). Anyway let me check and I'll write.

[Bernando1]

I don't think it is the fuel pump. I just replaced it, it is running at 40 psi. Any other ideas for the rough idle?

[lukecarr]

Could it be the pcv valve being cloged, or the ccv valve being cloged? I do get oil in my air filter.

[dksob81]

Yes deffinately
The PCV valve cause many slight rough idle problem. and it's only a few dollars. you could check it by pulling it out and shaking it if you can hear it rattling then it's good. You should be able to blow through one end but not the other.

If you gonna remove it, make sure to warm the engine first, this will loosen the rubber grommet to make it easier to pull out. I did this with the engine cold and end up breaking the PCV valve off.