2004 KJ rough idling

[jmorales]

My jeep starts fast but after about 5 seconds starts shaking pretty bad. Ive changed the spark plugs, gapped and torqued correctly, as well as the ignition coils, but didnt fix the problem. I tried adding one of the techron fuel cleaners but didnt feel a difference, shaking still as strong as before. Anyone have an idea what it could be or what I could try?

 

[LibertyTC]

Have you cleaned the throttle body & IAC/ports?
Is the engine light on? Any problem codes?
Any valve clicking noises? Compression test? How many miles on this engine?

 

[slamgranderson]

If there's a misfire, you should get some engine codes that indicate which cylinder is misfiring. Aside from spark plugs and ignition coils, you could pull a fuel injector or two to see if they're fouled up and need to be cleaned or replaced.

Also, go over all your vacuum lines, you could have a leak somewhere.

 

[jmorales]

Thanks for replying guys

I have cleaned the throttle body, but Ill give the IAC a cleaning tonight, see if that helps. No CEL, engine has 130,*** miles

Ill also pull a couple of the injectors and see how they look

Might seem like a dumb question, but which are the vacuum lines?

 

[RenKJ]

Thanks for replying guys

I have cleaned the throttle body, but Ill give the IAC a cleaning tonight, see if that helps. No CEL, engine has 130,*** miles

Ill also pull a couple of the injectors and see how they look

Might seem like a dumb question, but which are the vacuum lines?

There are two vacuum lines on the right side of the intake plenum seated just behind the throttle body. They plumb into the neck that the throttle body bolts into, one runs to the brake booster and the other runs back over engine to the T connection that splits into the crank case vents at the back of the block ( you can put a oil catch can on this one to keep intake a bit cleaner)