I’m getting a vibration that’s mostly noticeable in front end, and I’ve exhausted every diagnosis. I’ve replaced the cap, wires, plugs, (she was due for) idle air control valve, and TPS. It’s not a harsh vibration, but it’s still noticeable. She runs smoothly while driving. Any ideas would be greatly appreciated! I’ve also smoke tested her, and no leaks. The only smoke comes out of the throttle body butterfly which is normal, I’m told.

 

Your plenums blown….take a flashlight and look into intake, see any oil? Shouldn’t be there… If so plenum gone…that smoke test was also an indication

Bad plenum can clog cat, in turn screwing with o2 sensor, which can effect ignition components

 

Definitely not blown. I ran all the tests. No pooling of oil, or vacuum in the valve covers.

 

Did you route the wires according to the TSB? There’s a certain way to route because wire arcing can happen

and you did look into the intake right? You’d need a flashlight…..this is a design issue, it will blow, they all do

 

Yes I did. Again, no pooling. I know that because I had the Hughes plenum repair kit installed a while ago.

This is my routing. I followed the FSM.

 

There’s a TSB (technical service bulletin) that the manufacturer released….the wire ends aren’t what I’m talking about, it’s how you route the wires to the plug

 

What plugs did you put in?

 

And, when you replaced the idle air control valve, did you clean out all of the carbon/muck in the throttle body well area before replacing the valve?

 

Champion copper plus.

 

Yes, I did.