idle engine knocking

[Bradley Bliton]

I installed the screamin demon coil pack, livewires, and modified throttle body. I also installed my volant cold air intake and performance spark plugs. Now when I have my ST in park and it is sitting there idling. I sounds as if my truck is looping or knocking. I have no idea what the problem could be. I also bought a bypass breather kit for my ST and had that installed but took it off and reinstalled the OEM bypass breather tube. When I had the bypass breather kit on there was an open hole in the piping of the cai. I don't think the open hole would throw off the mass air flow sensor. But I am not sure. When I drive my truck it drives just fine and there is no engine knocking or looping. If anybody has any ideas or suggestions please let me know. I appreciate y'all and help you give.

 

[Dave S 2]

High performance spark plugs???

 

[Tom Schindler]

Not saying I told you so, but I would point at your plugs.





Tom

 

[Rodger Tellefson]

What plugs did you use? Also, did you disconnect the battery for at least 20 min. in order for the engine computer (PCM) to reset itself?

 

[Bradley Bliton]

The idling engine knocking was doing it before I installed the spark plugs. I had only installed the aftermarket throttle body and the volant cold airintake. Yes I had the battery disconnected for more than 20 minutes. I also have a check engine light on. Anybody know what the cause of that could be? I believe my plugs are fine.

 

[Gavin Allan]

Put it all back to stock and see if it runs OK.

 

[Todd Z]

The open hole will cause an issue, the engine is sucking in un-metered air that the MAF is not reading...



Also the plugs could be playing around with it..



Todd Z

 

[blert]

Plug the hole with a rubber cap or plug...

Disconnect the battery to reset the PCM...

Fire it back up...

IF the CEL comes back on have the code read at a local parts shop (DAP, Autozone, etc...) and post the code back here before you buy any more parts.

 

[shawn stonbraker 2]

I'll bet money you have a plug loose. Mine had the same thing after changing the plugs, and low-and-behold, one of the bi*ch plugs (on the passenger side) still needed about 6 turns on it, even after I could have sworn it was tight.