So I get this "AirCell" throttle body spacer for Christmas. I go out, take off the air intake, lift off the throttle body, put the spacer in and button 'er back up. As I'm testing it, I hear the dreaded whistle. So I figure the o-ring they sent with it was crap and I pull it back into the garage, take it off until I can find a better o-ring for it. The next morning my check engine light came on and it read "Code P0351 - ignition coil A primary/secondary circuit malfunction." First off, which coil is coil A? Is it on the front of the engine on the passenger side?
The truck ran great until I put that damn spacer on. Now I get a low idle when I'm at a red light, but it doesn't stall at all. And it's kind of sluggish. Now I'm afraid I'll be in the middle of nowhere for work and it's going to crap out on me.
I cleaned all the connectors with QD cleaner, clean the MAF sensor off with MAF cleaner, checked to make sure all the coil packs (which I believe are the round modules on top of the spark plugs) where on snug and the connectors were on good. I even cleaned the connectors on the throttle body and checked the tube that runs from the air intake into the passenger valve cover.
I have a 2004 (new body style) SuperCrew with the 5.4. No other engine mods on it except a K&N drop-in filter.
Any tips or ideas?
Thanks guys and gals.

Romer
Coeur d'Alene, Idaho

 

It's the #1 coil, first one on the passenger's side. Make sure it's plugged up.

 

Take that spacer off and throw it in the trash can.

 

Already done GLC.

 

Did you fox the P0351? My have P0351 rigt now I will apreciate your help

 

Art, you need a new COP on #1.

 

I only switch COP1 for COP 5 and fix it! It had to be a loose contact. Thanks!