Has anyone had trouble fouling spark plugs on a 4.6 V-8 with the C&L Cold Air system? I have 24K on my car and have been running the 93 Performance Tune with Amoco /BP 93 octane fuel. I started noticing a small miss under load around 5800 RPM. I pulled the #2 plug and it looked pretty burned up. No nitrous, super charge, just the 93 performance tune. Your thoughts? I’m taking it back to the Ford Service tomorrow (after replacing to stock) for them to take a look at it.

1 BAD 05

 

Not enough info. I need a pic of the plug.

 

Who is your tuner?

 

I know a person that fouled his plugs because he was using an octane booster.

 

Don't know if this is your issue, but after the new "gas" (15% Ethynol, or something like that) I noticed the gas mileage in my 06 GT went down and I could sense a slight miss under initial acceleration. (I have a C&L w/ 93 SCT Torque tune from Doug.) I emailed him with my concern and he sent me a "newer" tune that seemed to correct my issue.

 

I can't add anything, but I would sure like to hear what the dealer has to say about it!

 

I've noticed a small decrease in mileage when I use BP/Amoco gas, even though it is "recommended" by Ford. don't know if thats related but it is strange. Also my salesman/dealership owner (pays to have friends in high places) says he won't use it because it makes his new model T-bird spark knock. strange.

 

That happened to me also with octane booster took about 20 miles to foul the plugs.

 

I have read in other forums where 2 people had the same problem as yours. They changed out the plugs and problem went away.

I wonder about some of these tunes- we don't drive at WOT all the time (or do we?). Who is doing dyno runs at partial throttle in different gears, under different loads, to look at the A/F ratios around town? I would bet that some of these tunes are not put together as well as we would like to think they are, because the amount of testing and tune manipulation involved in creating pefect A/F ratios under all driving conditions would be cost prohibitive- only Ford has done that!

It worries me that they sell tunes based on dyno graphs that are based only on WOT- it really makes no sense at all for a street driven car. Example: My C&L 93 Octane tune is great when I floor it, but I cannot upshift very well at all (huge delay), because somebody forgot that the RPM needs to drop when you take your foot off the pedal for the gears to synchronize on an upshift- I guess that doesn't matter on the dyno, right?.

This is why I will eventually buy the SCT Pro kit and begin the long journey of creating my own, perfect tune.

 

I have wondered the same thing. Theoretically the engine should maintain an AFR of 14.7:1 during "non-performance" operation just like stock. There is no advantage to running richer than this at idle or during other light throttle conditions, yet I know that this is not the case with my Bama performance tune since the exhaust wreaks.