Cold Weather Misfires?

[NDblackstang]

Anybody have problems with misfires on a supercharged car in cold climates?

Put in my KB blower last spring. Ran great for 3,000 miles (qll last summer) but started to misfire this winter--driveability quickly deteriorated until I couldn't top 50 MPH. No problems with vacuum, coils, etc, but the plugs were fouled with black soot. I got codes for left bank rich, #6 misfire and random misfire. Replaced plugs and ran great for about 100 miles or so, but now starting to misfire again at higher RPM and throttle (no codes yet, though).

I installed Autolite HT-0 plugs (one heat range colder than stock) as recommended by Kenne Bell, but am wondering--is it possible these plugs are too cold for use on short trips in a cold climate? Most of my trips since these problems started are a mile or two, with the longest being 20 miles. Temperatures have been mostly below zero, with a few days as low as -20. I'm wondering if the plugs are not retaining enough heat to burn the fuel completely, starting a snowball (pardon the pun) of plug fouling and misfires.

I am considering putting the stock plugs back in. I run 8 PSI of boost. Any advice?

[jimmy_beaner]

I'd say it's worth a shot. Granted, temps are starting to warm up now, but you may as well try it. Also, if you're getting a sooty build up, you may want to seafoam the car to clean it out just before you change plugs.

Plus, it's not like plugs are expensive.

[NDblackstang]

Unfortunately, the plugs ARE kind of expensive--at least 100 bucks a set for Autolites. I definitely don't want to have to put in a new set with every gas-up.

KB says I shouldn't use the stock plugs due to detonation, but I wonder if they are just being ultra conservative. They say 99.9% of most problems are due to vacuum leaks, but I think I'm good there. I also haven't messed with the KB tune, which I suspect might be on the rich side to be conservative.

What is Seafoam?

Also, how did you get the picture of your car to show up on your post? I tried adding a photo of mine to my signature, but it doesn't show up when I post.

[jimmy_beaner]

there's something in your user CP called sigpic or something like that. As far as seafoam, it's a cleaning agent they sell at like any auto store. It'll clean out the carbon deposits. Since you said you're getting some on your plugs, it might be a good idea to clean shit out. It's like $7 a can. I had no idea your plugs were that expensive. I spent like $30 for a new set of 8 just 10 days ago.

[05RedDevil]

Stock style plugs are pretty check but when you get down to those colder range plugs they are about $100or more for all 8. Raw deal but no one said modifying a car was cheap

[NDblackstang]

That is a fact. Of course, it softens the blow if your $6K investment doesn't run like %@#! 3,000 miles after the install! I heard I need to gap my plugs to make my problem go away--ordered the special gapping tool from PMP yesterday.