Originally Posted by
velociabstract
I decided to update this old thread of mine, seems more efficient this way don't you think? I've been getting a rear P0136 O2 sensor cell. The first time I got this cell it was a leak at the manifold to downpipe flange. (It's not leaking now) It often pops up when I use 100 octane. Lately I have to clear the cell every day so I decided to change the plugs and use the stock gap this time. (.040) The pictures show a rich condition .... or it's the meth/100 I use at the track. I couldn't say for sure. However, my wide band tells me the car is running a bit lean. Hum. I marked the plugs in the order they came out just in case I found a problem and checked the gaps. All were at 0.35 except one that was .037. I guess I'd gotten in a hurry on the last one when I gapped them down. The cars running strong and hopefully stronger now. Here's a picture of the plugs.
Les
Those look like a set I removed back when I ran slow at the 1/2 mile event. The low boost was causing the car to run fat and the plugs were black. Anyway, back then I just purchased new plugs and swapped them out, but I kept the old plugs. Since the new plugs sold with the old car, I decided to clean the old plugs and install them in the new car. Anyway, they seem to be running fine.
By the way, I never had any CEL's though.