Has anyone else had a problem after changing out the spark plugs?

I have a vt s/c on the car and went with nkg r 45672a-8 7173 plugs. I gapped them at about 0.032

I reset the ecu.

I have since noticed a slight decrease in power (butt dyno). Today I got on hard for a while. It was the first time I beat on the car in about a week or so since I changed out the plugs.

I was racing a wrx, and while the clutch was slipping (stock clutch). But it was unusual for it to do so from the 2 -3 shift. While it was slipping, the check engine light caught my eye, it was blinking about 4 or 5 times. I shut it down. And the light stayed off. I scanned the ecu and there were no codes.

Any ideas?

To avoid the question later for those who think it matters... still beat out the wrx, but it didn't seem to have the same pull.

 

maybe its just the heat.......

 

Flashing CEL means you're getting misfire.

I had the same thing happen on my car with vortech S/C a couple of weeks ago. I kept it in the 7-8K rpm for a while (trying to keep up with my buddy's R1) and then the CEL light started to flash. I also use NGK 7173 plugs.

When I released the thottle, the CEL light went away.

My guess was that it was the heat due to sustained high rpm or some sort of fouling.

After that it ran great and had no problems.

Just change them often....

 

Getting a misfire after changing plugs can be attributed to several things:
-you could have damaged one or more of the plugs when gapping them.
-the plugs are not torqued in to the proper spec (did you use any anti-seize?).
-one or more of the coil packs could have been damaged in the process.
-one or more of the coil pack wiring connectors are not locked in securely (this has been reported being done by a Honda tech no less).

After checking the above and getting no joy, you should then double check all the connections at the ECU where the Vortech black boxes are spliced in. Comptech guys have been having a heck of a time lately due to inadequate connections. Vortech is no less suseptable.

 

Thanks for the responses. The gapping seems about right for a s/c motor right? ~0.032

I checked everything today, maybe number 3 clip to the coil pack was loose? I got on it today a few times, and I could not recreate the blink. Afterwards, I was at a light for about 3-4 minutes at idle. When I pressed the gas from that light, it hesitated a bit, but no idiot light (also I was not doing any high reving).

As I was going home,I kept the car in 2 nd gear for a mile or so with rpm's inbetween 5 and 7k to make boost and try to heat soak the intercooler. once in the driveway I let it sit idle for a couple minutes. then I tuned off the car, and opened the hood to check the intercooler fluid temp. I didn't have a thermometer, but the fluid was VERY HOT. I'm thinking that heat soak from the engine could go into the intercooler, and since the intercooler radiator sits ontop of the engine radiator, it's possible to transfer heat and warm up the intercooler fluid that way as well. Then since there is no air moving through to cool it down possibly intake temps were too hot?

Does that sound like a possibility since the vt seems to run on the lean side to begin with?

 

Sitting still with no air movement through the rad will make the chargecooler heat up easily. Then, when you move off, the intake air is still very hot. You are experiencing the same as what any NA car would experience sitting in stop and go traffic. Next time, if you want to minimize this, activate the air conditioning so that the fans are turned on. This way, even while sitting still you are drawing air through the rad. You should be able to feel a difference.

 

good idea! Thanks