stumble getting worse.

.044" is the plug gap for a regular N/A protege and that's what the gap will be when you buy plugs.
 
I was going to suggest you check the plug gap. I had the same problem with my MSP. It wouldn't hurt to pull them and make sure they are NGK ZFR6F-11 gapped to .028-.032"

Cant remember if I checked this yet. I know when I had my first BP 1.8T I had not gaped the plugs right and it did this same thing almost. I guess I know what im doing in the next day or so. Not sure how I did not even think of this.
 
Yeah when I bought my car, it was spurting really bad when I stomped on it. The ZFR6F-11 plugs are the right plugs for this car, but they do come .044-.045. These cars need the gap closed because the high octane gas needs to ignite "later." The stumble I was experiencing was premature combustion from the plugs already in there. The wider the gap, the more tendency for the plugs to fire too quickly and cause that stumble.
 
Found my problem. It was a bad coil pack. Only $27 at advanced auto. Now it runs great
 
Yeah when I bought my car, it was spurting really bad when I stomped on it. The ZFR6F-11 plugs are the right plugs for this car, but they do come .044-.045. These cars need the gap closed because the high octane gas needs to ignite "later." The stumble I was experiencing was premature combustion from the plugs already in there. The wider the gap, the more tendency for the plugs to fire too quickly and cause that stumble.

The spark is 'blown out' under boost due to the higher velocity of air, the smaller gap doesn't allow the spark to be 'blown out'.
 
When I've needed coils it never threw a code. It would just run like crap. $60 and 5 minutes later 2 new coils always fixed the issue.
 
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