P0422 code. Results of compression and MAF test.

[AdlerV70]

Following some advice on solving my CEL light issue(P0422, no others) (Engine runs smoothly but my mileage is shit (Ave 15.5) and power seems lacking)I did spark plug check, cylinder compression, and MAF tests today. All plugs looked good except #4. On that one the electrode looked good but the ceramic and shoulder were coated with a thin layer of brown schmutz, and there was more in the module boot. Looked like cooked engine oil. I cleaned them both up and made a note of it.
Compression test went well (thanks for the link!) and the results were;

#1-190
#2-185
#3-180
#4-180
#5-190

None showed any bleed down. I did get a small whif of fuel after number three but got closer and really smelled and got no more scent.

So, I put the modules back on. #2 kept popping back up so I bolted it down, started the car, and it ran just as before. So I moved on to the MAF test. I read a few places that if you disconnect the MAF at idle whether the engine dies or not gives a good indication of the state of the MAF. Here are those results;

Engine idling @1100 (Normal for this car) and cold
Disconnect (DC) MAF pigtail, engine hiccups once, smooths out, idle now @900.
Reconnect (RC) MAF, 5 second delay then engine idle revs up to 1000 and stays there.
DC MAF again, engine hiccups once, dies.
RC MAF, restart engine, idle @900
DC MAF, engine dies, then hiccups
RC MAF, restart engine, idle @ 900

Thoughts? Do these numbers point to anything in particular?

[draser]

You should have fuel on the plug, to answer the fuel question, and pull the plug and stick it into the coil, lay on the engine and start and look for spark.

[AdlerV70]

Draser,

Thank you for the quick reply. I found the problem and edited my post. When I bolted down the #5 module (the one under the big black plastic tube (turbo?)) I pinched the black wire for the #4 module under the bolt. All better now other than feeling pretty stupid...and lucky.