Dead Cylinder

[Schneidy95]

I just bought a 91 TT with 96 motor. Ran great for 30min. Then after a 2sec WOT the car was on 5cyl. The previous owner said he had the wrong plugs in it. so I swapped it out and still only on 5 cyl. this would be #1 cyl. I believe. I checked coil connector with test light, light came on. swapped coils and injectors and still only on 5cyl. Had a 34cel (knock sensor connection) bypasses it with resistor and code went away. Yet again running on 5cyl.. Checked compression and its only 120. Im guessing its blown? Im at wits end here.. Any help is very appreciated..

[ezb57e]

Well, 120 is very bad, if that's an accurate reading.
Pull ALL the plugs, make sure the battery is charged, and do a full compression test.

[Schneidy95]

just did it twice and got 150 this time.. cyl. above was 145

[ezb57e]

What were the other cylinders?

[Schneidy95]

well I took the connector off the cas and pcm and clean some of the dia. grease out because the previous owner packed it in there. and its on 6cyl again... I'm not sure if that did it or sea foam lol. I guess ill just have to wait and see if it does it again. thanks for the help!

[ZL8NING]

Good thing you figured it out! And thanks for coming back to mark your thread "solved"