I have 1 96 trailblazer which I had bored over .020 head shaved and removed starter and oil injector. When I removed the oil injector I could not get the gear out of the case so i packed it with grease and installed the plate. About 1 1/2 hours into my first ride with everything done the engine began ro idle way to high the only thing i could do was turn the choke on and it came back down to idle. This makes me believe air leak. Can air be getting in through the oil injector block off plate. Or any other suggestions Thanks.

 

I would suggest pressure testing the engine to determine where the air leak is.

 

[img]i/expressions/face-icon-small-disgusted.gif[/img]I had the same thing happen with my xplorer. I took it to the dealer, he adjusted the ETC, told me everything was fine, charged me $50, sent me on my way. Well, guess what, first ride and you guessed it same problem. This time I started looking for myself. I found a crack in the boot between the carb and motor. I replaced it myself and everything was back to normal.

 

Could the oil block off plate be the source of an air leak.