Q: 3.1 chevy park it revs fine, put in gear, idles good, won't rev ? on 1994 Chevrolet Corsica

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It runs great at park or neutral, but in any gear it dies like it has been shut off by either gas or spark. but if you give it full power it takes off like it should. So you have goog power at idle and a little aboue then no power floor it and it takes off. I have been a mechanic for 50 years and this is past me. I'm to much old school!!! Please help,Thank-you
(3) Answers
(3) Comments
burnt valve generally though could be throttle position. if this developed slowly over a short time then it is probably a valve.