hey i got a 91 civic std. i just did a y7 swap...i used the old intake mani. ...
the car starts and idles fine, (sometimes,others its irratic). when i rev it, it revs ok ,sometimes, and most of the time it hesitates at about 2000rpm, when i started to investigate this problem, i started to get a backfire in the intake, followed by a flame...i checked the timing its fine, plugs and wires are fine...what else to look for!
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bty- the car ran fine with the old motor, the new motor ran fine also...
what to do,,,what to do?