What is causing subaru backfiring severely after head job done?

Asked by Jul 02, 2012 at 09:05 PM about the 2002 Subaru Legacy L Wagon

Question type: General

Blew heads on '02 subaru. Had replaced. After job done car starting backfiring severely. Severity increases when under load, especially when using air conditioner. Threw code saying third cylinder misfiring? Guy who did job said it was first, the plug. Nope. Then said it was the plug wire. Nope  Is still doing it and getting worse. I think it's the cylinder itself. Any ideas what else it could be?

2 Answers


hmmm well the thing might be 1 check out the electric wires out from the battery to the engine see if that needs replacing. 2 the spark plugs check them out. 3 see if there's any wear or damage to the engine and i mean the whole thing if 1 thing is out of place ur going to have problems 4. question for ya how many miles are on the car and what have u been doing to it for the last 10 yrs it might explain ur problems

the valves could be tightened too much, should be checked out

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