QuestionQUESTION: I have been told that my son's car needs a "valve job". We had the mystical code "misfire on cylinder 5". My question is can you give us a best/worst case scenario in terms of cost? We don't want to agree to a $1K job and then find out it is 2K. Also, is this a could time to also do the timing belt? Finally, we are contemplating just trading in. Does it have any trade in value? (before this it was worth 4-5K trade-in vai KBB). Thanks in advance for any help.
ANSWER: How did the dealership determine a valve job is needed? Did they do a leakdown test? misfires normally relate to an ignition problem, so I would definitely just go for a second opinion. If a valve job is indeed needed, then yes the timing belt should be done at the same time. Trade in value seems about correct, but don't forget if you trade in a vehicle you don't get the discount leel on the car you're buying. Keep the trade in comment until the last moment. Cheers, Jan
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QUESTION: Thanks for the reply. I don't know if they did the test. The mechanic focused on it being a fuel injector problem. Once the injectors were in, he said it was 'just blowing through" and said it was low compression (hence valve job). Took out the fuel injectors and put it back together. We are taking for a 2nd opinion. We drove it home with engine light on/poor acceleration. Is it safe to drive 35 miles for our usual mechanic? I read poor compression could also be timing belt/timing chain problems. There is white smoke that comes out of the tailpipe. Course we live in VT so it could just be the temperature:)
AnswerA timing problem would affect all cylinders. Unless there has been a problem with a piece of spark plug coming off, or other debris in one cylinder, it is VERY UNLIKELY that one cylinder problem is due to valves. If the timing belt somehow jumped a tooth, then it is possible that two valves get bent in one cylinder by being hit by the piston while the others are OK. So your engine has a belt, but it is almost as much work to check it's timing position as it is to go the next step which is replace it. So this gets expensive. However if you have a misfire on one cylinder, and you know which one it is, I would switch the coil packs, leads and plugs around to see if the problem moves too; then you can troubleshoot if it is an ignition problem, compression problem or a fuel problem. Also do a compression check between all the cylinders to see if the suspected cylinder has compression, that is an easy start. If everything is connected correctly, and you want to drive it 25 miles, I would say this is probably OK but of course the engine is down on power so I'd recommed a leisurely drive with a backup plan in place; towing gear, trailer or friendly local tow truck driver... Let me know, Jan
