CarTalk.com Blogs Car Info Our Show Deals Mechanics Files Vehicle Donation

Infinity '93 vibrates

My Infinity '93 sedan vibrates at idle and also at various speeds. There are no service message lights. Mechanic says there is spark and fuel at idle on all cylinders, except 2 cylinders have no compression. He suggested may be camshaft, but would be costly to even find that out. Any ideas?

Your mechanic’s theory sounds reasonable. I would think that a definitive diagnosis of low compression could be obtained for about $100 of shop time. It involves a compression and leak-down test where they check to see where the leaking air is going (intake/exhaust/or crankcase). If it is not leaking anywhere, then the problem is a cam.

The trouble is that most problems that cause low compression will cost more to fix than you would likely be willing to invest in a car of that age. If the car has over 200k miles, this may be the end of the road.

It can be difficult to drive a 16 year-old car unless you are a do-it-yourselfer. You are often faced with tough decisions on big investments without complete data on the extent of the problem.