Nuts and Bolts with Buffalo Jim

Hi, Buffalo Jim:

Rumor has it that you're the Cadillac man, and I've got a problem with my 1987 Cadillac Seville. I've tried three times, and it absolutely will not pass smog. I asked a mechanic, and he said I probably needed a valve job and it would cost as much as $1,000! Is there anything else that might be causing the problem? To be honest, I'd rather get rid of the car than pay that much.

--Dennis Lowry

As it turns out, bro, all the answers you need are on your failed smog certificates (so hopefully you didn't tear them up and toss them in the trash). There are two separate tests in a complete smog check. The first is for hydrocarbons (HC), which is raw gas. The second is for carbon monoxide (CO), which is partially burned gas. If you have a CO problem, that's coming from the combustion chamber. But if you have an excess of HC, it's either a valve or an electrical problem.

If you have valve issues, the HC reading will be high at idle, but will even out at a higher RPM reading. On the other hand, a bad spark plug, incorrect spark timing or a disconnected spark plug wire will give you a high HC reading across the RPM spectrum. If you suspect a valve problem, you can tell for sure by having the cylinders tested for compression. If one comes out significantly lower than the others, you're either going to have to part with your dollars or your vehicle. Sorry for the bad news, bro, but a bad smog check can be as cruel as a Dear John letter or an eviction notice.

Buffalo Jim is the owner of Allstate Auto Marine. If you're driving around on Halloween and you happen to run across a house with tombstones, a smoke machine and a life-size robotic Buffalo Jim, you've just discovered where the Buffalo roams. Drop a car question in his mailbox or e-mail them to buffalojim@lasvegasmercury.com.