Good afternoon:

I have a '92 300TE with 136K miles on it. I had the head gasket replaced when I bought the car at 110K, but it has idled very roughly ever since.

My mechanic suggests that the fuel injectors may be "weak" and should be replaced.

Other than burning some oil and the rough idle, all seems well.

Any thoughts as to a possible solution? Also, is it worth fixing or would the cost be prohibitive?

Thanks in advance for any assistance.

CMOSS

How does he come up with "weak injectors". All of them?? If you are burning oil, check the plugs. If they are oil fouled, that is your problem. depending on what they did when the head gasket was done, you may be looking at valve seals or possibly valve guides as well.

I'd find another mechanic who can tell you clearly what is wrong with the car. This guy sounds like the kind that throws parts at it until it runs better. Not worth paying $60/hr+ IMHO.

Sometimes a mysterious rough idle is due to a fault with the oxygen sensor(s), they can fail, or become fouled, or even have a loose wire connection, causing a constant changing of the mixture, and creating a rough idle. I would check them. Also check for a vacuum leak.

Bad motor mounts will cause rough idle, too. Yes, I'm not joking. Also wrong or worn out plugs, bad wires, dirty or worn out distributor cap and or rotor, clogged injectors............
You get the idea. Lots of stuff causes bad idle.
Did the wagon get it's 60k service at 120k? Where are you on your maint. schedule? You do have a maintenance schedule, don't you? :-O
I didn't think M104's burned oil like our trusty M103's. The 92 does have the 104 engine doesn't it? If it's the M103 I hope the tech replaced the valve guides and seals along with the head gasket. The burning oil might be the cause of the rough idle!
Doh!


[Edited by Hazen on 03-16-2001 at 01:48 AM]