Red hot Glowing Precat on 300TE - PeachParts Mercedes-Benz Forum

Merkey · #1 12-01-2006, 12:57 AM

My son posted a problem a week ago, but I wanted to repost and ask for more info.
Here is how it looked..

To recap.... he was around town... her drives carefully... car suddenly started to run rough... lost power, so he stopped and pulled the hood.

As a father, I was worried that something was wrong... but, next day and since it has run normally.
Duty cycle is about 40%. It is using oil about 500/quart, due to valve seals...

Any ideas?

Ron in SC · #2 12-01-2006, 06:32 AM

This is just a guess but could the CAT or muffler be substantialy blocked due to some sort of breakdown or failure and thus cause the problem.

manny · #3 12-01-2006, 10:16 AM

If you have severe misfires for an extended period, you will overheat & eventually plug the catalytic converter.
Believe it or not, I have seen a converter plugged solid on a Chevy, within 100 miles, because the owner ran the vehicle with a defective coilwire.

Merkey · #4 12-01-2006, 11:09 AM

Thanks guys....
Is that the "precat" and what is inside it?
As I said, we have an valve oil seal issue which we plan to do over the christmas break.
I find it hard to believe its plugged... wouldnt it run like this all the time then? What would it be plugged with and would it clear itself?

Matt@Revolution · #5 12-01-2006, 11:12 AM

It's plugged with oil. Should have replaced valve seals earlier.

suginami · #6 12-01-2006, 11:57 AM

You can order a full exhaust from the intake manifold back, including the cat, from www.timevalve.com

Merkey · #7 12-01-2006, 09:43 PM

Thanks Matt.
I agree, maybe we should have replaced the valve seals sooner. Sadly, my "ability" to place my hand on the valve cover and somehow sense the failed seals remains underdeveloped.

suginami · #8 12-03-2006, 03:29 PM

Here a shop forum member with a full exhaust to sell from his 1990 300TE.

Just posted today:

Fs: 1990 300te Complete Exhaust