PeachParts Mercedes-Benz Forum - View Single Post - '92 300D 2.5, does not altitude compensate & turbo drops out, EGR, ALDA?

Wayfarer · #1 08-09-2009, 06:15 PM

Hi all,

I have a '92 300D 2.5 with 320K miles on it that I've had since 90K miles. It's awesome and I want to keep it going as long as possible. Only major engine repairs are rebuilt injector pump at 177K and new turbo just at 310K.

A couple of issues I've had since about 125K (and had given up fixing) are:

1) whenever I drive the car up into the mountains, it is very hard to start and belches white smoke, as if it is set too rich, at sea level it runs fine.

2) the turbo goes out after 30-60 minutes of driving especially after highway driving.

As a result, I just stay around town and drive my Honda when on road trips or when I go up to high elevation. I had the dealer (here in Dallas) once try to fix the issues and I ended up buying a new diesel "brain" that didn't fix the problem (they wouldn't take the part back or give me a refund...long story). I've been up into the mointains a couple of times over the years and have always had the same problem.

So here I am after 10 years of living with this finally snifing around this site and getting some ideas. I'm starting to think the two problems may be interrelated.

Could my EGR be clogging up the ALDA, banjo bolt, switchover valve, or some combination thereof? Is there any way to check for proper operation or way to do easy service to clean them out? Also, what about just replacing these parts; are they all that expensive? I am not a whiz mechanic, but I could probably manage to replace these parts.

It's a great highway car and a shame I am restricted to short trips on the flatlands. I am moving to Boise and would really like to get this figured out once and for all, otherwise I'll probably have to leave my baby behind in Dallas.