82 300cd - intermittent power loss - PeachParts Mercedes-Benz Forum

derherr65 · #1 07-07-2006, 09:55 PM

I'm having issues again. My first though was that the large clear tube(dunno the name...boost reference hose maybe?) that runs to the intake manifold had blown off again, but it has not. The problem is intermitent, sometimes no power for minutes, sometimes on and off a half dozen times in 3-5 seconds. Other times it runs like normal. It's also running just a hair rough.

Any suggestions?

derherr65 · #2 07-09-2006, 09:30 PM

It is most noticable under acceleration, and occasionally at high speed cruise.

P.E.Haiges · #3 07-09-2006, 10:02 PM

der,

I've had a similar problem in a '79 300SD. It was very intermittant. Not the low power for minutes but the on and off power for a few seconds when engine was warming up. It felt like an old distrubutor gasoline engine with bad points.

I never found out what it was as it always cured itself before I could try to anaylize it. Very unDiesel like, I've never seen another Diesel engine act like that.

P E H

derherr65 · #4 07-10-2006, 11:26 AM

I'm a little suspicious of the fuel enrichment circuit. I've had a fuel pump go bad on a gas engine and it feels just like that. From what I understand the cruise circuit is mechanically set and the accelaration circuit is referenced to boost... somehow. I'm wondering if that boost reference device is failing.

derherr65 · #5 07-10-2006, 01:12 PM

I'm too used to gasoline engines. They sputter, cough and surge when starved for fuel. By comparision diesels just don't make power. Those symptoms above... replaced the fuel filters and it's happy now.