A few months ago I bought a 1996 E300D, from a friend who was in a minor fender bender. . The body type is a model 210 ... 606.912 engine with 96,000 miles on it. After replacing the radiator, power steering cooling line, a new head light and a couple of weeks at a body shop for a new bumper; it’s back on the road.
Since it’s been back home I’ve changed the engine oil/filter and fuel filter.
However, there is one problem that has gotten progressively worse over the last two weeks.

The problem is: Engine Surge. At a constant RPM (seems to happen within the range of 1200rpms - 2500rpms) the engine starts to surg moderately. I first noticed it with cruise control engaged. On a level surface constant rpm the surging would start. I thought it might be a function of the cruise control so I experimented with manual control of speed either on level surface or on a grade up or down.
It didn’t matter what the grade of the road was, as long as a constant rpm was attained the problem would surface. Experimenting with the car parked and accelerating and holding an rpm within the above rpm range the engine starts to surge and quickly bog down as if it is being fuel starved.
The only action which remedies the problem is to continue to very the rpms either up or down.
It was suggest to me by a couple of people to put a can of Red Line Diesel fuel additive in the tank to see if that might clear up the problem.... Ok folks what do you think?? I'm running out of ideas and I really don't want to go to the dealer for an expensive evaluation.
Thank you

 

Joe, does the problem happen during the first few minutes the car is turned on, before it reaches full operating temperature?

 

It doesn't seem so. The last time I drove it (a few days ago) I tested it while it was cold and it didn't act up. However there are times when it is at operating temp. and it works fine as well. So far it seems to act up about 80% of the time when it's at operating temperature...
Thanks for the reply!!
Joe

 

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