All, I'm having a problem with an 1981 Mercedes Benz 380SL It seems to run relatively smoothly at idle (with a little irratic-ness) but on the highway, once you get it to speeds, it begins to hesitate as if it's not getting enough fuel.

I'm thinking there is a fuel blockage issue but the pump appears to be new.

When I put a c/o meter on, a 10 degree turn anti clockwise will result in moving the c/o mixture from 4% C/O to 0.2% C/O.

I purchased this car for a buddy who has to drive it to Wisconsin in a couple of days.

Any thoughts would be appreciated.

__________________
With best regards

Al

Low fuel VOLUME can cause that type of issue.

With the engine running ON the return side, there must be 1 liter in 25-30 seconds.

Also a bad dist cap, rotor OR coil can cause the same symptoms

__________________
MERCEDES Benz Master Guild Technician (6 TIMES)
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MB Doc, as always, you give great advice.

Today we did a fuel flow test and could fill a 1 liter bottle with gas in about 18 seconds so it's all good. We checked the timing at 1500rpm and at 3000rpm and it was within spec.

The coil was not a Bosch coil (instead one made in Mexico). As we had only noticed this problem while the engine was hot, we replaced the coil with one that I had lying which was taking from one of my SLC 5.0's and then took it for a drive.

Problem solved.

David S Poole also provide some telephone support which was also very useful. Thanks you both for your help.

__________________
With best regards

Al