Hello, I am new to this forum and find it amazing. My MB is a 1989 260E with Automatic trans and has 500k on the clock. Before I bought it I was allowed to drive it for a month(very generous of the seller), no problems at all were found, in fact I got addicted.
we did a compression test and 180LB all the way across.
It needed new injectors wich we replaced, also new plugs and Oxygen sensor. It has passed emisions test easy.
The problem started yesterday, it started to run rough. It is smooth running for the count of four seconds, then it appears to cough or sputter for one second then smooth again for four. It cycles like that repeatedly.
Any help would be appreciated.
Thank you.

 

cycling on and off? I had a RPM variation situation on a 96 W202 and it was finally identified as the A/C comprssor cycling off and on every few seconds. The cause: Overpressurization of refrigerant. This happened in very warm conditions.

With the onset of late spring/summer are you using your A/C for the first time or do you have warmer temps for the first time?

When your engine is doingh this cycling, open the hood and check to see if the A/C compressor clutch is cycling on/off.

 

thank you for the reply, no, I do not see the compresor turning off or on. It seems the engine is about to stall it is so rough. Then it is smooth as silk. Any other suggestions would be welcome.

 

Sound like it could be a fuel filter... With that many miles on your ride you should ask the last owner the last time its been changed.