my 300sl every time when cold would start and run fine, shut it off after running a few minutes and start again, sometimes would not accelerate without stumbling really bad. ordinarily I hate intermittent issues. so I take a wild guess and order in a new cam sensor, ezl temperature sensor, and being that I already had a distributor cap I got a rotor. I started with the cam sensor and low and behold the part that I was charged for a few years back because of an oil leak crumbled when I removed it. All the crooks did was put sealant where it goes into the engine. these people screwed me so bad on this and other things to the tune of about 4k, they are one of the reasons I learned to work on Mercedes myself, guess I should thank them. they aren't the only crooks I have dealt with in the past. anyway the cam sensor seems to have been the problem, after a month of perfect acceleration I conclude that was it. I didn't install the other parts I purchased yet. keep in mind this type of black plastic is used though out the 129 and in time fails.

 

stumbled again after over a month of running well. replaced nasty looking cap and rotor and as before when replacing cam sensor, runs good. only time will tell, love those intermittent problems. checked connection on the mas module and ran some sea foam through it to clean the fuel system too

 

still doing good.