1991 300E-24V bucking and stalling

[stevangus]

Hello People. My 1991 300E-24Valve Sportline sedan has been a dream to run for the last year, however, about 4 weeks ago, after about 6 minutes into a journey, it started rough idling. Every time i Stopped, the engine would hang, sometimes catching itself before stalling, sometimes not.

On moving away, the engine would cough and splutter, before sorting itself out after a couple of blocks. This happened 2 weeks later, again about 6 minutes into a journey (in the middle of the busiest street in Melbourne - of course!). It took longer to sort itself this time, about 4 miles, but then ran like a dream.

Last week it happened again (10 minutes into the journey and during ruch hour). I parked up, swithed off the air-con which helped cut down but not stop the stalling when I put it into drive and neutral. Took about 25 minutes to sort itself out.

I took it to my mechanic who replaced the fuel filter. There was lots of cloudy crap, so we hoped that was the problem. Yesterday (approx 80K's since the last time) It started doing it again. Once again I was forced to park up, play with the air-con and rock back and forth between 1st and reverse until it cleared up. This time, the radiator light came on about 10K's after the event and stayed on for about 10 minutes while driving. It switched itself off. I have checked coolant levels - all okay.

Has anyone had similair problems to this? My next step is to perhaps replace the plugs and the coils. My mechanic and I are resigned to replacing my car bit by bit until we get to the problem.

I was hoping some of you could share some insight to the most common reasons for this so I can at least be a little targeted in my approach

Some extra info - the car has an imobilizer and I installed an after market kenwood head about a year ago (full stripping out the seperate control & head unit wiring and completely re-wiring the speakers!)

Thanks in advance