Thanks for your reply! I still don't think it's the ISC/CC. You could of course be right but I'd be really unlucky.
I do not have ASR so that is out of the question.
Also the cruise control works perfectly. I've tested this a few times.
Thanks for your reply too!
You might be onto something here with these vacuum leaks. I think I'm a bit of a newbie with the vacuum system so I would need some
help there how to diagnose this
As my brakes are not the best I have done several things to improve the braking (front brake pads + lube, rear brake pads and new brake hoses + brake fluid this weekend). It's still not very good but as part of diagnosing the brakes I have done a test which the guys on the Dutch w124 forum told me: With the engine off, step on the break a few times until the pedal feels hard, start the engine and check if the pedal goes down, which it did. Would that be significant enough of a test or do I need to check some vacuum lines? If I do, how do I check them spray something or?
I do not have a EGR valve or a smog pump, maybe that's the positive side of having a euro spec M104
Also, not sure if this is important but I'd thought I'd just say it anyway. When I bought the car the gas pedal felt weird. The first bit when you press it felt loose/soft and then it would give a lot of gas. Some guy from the Dutch forum adjusted the cable when I was at his garage getting some second hand 8 holer rims. Later I tried adjusting it a bit myself according to some workshop manual, it felt much better but I'm not sure if this can have any impact on my problem.