OK gents, I have a bit of a pickle on my hands here.
I have one sick 190E 2.6 and have a busy month ahead of me at school.
This leaves me to take my car into the main dealer, which I've had a great history with. Normally, I like to try my own luck first, as I've done a few jobs on my own with great success.
I have a brutal stumble at idle, when the car has warmed up to operating temperature (82C or so). After it reaches this temperature, the check engine light comes on and the stumble will occur at idle. Hesitation upon acceleration also happens, but after you reach 2000 rpm or so the car is smooth and strong.
I'm leading towards a water pump related problem. I read through the 3 or so pages worth of threads, and the car has some of the symptoms. The serpentine belt is noisy on the car, when you put it in gear that noise becomes louder. I'm not sure if I'm seeing a little coolant or not from underneath since it is winter up here and I'm always in a lecture or lab so I never can get a good look under there. Water pump is original
The car has 219,000 km on it now. Alternator replaced 20,000 km or so ago. Head gasket 10,000 km ago (along with the idle speed sensor). I did the plugs and wires on it 30,000 km or 2 and a half years ago. All electrics operate well on the car.
Serpentine belt has been on it for 60,000 km now, I did it 4 years ago. I did the tensioner at the same time. What do you think guys? I'm wondering if it could be the coolant temperature sensor? Everything electronic on it is original.
I rarely drive it now that I've moved so close to the University, I drive the car once a week or even less, and for a maximum of half an hour (to my part-time job).
I was thinking of dropping it off at the workshop and asking them to due the water pump, accessory belt idler pulley assembly, serpentine belt and tensioner, coolant flush, oil change and to run a star diagnostic to code pull for the check engine light. That is $2K CDN worth of work (or thereabouts). I don't think I'll be able to make an RRSP contribution this year
Have I overlooked anything do you think?