ECU or transmission problem??

I had a problem with my Automatic 1996 C200 which was diagnosed as my ECU. The ECU got repaired (at 1st it was only firing on 2 cylinders, that got repaired and then only 2 injectors were working and that got repaired as the ECU repair is under 1yr warrantee).

On repairing the ECU the rev counter stopped working, but now car seems to be under fuelling (and stutters as well as won't idle without juddering or cutting out if engine isn't warm) and overfuelling (high revs). In addition it drags itself from 0-20 as it acts as if there is no power then all of a sudden jerks into action. It doesn't seem to change gear at convenience (i have to take my foot off the accelerator pedal then step on it again to change gear!!

Diagnosis says transmission is the problem. Is this related to the ECU? If so should i send it back to the repairers or is it transmission that is external to the ECU?? Any advice will be greatly appreciated.

MB's are normally a joy to drive and this is my 3rd after having 2 190's, but this is getting to be quite tiring now

 

I wonder if either the ECU repair is faulty or the wiring loom is breaking up so creating spurious signals and short circuits.

 

It does rather sound as the above is the problem,,do you have a good indie near you

 

Dieselman and Television, thanks for the advice

The indie I use did a diagnostic after getting the ECU back (as it didn't seem right) and it came up as a transmission fault but the rev counter also hasn't worked since they repaired the ECU (don't know if its related?). On slowing down to a stop while driving it judders and makes the exhaust system vibrate and rattle.
The company that repair the ECU reckon they had run tests on the ECU for over a week and couldn't find a fault since repairing it but the fact that the rev counter still doesn't work since they repaired it makes me feel this could be a relating symptom/indicator?

 

Hi what system is on the car pms or hfm, pms had problems you can get them repaired th.ough

 

Update on my C200 which I'm aptly labelling a "non-mover" now as it struggles to get up to 40mph.

Diagnostics on plugging it in to the digital machine: it came up with 2 engine codes
040 - ignition output 1, amperage not reached
050- transmission speed signal output short to battery positive.

Battery connections and wirings have been checked obviously, and all in fine working order. So it seems its the ECU that is still faulty as Dieselman initially said, if i'm correct?

 

Check your plug lead end but I would suspect ecu as above, we have seen many that have supposed to have been repaired but are still faulty, the problem is that they cannot test under load for a long period. we have test ecu's to prove a point.

 

Before the ECU got repaired we went through the process of elimination by checking the leads and plugs and replacing them with new ones (as the original fault started as the car only firing on 2 cylinders), then the coil pack. So the leads, plugs, and coil pack are all new to a degree.

 

Deff ecu then