Hi 2 weeks ago my 1993 240 b230F started having problems. I started it and it had a rough idle. No fault codes. Tried with a friends AMM and it ran fine again. Drove 100 kms and then bought a new one and droveanother 50 km. This was a few days later. Went to start the car again oen day and it had a sort of rough idle again. Fault code 133, and the car wouldnt idle, since the code means problem with tps, i just changed the whole butterfly valve housing with a different tps switch. Now the car would not die at idle but still runs rough, and it is running rich and black smoke out the exhaust pipe. I have tried with new plugs, different plug wires, coil, ignition module, both ECUs, checked that timing belt hasnt slipped, measured O2 sensor (stays at 0,9V almost all the time, guess this is because its obviosly getting too much fuel.), checked for vacuum leaks found none, changed injectors cause i had 113 fault code at some point (no change), i have also tried with different fuel pressure regulators with no difference . coolant temperature sensor is only 3 months old but i am going to check it. Anyone that has any suggestions what could be wrong? i as of now the car runs rough at idle and alot of black smoke and fault code 133

 

noone that has any suggestions?

 

No idea. Try checking fuel pressure, if you can?

 

Does your model have a fifth cold start fuel injector? If so check if it's either stuck open or being opened by the temp sensor

 

Hi thanks for replies! luckily i found the problem today, its was my new AMM that was faulty (not of best quality) tried with my friends bosch and the car ran fine again, so i will be ordering a bosch now

 

Great glad you solved it! I had a similar experience with MAFS and sometimes I feel like a broken record dealing with running problems where guys have issues and swear they changed the damn things with no good results then discover it was the MAFS after all! I went through all that with all the gurus saying everything else until I started swapping everything and once the MAFS was changed, all good! Lesson is, the MAFS cause many undiagnosable issues with our cars and they are basically impossible to test and many times the "new" ones are bad as well!