Hey there I recently got some issues with my W124. I thought it was the distribution cap and the ignition rotor since it did the same symptoms this time from last time my car stopped working. I bought new distribution cap and ignition rotor and got no positive results. I can get the car to turn on but wont stay steady and if I accelerate too fast the car will start to shake like its going to turn off and eventually it will.

My friend brought over his diagnostic check thingy so we could plug it in and figure out whats wrong with it but after searching and searching we couldnt find it. Turns out it needs some kind of code reader. I did the steps I saw online to get the light to blink but only got 5 blinks. I dont know what that means.

Did I mention that before this I didnt have any problems with my car?

Anyways what can I do to a diagnostic check on my car?