New EIS + New Key: Still Has Non-Start Issue
 

This issue I have been having seems to be giving both the dealership and some mechanics a tough time. I have a 2002 c320 that is having an intermittent non-start issue. You put the key in, turn it all the way, and hope the car starts. Upon recommendation by both the dealer and some mechanics, I purchased new keys, however, the car still would not start sometimes. We then proceeded to replace the EIS, hoping that this would solve the problem. It did not unfortunately. The car will still sometimes not turn on. Are there any other factors that we might be overlooking? :confused:

Extra info: The starter has also been checked and seems to be functioning properly.

Hello and welcome to the forum Mike - when you brought the car to the dealership and they did their diagnostic test; what codes did they end up pulling?

Both the dealership and mechanic shops ran several diag test on the car, and each time they found no codes related to the EIS, starter, key, or battery. Just codes regarding other components like light bulbs, a/c compressor, and emergency system. Interesting observation though, I did notice that on the number of fault codes on the car display keeps changing. ( Typically showing 3 codes, then dropping to 2 codes, then moving back up to 4 codes, back to 3 each time the car is started) (Quite strange right?)

Maybe something is wrong with the entire computer? This issue does happen at random, so perhaps that makes it hard to get a proper reading.

That's really odd, I haven't heard of this happening before - if they cleared the codes all together and waited for a reset; would they pop back up?

I did take it to someone a while back who ran a diag on it. Several pages of codes came up. He cleared them to see which ones would came back. Some came back, but nothing related to the current problem. It's the weirdest thing.