Hi
I have been having some troubles with my 2006 Automatic.



It started a while ago with the engine not starting properly and me having to crank for quite some time before anything happened.
I exchanged the crankshaft sensor (for Bosch 0261210170 – equivalent to 0031532728) which didn’t do the trick. I then changed the Camshaft sensor (for Bosch 0232103114 – equivalent to 0041536928). That didn’t do it either. I re-soldiered the Relay control unit – didn’t help – still had to crack for a good while before it started. Then, after some fault-finding and reading, I decided to change the fuel filter – from a non-branded to one to Bosch. It did the trick – the car start every time now at first try. My guess is that the valve in the filter gave up.



However, I now noticed a new problem.



If I put my foot down all the way down the tranny does not shift up unless I let go of the gas. It will come to around 4300-4400 revs and stay there and the car stays at whatever speed I am going. Unfortunately this happens at any speed (and gear). If I take the foot off the gas it upshifts as normal at that point.
If I am driving normally and decide to speed up it shifts down one step as it should but then it hits the magic 4400 and sticks in that gear unless I let go a bit.
When I use the “manual” it all works fine and upshifts as and when I decide but still does not seem to go above 4300-4400 revs.

I guess my questions are:
Any idea what this could be?
Is it related to the sensors I exchanged and if yes then which one?

The thinking here is that these are for a SLK320 but not necessarily for a crossfire but I struggle to see how it would affect it.

Thanks for any help.