So I have had my car back for a while and it seems to be algood until I go WOT in manual mode with traction control Off instead of spinning the wheels it just revs and feels like it bangs out of gear then have to turn car off and back on just to get it to move again, I just had car in for tune heat exchanger exhaust etc any ideas much appreciated

 

put stock tune back on car and see if the problem still exists - who is the tuner ?

 

It could be several things. Do you have any possibility to scan the tcu for codes? I would start with the most easy thing, checking the connection on the transmission so it's not leaking fluid to the tcu. When did you do a change trans fluid last time?

For a long time ago i testdrove a friends sl500 with similar problem as you describe. My memory tells me it where a bad valve body solenoid.

 

Check your transmission fluid level

 

+1 on checking fluid level and scanning for codes. Did you get a TCU tune in the end? Do you have issues in drive (S mode)?

 

Yeah make the fault occur and scan the obd you probably have a code that's not triggering check engine light but the code will be in the system until you restart the car.

I'm expecting you'll have the implausible gear ratio fault from your trans oil being too low or high. You can use basic obd 2 scanner like elm327 and torque app.

Put the stock tune on and see if it goes away if you cant pull codes, like new55 said. I've had some tunes mess up my cars rev limiter before and the car drops gears to protect itself. If your tune is the problem I reccomend eurocharged if your tuner cant fix.w

 

Haven’t noticed it in drive but I had my transmission plug changed a purple moths back as it was leaking trans fluid will check again tomorrow, nah I didn’t get a tcu I just got torque performance to do what I think is just a custom dyno tune . I have a little box I got from them to plug into obd2 and use it with OBD fusion app just haven’t set it up yet and not that confident with codes yet etc

 

Do you have the dipstick so you can check the level? Otherwise you can buy it from the dealer/ebay.

If you going to buy a scanner on the cheap i recommend icarsoft MBII. You will be able to read all codes and live data, no programming tough.

 

hey mate no I don’t have dipstick I will go to the dealer on Monday and get them to have a look as it will be faster than waiting for eBay.

 

There is a one time pin for the filler cap. Get one of those as well.

Here is how you use it

https://youtu.be/OcQPXRAmAmw

https://www.mercedesmedic.com/how-to-check-automatic-tranmission-fluid-level-in-mercedes-benz/

 

Hey was it power torque you got you tuning through? http://www.powertorquenz.com/
Any feedback on them?