pdorier

I bought my wife a beautiful 2009 SL this past summer that passed the local MD dealer's inspection with flying colors.
Things started to change this winter as, unfortunately, this car has to stay on our driveway overnight.
When temperatures reached the mid 30s or lower at night, the engine will crank up without any issue but the gearbox is stuck in P and it is impossible to engage a gear before several minutes of "warming up" the car.
Same thing with the trunk that will not open at such temps.
The local MB dealer seems clueless and I already spent $850 to no avail.
Any of you guys have experienced that? Any idea how to fix it?
Your help is much appreciated.

Ghostty

Hi there

Doesn't sound like fun! Have you started the vehicle during early morning at low temperatures? If you have a chance see if that happens during the day, lets say after work. So that way you will have an idea if it's system or ambiance related.
What i can think of is the oil level in the transmission, but if you say it had no problems during inspection... I'd check just to be sure. There is a dipstick for the transmission oil level, the only one, as much as i know in the engine compartment. But the dealer should have excluded this possibility during inspection, since you took it to the dealer (The dealers usually are mechanics with books when it comes to fixing stuff, unless they have a really experienced one).
Of course it might be a safety feature, so the gearbox will not break/damage operating with oil at cold temperatures.
Myself haven't experienced anything like that. Lets wait and see if anyone else will help with the issue.

P.S.
Another good idea would be to check the car with a Star System. Try to find a Indy shop that would be able to inspect all the systems for error codes or anything else suspicious.

About the trunk - operates with a different system, air operated, as much as i know, and are not related.

Best wishes,
Ghostty

pdorier

Very good suggestion. I will try that. Thank you!

moretech

I am no expert here but some plastic pieces in my 2003 get real stiff when cold, particularly mirror control buttons and cupholders, it may be just "sticky" plastic part in the shifter deal and really nothing else. See if it can be lubed somehow. Just a guess on my part, same for trunk. Good luck

kbob999

This may be related to the PSE pump. This is the vacuum pump that allows the door locks, trunk lock, and a bunch of other devices. Maybe it has moisture and is frozen?

Or, it could be the 'Park' lock solenoid on the shifter. This car is notorious for the breaking of a small plastic lever. A metal lever fixes the issue.

Those are my suggestions, other than hooking up to the Star system and testing for errors.

Ghostty

Exactly what i thought about, just couldn't remember the name Had to replace this even on a 2012 car (Camry, not a MB, but still). Cheap part, comparing to taking to dealer Good call, kbob999.

Ghostty

kbob999

FYI - I did the 'Park lock' repair as a preventative measure. Search for 'stuck in park' and there are plenty of posts for DIY fixes, rather than replacing the shifter which is what the dealer will do. Part on ebay is under $40. If this is the issue - get it fixed NOW before it gets really stuck in Park.

Tommyboy928

is it uphill parked ? next time park,, engage the park brake til it can hold the car without any movement,, then slip it in to park.. try next morning take out of park,, without release the park brake first.. only after..

the hole shifter is actually cheap new by the way, and easy to change..