I know everyone is gonna say i should search the forum to check what people have said before, but i already have and everybody has different answers for the problem. I have only had this car for two months and this is the most problems i have ever had out of a car.My situation is the mystery no start problem. I took it into the dealership and they thought they fixed it but the didnt. Sometimes when im at lights the car cuts off and wont start and once before i was on the freeway and it cut off. Its starting to become really dangerous. Now the dealerships are giving me the run around saying there backed up from the holiday or they dont have the tools to fix it. If anyone has had this problem and has gotten it resolved please let me know what it was. thanks in advance.

 

Going to need more info than that to help you out buddy. Try pulling OBD codes as a start, you can go to Autozone and they will lend you the tool to pull codes for free. Second what did the dealership originally say was the problem (since it obviously wasn't the issue this will help us eliminate a variable). When it won't start we need to know what's missing...fuel or spark (more than likely not air or compression).

Might want to pm HDDP, this could be the anti-theft going wonky on you...I'm not sure exactly how it works, but I know the key is mated to the car. This may sound stupid, but it'll be a $.50 try, go ahead an replace the battery in your key.

And also, call a Mercedes dealership and talk to the service guy there and ask if they have heard of an SLK320 doing this (that's what our car is).

 

If you let the car sit, does it start up again?

If so it may be as simple as a plugged fuel filter. If the car runs lean it runs hot, and may be creating a vapour lock in the fuel delivery.

I had a Taurus that went in and out of the shp for a couple of weeks. They couldn't duplicate the problem. I'd drive it away and 3 blocks down the road it would stall out.

This was never picked up in reading the codes.

 

Just found this on another thread:

"Well, I think that we've finally solved the no start issue with my XF (knock on wood). This problem had been occurring for a couple of months and a few weeks ago the car stalled at a light and wouldn't start. In the end, a local dealer (Koons in Tysons Corner, VA) replaced the Relay Control Module. This module actually contains 4 control modules (including the fuel pump module) but is a single unit. Evidently a very easy fix in the end. You open the rectangular box next to the battery and the module is the part with the 40 amp fuse, 5 or 6 other fuses, and 4 or more connectors. You pop out this entire unit, disconnect all the connectors, pop it back in and close the box. Since I got my XF back on Monday, it's started every time and, maybe it's my imagination, but seems to be running better than ever."

 

So do u fix it urself or get it replaced?

 

I'm glad you dealer finally got it worked-out... Sorry I didn't see this post earlier...

The other posters were correct when they recommended that you try to get the DTC's (diagnostic trouble codes) from the OBDII (onboard diagnostics) or you can refer to it as, the master computer system...

If you ever have problems with the car in the future, ANYTHING... all of the data from the multitude of sensors built into the car will log specific DTC's that will almost always tell you what the problem is... Unfortunately you most always will need the assistance of the dealer because they have the computer interface that reads the codes...

I have posted all of the DTC's here on this site, so if you have problems with the dealer mis-diagnosing a problem, or not making a repair correctly, you can ask the dealer service manager to show you the DTC printout and refer back here for the proper related problem code...

Unfortunately, these cars, as most cars these days are manfactured so the only people who can work on them are the dealerships because of the related computer diagnostic equipment required by the manufacturer... This insures that the dealer keeps making $ on your repairs...

But with the Crossfire, most Chrysler dealerships do not have qualified personnel (Mercedes trained) to be able to diagnose and repair the car on the first time... Most are using the hit & miss method...

When your warranty expires, you are best to take the car to a qualified MB service department or independent MB mechanic with the StarSystem computer....

Happy holidays....

 

I've read many posts about this problem, some quite old, and it always came down to this "relay Control Module".
Maybe this should be a sticky?