topaz99

MIL light went on (solid orange) about 6/256 for the first time. I took it in and dealer stated it could be 1 of 2 things, the coolant temp sensor or something else (I don't recall but it was $1k to replace). He said they have no idea which one it is so i had him replace the coolant temp sensor first. I get a call that it's solved the problem and no need to do the 2nd repair and everything is fine.

Now 10 days later it goes on again and have no idea why. I checked and re-tightened the gas cap but I don't think I have filled up between the time I took in the car the first time and now.

I'm not sure but I think both instances it went on just shortly after entering the interstate and possibly turning on cruise control.

Any ideas of what this might be? I really don't want to let the shop keep doing trial and error at my expense. I don't think I should have to pay any more for this next repair which I will bring up to them.

sbarlas

Don't know if this helps : http://audidiy.blogspot.co.uk/2010/0...l-what-it.html
Basically says what you're experiencing. Could be something as simple as low coolant levels or a faulty water pump.

jagtoes

I would call the dealer and tell them they did not fix the problem and you will be bringing the car back so they can. Also talk to the service manager and tell him you do not expect to pay for the second repair. If you get a problem with him then go to the dealer GM.

sbarlas

I'd agree. Your first port of call is the dealer / service centre. Don't bother paying out of diagnostic equipment yourself.

topaz99

So i took it in and my service adviser is no longer working there, and I think he was only there a few months.

They told me it needs the thermostat replaced. So i asked about the previous repair and he state the error code was showing it was faulty and now it isn't so they did need to replace that part at the time. He said the thermostat is still sticking intermittently and they quoted $800+ to change it but he is trying to get the manager to give me a break on it. No diagnostic fee added either.

sbarlas

OUCH!!! You would expect that for a German piece of engineering they'd be able to diagnose the problem on the first time round. $800 is a lot. But you can't really mess around with not getting it repaired. Feel for you.