[taxman33]

Welcome mate, see, these cars are really fine to own if you have help, if not you are at the mercy of the dealer, and that REALLY sucks. Most of the time they create more problems as well.

I'm at the mercy of a dealer right now. Perhaps you could help by answering a quick question. I had my 2018 570s in the shop for a weird transmission error message. They said nothing was wrong, couldn't replicate the issue, etc. However told to replace my thermostats... specifically "REPLACE THERMOSTATS - TECH RECOMMENDS REPLACING THE THERMOSTATS DUE TO ACTIVE FAULTS FOUND IN THE ECM" which I paid them to do. I get the car back and it throws a CEL in five min. I send it back and they said "099 REPLACE ENGINE COOLANT TEMPERATURE SENSOR CUSTOMER STATES A CHECK ENGINE LIGHT IS ON" Long story short, I talk to the service advisor and explain that this feels like they just guessed at the code and threw thermostats at it, but then now they realize it's the engine coolant sensor. He's trying to tell me that the thermostats have a sensor in them too sensing how much it's supposed to open etc. Sounds to me like BS and I'd like to know: a) do the thermostats have sensors in them like he's saying? b) what's my argument to prove that they overcharged me and should at least fix the sensor gratis?

**edit
I realize this is the wrong forum. Sorry.

 

[taxman33]

correct,thermostats have a sensor built in.

Thanks for the response. It feels mighty coincidental that the engine coolant sensor went bad five minutes after they fixed the thermostats. I'm lost as to how to argue this, though it makes perfect sense to me.

 

[taxman33]

they do not. Those are heater elements. They are used to bringup temp faster. They are not reaponsible for water temp readings.

there are 3 sensors responsible. One on each main water pipe, and one in the cylinder head for head temp.

Can you post your exact symptoms and error codes pls thanks

note that if the water pump seal has failed, you will get gearbox and clutch overheat messages and all kinds of things pop up related to temperature

Just to follow up and I'll refrain from further comment after this so as to not further derail the thread...

I spoke with Sean from McMedics and he gave me some good guidance and the dealership agreed to eat the cost of the new engine coolant sensor.

This thing started as a transmission fault. It went into limp mode so I sent it to the dealer. The dealer couldn't replicate the issue, but noticed some fault codes in the ecm related to the coolant temp. They decided the thermostats needed to be replaced, charged me the $3,600 for the work and brought the car back to me. FIrst time I drove it, I get a CEL. I send it back and they say now it's the engine coolant sensor. At that point I ascertained that they were just throwing parts at this instead of diagnosing and decided to look around the interwebz for some guidance. Sean pointed out to me that when the ECS starts to go bad, it can frequently cause shifting issues. Using that logic, I argued with the dealer that the ECS should have been replaced before the thermostats. The dealer agreed and is covering the cost.

 

[taxman33]

Very good, would be surprised if your engine coolant sensor has actually failed though. Rare, will also not cause shifting issues, if it does, its something else causing it.

Just what the guy said. Dealership agreed though for some reason. If that's not the case, then they were recommending to replace the ECS for no reason, which means I'll continue to have an issue.

 

[taxman33]

has the water pump been tested? Its easy to do.

I honestly don't know what they did. I sent it in because of the transmission limp issue and they came back with faults in the ecm for thermostats/engine coolant sensor. It's my intention to get rid of it at this point and go a different route. If it has another issue, it won't go back to the dealer for sure.