Yesterday i tripped a code that read "engine coolant temp circuit high input" (p0118). anyone have an idea of what this is. i thought it might be the coolant sensor but i read somewhere that that would make the gauge go crazy but its not so idk what else it could be?

 

Pretty common replacement part. You can try clearing the code to see if it comes back. Do you ever notice hard starts when the engine is warm?

 

i already cleared it and it came back again today (cleared it yesterday). I havnt really noticed anything different about the car running except that the code pops up . dont think i have any problems starting when the engine is warm but ill maek a point to cehck that next time. Am i right about it being the coolant sensor is it most likely sumthing else?

 

Yeah replace your engine coolant temp. sensor. Prices change, but last I checked it was around $12 even at the dealer. Make sure you get a new O ring and retaining clip, too. You might not notice symptoms other than the fault, but if it's bad your a/f is going to be off which could be slightly affecting your mpg and performance.

 

The ECT sensor is actually 2 sensors in one. There's 4 pins, 2 are for coolant temp input to the ECM and the other 2 are the sender for the gauge. They can fail seperatley and as stated already, it's a common item to replace.

Just a side note: I reused the plastic ECT clip on a car...........ONCE. Fortunatley the ECT shot out while I was still in the shop and not after the customer was 10 miles down the road!

 

I have a metal clip for mine - I'd ask for one of those when you replace it.

 

Are you an Audi tech? Can you verify if some older cars (A4's) have the coolant sender for the gauge screwed into the radiator? I'm pretty sure this is correct, but not 100%. In other words- don't older A4's have a 2 pin ects?

Metal clip?? Spiffy.

 

Yes I'm an Audi tech but only since '07. The temp sensors in the radiator or lower hose are for the coolant fans. You are correct about the 2 pin sensors, I'd forgotten about that. In that case, both the ECT for the ECM and a seperate one for the gauge will be on the engine, before the thermostat. As I said though, only been doing Audi's for just under three years so not 100% on certain things on pre-2000 model year, roughly. Don't see too many, we rarely get anything more than 10 years old at the dealership. The older ones did use a metal clip. Not sure if you can "retrofit" metal instead of plastic.

Just a note: I'm here to learn too, so if I'm wrong about something, I want to be corrected!

 

We love having real Audi techs around here. Hopefuly you'll stick around!