ggibson

I had a post a few weeks ago on my fuel mileage going down and my car flooding.The response was more or less cold temps and short trips, car always in rich mode. This made since but the car never felt right. I was looking on the S4 forum on found a post on the coolant temp sensor that listed all the problems I was having. I went and bought the parts 059-919-501-A (sensor) and N-903-168-02 (seal) 5 min. to install and $6.19 in parts and the car is a new car again. Must have been in rich mode all the time.

Kris Hansen

Was your guage acting odd?

AndrewWK

I've been having some seriously crappy gas mileage problems myself.


thanks,

Andrew

ggibson

No. But it is a four wire conection so it must have multable functions.

Kris Hansen

Yes, the sensor is a 2 part sensor I believe, which is why 1/2 of it can be fine, and 1/2 can be bad

ggibson

S4biturbo.com under Coolant sensor failure sysmptoms by slverbullets4 Its a good page for info.

por911

ggibson, if the outside temp drops and or your state is using a petrol additive like MTBE, then your mileage will go down some. You did not post year or mileage of your car , but the state of tune of your car matters as well. You may want to check the condition of your o2 sensors. Usually, as they go bad , the sensors send a signal that makes the inj go rich instead of lean.

ggibson

I dont dought the mileage will drop off in the winter but this was 3-4 mpg. I did pop a few temp codes. The car didnt seem right. I thought it was in my head. After replaceing the temp sensor it run a whole lot better. Amazing what you get use to. I am in Michigan and the car is a 01 2.7t

QCRAZY

Interesting! What had your mileage dropped too?? You have a 2.7T I take it??

ggibson

Yes 2.7T from 23 to 19 mpg