i have a 99 (pre facelift) a4 that threw up a code.. p0116, which means coolant temp sensor i believe. also the coolant temp guage has been out for awhile. so i found this sensor at ecstuning, but im not sure which one to get? there is a square connector and a round-type connector, both say they are for 1999. says something about vin numbers, but that didnt make sense (my vin isnt close to either of the numbers there). so does anyone know which one is for my car?

 

Since its pre facelift its probably the blue one. Look to see if you have black ECT, if so then the green one is the replacement. The ECT cost about the same at a stealership, why don't you give them the VIN # just to make sure you get the right part.

 

191 959 481 C
059 919 501 A

one is for the ECT and the other is the fan switch. i forgot which one is which but one of them is the green top ECT. it's 7 bux at autozone.