I have a 2000 s4 with 72000 miles with an APR 93 octane chip and have yet to replace my water pump or timing belt. I believe that my thermostat my have gone out. Both my oil temp and water temperature gauges are either bad or are not reading. Neither of the gauges works unless in the 4 or 5 minutes they read they are under demonic possession, but again this is sporadic and at random points during driving. In the next week or so I plan to take some course of action. Could the thermostat be stuck open? If so would that not cause the car to constantly run in warm up mode and cause terrible gas mileage? If so is it possible to change the thermo with out having to put the car up on a rack. All I have is jack and stands and being a poor college student that just replaced his clutch $2400 in all plus a few other things, I really don’t have much left over to pay out to a shop. I would prefer to do my work myself. Do you know of a good DIY post anywhere they would do a step by step lay out. Just a though but probably wrong. I was talking to my buddy and we thought that the fuses could of been bad, checked them an they were all good. Could there be an issue with any of the wires or other fuses for the instrument cluster up under the dash or just the instruments? The only reason I say this is that both of the gauges went out at the same time. I know that loose wires, touching wires or a bad connection or any combination of these could have caused this. If this is a possibility how could I check this? I have a digital multimeter but really would not know where to approach /start it on the car. I know how to take off the driver side knee bolster, but have no idea where I would go from there. Sorry, for all the questions. I am fairly new at this (especially with any electronic components or workings) and greatly appreciate your much needed help, any thoughts comments or advice would be greatly appreciated thank you!!! I have read that you can replace the coolant temp sensor for $5 and am planning on trying this. Where would be the best place to get one from -esc tuning has them for $20 is that fair? Do you think this could solve the whole problem?

 

are you having heating problems?? if not then your problem sounds more like a bad ground or poor connections to those sensors or the dash, I dont think the thermostat would effect the dials in that way

 

No, i am not haveing heating problems. if the problem is a bad ground or poor connections to those sensors or the dash how would i check this or attempt to fix this?
thanks chase

 

you dont just check for bad grounds you clean any you can get at, only sure way to check an electrical system is by volt drop from the battery and fuses but this can take some time ( use a multi meter at the battery ans check what voltage is being drained ) then you have to remove fuses to stop any voltage drain to eliminate your problem,

clock- radio and alarm take power all the time so these are the first to pull fuses and leave them out till you check all the others, there are special tools but expensive