I could really use some help here guys if anyone knows the answer.
Car is a 1991 S4 totally stock, no AC.
Two problems (related?). One she idles smoothly at 550rpm and not 900 as the book says. Secondly, has a real loss of power at midrange almost like the timing is off.
First I thought it was the VVT. On my S4, and I have checked the function of the TPS and it works like the book says, the VVT only throws for about 1 second when you press the accelerator. Checking all the wiring it is clear that the signal from the ECU that makes a ground and throws the relay for the VVT is only making a ground for 1 second so the problem is why is the ECU doing this?
Can anybody out there with an S4 verify for me that there VVT throws when they rev the engine and stays engaged? (I cannot believe it is suppose to go in for 1 second and then out). You can do this by blipping the throttle while looking thru the inspection hole on the VVT case; does yours stay "in" at higher revs?
The TPS makes no difference to the VVT even if I unplug it.
I was wondering aout the RPM/timing sensor that reads off the front ofthe crank under the water pump. Does anyone know if these things can go faulty and maybe cause my poor midrange acceleration?
Does anyone know what the ECU uses as a guide to throw the VVT. I assumed it would be the TPS (as it seems to be for the pre-1990 Spiders) but it doesnt seem to be on the 1991+ cars.
HELP!? Cannot find anyone here in the UK that understands these cars properly.
Many thanks
Britt
Car is a 1991 S4 totally stock, no AC.
Two problems (related?). One she idles smoothly at 550rpm and not 900 as the book says. Secondly, has a real loss of power at midrange almost like the timing is off.
First I thought it was the VVT. On my S4, and I have checked the function of the TPS and it works like the book says, the VVT only throws for about 1 second when you press the accelerator. Checking all the wiring it is clear that the signal from the ECU that makes a ground and throws the relay for the VVT is only making a ground for 1 second so the problem is why is the ECU doing this?
Can anybody out there with an S4 verify for me that there VVT throws when they rev the engine and stays engaged? (I cannot believe it is suppose to go in for 1 second and then out). You can do this by blipping the throttle while looking thru the inspection hole on the VVT case; does yours stay "in" at higher revs?
The TPS makes no difference to the VVT even if I unplug it.
I was wondering aout the RPM/timing sensor that reads off the front ofthe crank under the water pump. Does anyone know if these things can go faulty and maybe cause my poor midrange acceleration?
Does anyone know what the ECU uses as a guide to throw the VVT. I assumed it would be the TPS (as it seems to be for the pre-1990 Spiders) but it doesnt seem to be on the 1991+ cars.
HELP!? Cannot find anyone here in the UK that understands these cars properly.
Many thanks
Britt