Effects of having no Water Thermosensor?
10-05-10, 03:50 PM
#1
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Effects of having no Water Thermosensor?
Hey guys!
While battling some problems with my Turbo II, I noticed that my water thermosensor(WTS) was, and is not, connected. I also realized that it has never been connected since I purchased the car.
I know that the WTS leans out the fuel mixture once the motor reaches 120*, but I am wondering what effect an unplugged WTS will have under operating conditions.
P.S. - I have been searching all day and can not find out any more info.
Thanks!
While battling some problems with my Turbo II, I noticed that my water thermosensor(WTS) was, and is not, connected. I also realized that it has never been connected since I purchased the car.
I know that the WTS leans out the fuel mixture once the motor reaches 120*, but I am wondering what effect an unplugged WTS will have under operating conditions.
P.S. - I have been searching all day and can not find out any more info.
Thanks!
10-05-10, 04:10 PM
#3
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id have to look and see which of these cases are true. when you unplug the sensor the ECU sees this as;
-32F, the ECU will try to supply fuel for this cold of a temp, doubtful the car will even start at a "normal" 65-70F... horrible flooding
or
the ECU will think its HOT, and pull as much fuel as it can. again, it probably won't start at 65-70F, not enough fuel. if you did manage to start it, it will probably be too lean to idle...
in theory the ECU has a fail safe value in the middle (80c), but the ECU tends to just believe the sensor, so it doesn't seem like its smart enough to figure out to use the fail safe.
-32F, the ECU will try to supply fuel for this cold of a temp, doubtful the car will even start at a "normal" 65-70F... horrible flooding
or
the ECU will think its HOT, and pull as much fuel as it can. again, it probably won't start at 65-70F, not enough fuel. if you did manage to start it, it will probably be too lean to idle...
in theory the ECU has a fail safe value in the middle (80c), but the ECU tends to just believe the sensor, so it doesn't seem like its smart enough to figure out to use the fail safe.
10-05-10, 04:20 PM
#4
On my old s5 T2 I had the same situation. I replaced the connector with a good one, re-connected the sensor and voila! Instead of taking about 3 seconds of cranking to start when cold, it only took 1 second of cranking for the motor to start. Hot starts were easier too, no more flooding.
Other than that, I couldn't tell any difference as far as performance at all.
Other than that, I couldn't tell any difference as far as performance at all.
10-05-10, 05:38 PM
#5
The water thermosensor connector is a Bosch EV1 fuel injector connector with an offset tab, same as s4 BAC valve and same as 88 model fuel injector connectors. You can buy a universal injector connector and use that, as long as you file off the tab from the bottom of the sensor.
10-05-10, 05:50 PM
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or instead of filing off the tab just go to autozone,napa, schucks, or wherever you get parts and buy a new sensor since yours is most likely 20+ years old
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10-06-10, 01:11 PM
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The car runs fine when running, just the occasional starting problem when cold. Now I just have to find where that plug wondered off to.....
