VR6 Engine Temps

[The_Hawk]

It looks like I *may* have found the cause of my thermo fan issues. Although I have been told the fan speed is run off the sensor in the radiator not the other one...



While driving on the freeway today my temps were maybe 70C with the AC on and the high speed fans on.

AC off and high speed fans off and it slimbed to 75~80C.

Interesting that with the AC/thermo fan plug unplugged it was running right on 90C where it should be.

Looks like it is time to swap out the temperature sensor and see what happens.


I'm hopiing it's the sensor since thats going to be a hell of a lot cheaper/easier than replacing the thermostat itself.

Considering it was working OK not long ago I'm hoping for the temp sensor.

Anyone have any ideas?

[The_Hawk]

While I'm thinking about it...

Is it the plug on the right here?
Located front right of the engine.


Yeah the one with the dodgy looking wiring...

Is it as simple as pulling that green clip thing and sliding in a new one?

It can't be that easy can it?

[Jmac]

As simple as that pal but renew the seal too. Even easier with a cool engine mate. Dont know how many times ive done one with the customer waiting with a hot engine!!! Had my wrist burnt a few times in there

[The_Hawk]

According to Bently's:

The three plugs from left to right are:

1. After-run coolant fan control thermal switch (F87) and ECT sensor (G2).
2. Engine Cooland Temperature (ECT) sensor (G62).
3. A/C Cutout thermal switch (F163) and third speed coolant fan control thermal switch (F165)

1. Should control the thermo fans and the thermostat after the engine is stopped (or while it's on).
2. Sends the temp to the guage / ECU.
3. Should work with the AC to turn on the thermo fans when the AC is on.

Now since the guage seems to read right sensor 2 should be right.

But the fans run all the time and stay on after the car is stopped for a few minutes. I have had a hard switch put in to stop the high speed part running whenever the ignition is on... So sensor 3 may be buggered...

I wonder do you think I can swap out 3 while at the parts shop to see if that solves the problem? Then get sensor 1 and try that is all else fails... then cry if it doesn't...



A wonder what this one is going to cost me...

Anywhere besides Moorebank to get a new sensors?

I wonder if Golf Loon has these sensors in that VR6 he's parting out so I can swap them out without driving to Liverpool...


I have been reading other posts about overheating/too cold issues and it was suggest to check for error codes. Wolfsburg run the VAG-COM box over the car and didn't notice any error codes a couple of weeks ago.

Tomorrow is going to be fun.

[Golf Loon]

I reckon the previous owner would have tried all the sensors.

I`d have them all though. I have a complete VR6 out the back for parts.

THe only spanner in the works can be the engine lifting bracket fouling the clips that hold in the sensors.

[The_Hawk]

I reckon the previous owner would have tried all the sensors.

I`d have them all though. I have a complete VR6 out the back for parts.

THe only spanner in the works can be the engine lifting bracket fouling the clips that hold in the sensors.

Couldn't we just plug in the sensors without putting them in place, so technically they would be reading ambient...

Shouldn't that see if it they were working or not?

Also wouldn't they then read a low temp and so close the thermostat, so the pipes shouldn't heat up.... which also means you could tell if they thermostat were stuck open or not...

Just ideas, reckon they would work?

[pommy_golfer]

I bought all these sensors new from Tooleys and they cost about $20 odd dollars each. Replacing them is a doddle (providing the lifiting backet is not thereas )...i still managed to change them witht the liftingbacket in place though, but a bit trickey!

From my experience, i would go and buy these sensors new. these thinga have been there for the lifetime of the car, and another sensor from another Vr6 is still old and you have no idea if they actually work or not.

Someone mentioned before that Bosche recommends their sensors be changed every 10 years, so its overdue probably!

[The_Hawk]

A few $$ and third degree burns later I have a new(er) sensor in place. Yes it's not a brand new one, but it works and saved a trip to Moorebank, that and I'm sure McGrath parts would make that sensor more like $100...
Once again, thanks to Golf Loon for having just about EVERY part known to the VW gods lying around his workshop.

Yes the lifting bracket is in place so it was a little bit of a challenge, but now it's done so I'm happy.

I also have the missing piece of side moulding I needed, although it needs to be painted up since it's green and all.

The car now heats up to and runs bang on 90 again and after a good thrashing to bring the temps up the thermo's are coming on when they are supposed to. YAY!

HINT: When your told it's better to work on a cold engine, cold DOES NOT mean "when you can touch the manifold for more than 2 seconds without screaming..."

Amazing how hot 80 degree is