engine temperature

[fletchie55]

replacement sensor is £16 from vag parts, they will know which one it is if you tell them you need a new 4pin temp sensor that controls the gauge and sends to ECU. take about £10mins to change

[MarkB]

take about £10mins to change

If it isn't stuck!

[Blue_Thunder]

Are you sure? you aren't looking at the afterrun pump switch are you?

I was over seeing Grizz the other day and got him to point out the sensor (just below the large 'accordian' pipe). Hasn't bothered me too much as the gauge has worked perfectly since Monday. I also checked the channel 51 reading on my climate control and guessed this was the reading sent to the ECU as it was different from the gauge.

Bloody intermittent faults!

[Philws4]

Blue_Thunder
Posted: Dec 21, 2006 - 06:33 PM

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richs4 wrote:
The part numbers for the Coolant Temp Sensor can be found at the end of this thread:

http://rs246.com/index.php?name=PNphpBB ... mp;t=54533

I changed this on my car recently, the sensor was faulty (error logged in VAGCOM) but the gauge was showing the correct temp so this may not be your problem. I believe the ECU uses this sensor but the gauge must use a different one.


A word of warning, the replacement part number in the link didn't fit my 1998 S4. The sensor used on mine uses a different plug to connect it. Not sure if this applies to all pre-facelift cars.


I Have just discovered that the electrical connector/plug(part of the wiring loom) on my 2000 (X) is different and the new sensor 059 919 501 does not fit!!! any ideas???

Phil

[yorkie]

The gauge and ecu both use this sensor which on a 98 should have 4 pins

[okkim]

Thermostat is behind the water pump which also means cam belt off - ouch.

Thermostat housing isn't behind the water pump. It is next to it, and the thermostat can be changed without removing the timing belt. I have done that couple of times.

First you have to remove the coolant, then open the thermostat housing bolts. After that turn the engine carefully pulling same time the timing belt away from the left cylinder head (looking from the front). Then when the belt is about half on the cam sprocket the housing can be removed.

[Philws4]

Yes the sensor has 4 pins but the terminal end is a different shape, more of a 'D' shape than a square and has slightly smaller terminals.

To clarify i am looking at the sensor under the flexi pipe that links the MAF to the Y pipe almost directly above the O/S turbo and is situated in a black water pipe which if you follow round also has the sensor which i changed to modify the after run pump (under the expansion tank)

This is right is'nt it??

Phil

[Philws4]

Here is a link to a pic the same shape as the one i got sent out but mine is dark green in colour.


http://cgi.ebay.co.uk/TEMP-SENSOR-SQUAR ... dZViewItem

[Philws4]

After swapping sensors with Blue Thunder(Once again thank you for your speedy assistance) i have now got to the bottom of the engine temperature issues i was having with the car.
I will say though that the sensor is a PITA to thange (more so than the over-run sensor) but am pleased that i now get consistant readings from the guage and 51c on climate display.
Incidentally the readings i was getting on 51c before i changed the sensor were about 25/30 deg c out!!! and that was on a cold engine, min32 max38 deg c as apposed to a stable 10 deg c.
IMHO this is a part that should be changed on any S4 that still has the 'older black' sensor still fitted but double chech which part/terminal shape you need first as there are 2 that i know of: 059 919 501 & 059 919 501 A
Thanks for everyones help.

Phil