awhile doing the s4 NA>s5 TII conversion. We Installed the Microtech LT8 flawlessly. But with the LT8, you lose the function of the stock Water Temp readings. The good thing Is (s4 that Is) that you are able to regain It back should you fillet the stock Harness open to fish It out and plug It In to It's respective spots ie. Coolant Temp Sender Unit (the one under the Oil Filler Neck) leading to the Gold Harness Plug (found at the Passengerside right kick panel).

So I wired It like so but noticed the stock Water Gauge readings to go no higher than millimeters above C. Are the s4 & s5 Coolant Sender Units different In terms of output value? I know the s4 Sensor will not accept the s5 TII block on account of the pitch thread being different. Even though I have the Hand Controller and my Greddy Water Temp Gauge to give me my respective readings, I'm a bit particular on the stocker doing It's job. Any Input would be appreciated.

*Side Note* As for the LT8 Install - You lose the Water temp function, as mentioned, Cruise Control, Front Wipers aswell as the Harness Plug to the Alternator. All these could be retrieved with your favourite X-Acto knife.

 

Whether its the series four or the series five sender unit......if put in 80degree C water, the resistance should be 57.7 to 49.3 ohms. See the manual, under METERS, for what the gauge itself should look like at different resistances.

 

I did search for any variances b'n series but I'll check It again. Thanks for the reply.

 

I'm still having the problem. The readings show a consistant millimetres above the C.

I want to retrofit my s4 Coolant Temp Sender Unit using a bung.

*What Is the pitch thread for the s5 Water Temp Sender Unit?*

 

Would it work if you got an S5 guage cluster?

 

At the expense of the s5 Coolant Temp Sender Unit? Not practical. I replaced my Main Front Engine Harness with a brand new one and I don't see myself doing this again.

Unless someone can come through, I'll have to take the s5 sensor out to check the pitch thread.

 

You could've just run another wire and splice into the yellow wire in the kickpanel.



-Ted

 

I followed the same route my LT8 Harness Loom followed...the only difference Is I extended It by a good 3ft. I didn't want to have loose wires all over the place. Fortunately for s5 owners, they don't have to go through the same havoc us s4 owners have to through when doing this practice considering their Water Temp wire runs at the opposite Harness.