on my 86 na i finally got my temp gauge to read. ,my cars warms up within a fews minutes all the way to 170 degrees celcius. or im assuming guage only goes to 150 and then red. so what is the optimal running temp for my s4 engine. thanks

 

You mean 170 defrees F. 170 C is quite hot, considering thermostat temp is 86 degrees C.

170 F is a bit cool at 76 C. Make sure your thermostat is not stuck open.

Where is your gauge sender?

 

i do mean 170 c it says c on my guage. its a aftermarket guage. and my sender is the stock sender i just replaced it with a new one. and my thermostat may be stuck hwo would be the easiest way to tell? the guage it self goes to 150 then starts red but i belive it between 160-170 c its a oil temp not coolant( i think)

 

So is this gauge hooked up to your coolant or oil?

 

If your water temp is really at 170°C(340°F) you have serious problems. Check the units on the gauge and make sure the sender is working right.

 

You can't run an aftermarket sender on a stock gauge. The gauge is matched to the sender. Your gauge isn't reading correctly.

 

its an aftermarket guage not sender... i bought a new sender for my car off the net. and the stock guage is not hooked up. but perhaps the after market guage is misreading and maybe i should see if my stock guage will read it correctly. and i belive it coolant temp since when i remove the temp sender(right beneath the pressure sender) coolant come out not oil. also the car has never smoked or cut out or anything has gone wrong due to this i just wondering if my guage may not be working correctly.

 

Is the aftermarket sender intended for the aftermarket guage? There are all sorts of senders available, but only a handful will have the correct resistance sweep for your gauge.

 

Unless the sender came with that gauge, it is mismatched. The sender and gauge are matched.

 

yea its a oem sender. ill try hookin the stock guage up to see if it reads arounf the mid range and just make shure it not over heating. (i just drove it over 400 miles nonstop with no smells or anything like that. just felt like at 80 my injectors where surging once in a while.(maybe my elimination bolt for the pd)

 

You can't use an aftermarket gauge with a stock/OEM sender.