coolant temp sending unit?

[Hef5.0weisen]

just wondering what indications anyone might have had if their coolant temp sending unit went south. Mine, well, I think it went belly up, goes from the "N", all the way to the top of the scale, in an instant, looks like indication to me. Good excuse to order some aftermarket gauges, I guess. Let me know...thanks, later

 

[CManT1914]

Stock guages are know for their inaccuracy, but if it fluctuates that quickly, check your sensor first. It's threaded into the lower plenum on the front passenger side.

 

[black945.0]

i think its located on the block next to the water pump

 

[Hef5.0weisen]

I know where it's located, and I'm pretty sure it (the sending unit) is the problem, just wondering what it looked like (indication) when anyone else's crapped out. thanks

 

[Chythar]

also check the wiring to the sensor. I had a rodent of some kind chew on the CTS wiring (the wire had bite marks), which resulted in a similar kind of reaction. I guess the rodent thought the engine was a nice warm place to sleep for the night.

A bad ECT will result in poor performance and gas mileage, but the guage in the car will rise and fall like usual. I'd verify the ECT is working properly as well. though I don't know how to check it on my GT, just my V6.

 

[DJHA90]

With an aftermarket gauge, what temp should it show after the car is warmed up?

 

[CManT1914]

Temperature should be around 190* I believe, that's what the stock t-stat is set to (192 to be specific). To test the actual sensor, check the resistance, at operating temperature the resistance should be around 3500 ohms. You'll of course need a multimeter of some sort to check this. I don't remember the cold specs, I'll look tomorrow and post if somebody needs them. The wiring harness should have a voltage supply of right around 5volts (mine was fine at 4.5/4.6 or so). Lower, and you got a short somewhere.

 

[HISSIN50]

Temperature should be around 190* I believe, that's what the stock t-stat is set to (192 to be specific). To test the actual sensor, check the resistance, at operating temperature the resistance should be around 3500 ohms. You'll of course need a multimeter of some sort to check this. I don't remember the cold specs, I'll look tomorrow and post if somebody needs them. The wiring harness should have a voltage supply of right around 5volts (mine was fine at 4.5/4.6 or so). Lower, and you got a short somewhere.

Cman, i think you are thinking of the ECT. the gauge has its own one wire sender, which simply sends a ground pulse to the guage.

new senders are relatively cheap (well on foxes anyhow), so that is worth a 'toss parts at it' swap. if not, ohm the sending wire out (if it shorts out, it will peg the gauge on max hot).

good luck.

 

[DJHA90]

Temperature should be around 190* I believe, that's what the stock t-stat is set to (192 to be specific).

Isnt that just the temperature that the t-stat opens? Is that they same temperature that they are supposed to stay at?

 

[WhiteDevil]

Temperature should be around 190* I believe, that's what the stock t-stat is set to (192 to be specific).

Well yeah thats what the stat is but the lower speed fan doesnt come on until 208 degrees and the high speed not until 224 degrees. So while driving around normally you will probably be around 210-220 degrees maybe while cruising on the freeway with air constantly going over your radiator you will be around 195-200 degrees. Remember guys the thermostat is the minimum temp of the engine will be.

Edit: This is also verified by my Autometer temp gauge and my Tweecer dataloging my ECT sensor.

 

[CManT1914]

Cman, i think you are thinking of the ECT. the gauge has its own one wire sender, which simply sends a ground pulse to the guage.

new senders are relatively cheap (well on foxes anyhow), so that is worth a 'toss parts at it' swap. if not, ohm the sending wire out (if it shorts out, it will peg the gauge on max hot).

good luck.

Crap, I've been talking too much about sensors lately, lol. Hey, not to hijack this thread, but can you take a look at my thread about my sensors? I started a new one yesterday with specs for all my sensors, and updated it today about my timing. This thing has got me stumped.