BCat

Hi guys,
So this car sat for about 4 years before I bought it. I recently got her running but the temp gauge doesn't work, it always reads full cold. I saw on a very old post that Shoebox recommended grounding out the lead to the sensor (the one in the head, not the one in the pump). He said doing so should cause the needle to read full hot when the key is on and if so the sensor needs to be replaced. Mine doesn't do this, the needle remains pegged at cold, what's my next step?

General car information:
1994 Z28 with LT1 and 6 speed stick, T tops (not sure if wiring would be different for a convertible, doubt it but figured I'd mention it just in case)

I appreciate any help

Injuneer

To save time and avoid having to type your car info every time, please add a "signature".

https://www.camaroz28.com/forums/lt1...nature-879835/

Did you access the complete Shoebox guide to temp sensor testing?

4th Gen LT1 F-body Tech Articles

In order for the gauge to remain at the cold end, it requires very high resistance. Typically that is the result of an open circuit (infinite resistance)..

BCat

Thanks, I wound up checking with a power probe, and my "ground" was not actually a ground. Rookie mistakes. After doing the test properly, it seems I do in fact need a new sensor

Injuneer

Can be either the wire or the sensor.

Key on, connector off the sensor, did you have the correct voltage between the connector on the end of the wire and a “good” ground?

When you measured the resistance between the sensor pin and a “good” ground, did you get a rational resistance based on estimated temperature of the sensor?

Unless you have done both tests, you don’t have a complete picture.

GaryDoug

Ground the wire (short to ground) and it should read full hot. Unplug the sensor (open circuit) and it should read full cold. If it does both, sensor is bad. If it does not do both, wire or connector is bad.

rlf07

In a Chinese made temperature sensor, the temperature hand came to an end in 1 minute, although the car was cold. the problem was. No connection changes or repairs, delco got stuck and everything is fine

GaryDoug

I am interested in some details about your experience. Can we try to struggle through the language barrier?
What part number was the Chinese sensor?
Do you have the base value and a temperature coefficient number?
Positive or negative coefficient type?

rlf07

I couldn't remember the temperature sensor brand and part number. but the price is one of the cheapest. (It was written in china) the event happened as follows. cold engine and first starter (50f) begins to warm up engine (60-70-80f) indicator points right here. When it goes above 80f, the display will show max after two seconds and the gauge check light will turn on.