Car is ´94 z28. Thermometer and fuel gauge don´t go to zero when turn off the ignition. When engine is cooled down and I turn ignition key on thermometer goes down to zero. Should both of these meters go down to zero when ignition key is off mode? And thermometer shows only 1/4 temperature I think before it went to half. Otherwise the car runs well and does not leak coolant. What temperature do those lines on meter correspond?

 

”Thermometer” (coolant temperature gauge) bottom line 160°F as marked, 1/4 mark = ~185°F, center mark = ~210°F, 3/4 mark = ~235°F, top line 260°F as marked. Being in Finland, do you have an export model with a metric dash, or a U.S. model?

Can't remember what the gauges do when the ignition is off. Sold the car a while back.

 

My car is us model miles and fahrenheit

 

I found a picture of my 94 Formula dash, with the ignition off. The fuel gauge was at 1/2, and the coolant temp gauge was at the lowest possible reading (160°F). The Firebird dash layout is different than the Camaro, but the electronics are the same. And the dash in my Formula was basically the only “stock”, unmolested item. Most everything else is aftermarket.

https://www.camaroz28.com/g/picture/8152781

The aftermarket top of dash mounted tachometer appears to show 2,000 RPM, but it's a “floating” gauge that can read anything when the ignition is off. The electronic fuel pressure gauge at left side of the center cluster is also a “floater” and can indicate anything when the ignition is off.

It's a 1/4-mile track car, not a daily driver.

 

"Should both of these meters go down to zero when ignition key is off mode?"

No, the gauges are positioned with power on. When powered off, they remain before power went off. No return springs in the gauges. Aircraft engine gauges have long used this effective and simple memory technique.