Well i just got a call from the mechanic and all the problems with the new engine are almost ironed out. But one isnt when picked up the car last week i noticed the tachometer didnt work it just stayed on zero so i told him. The middle panel and speedometer are partially sun burnt so they are tough to read . He told me all the wires on the tach are hooked up and the cluster is just shot Is this possible? Also the temp for the engine he said is way off it he said he had a scanner hooked up too the engine and it was like 15 degrees off what the temp gauge said Can this happen of was it just an excuse for the engine running hot. Thanks all Ron

 

What year?

 

Oh sry its an 86 Z51 automatic

 

Hi :)

 

Is everyone stumped!

 

Ok first thing.... does the tach say 0, or does it just not turn on at all? Second thing, are all 4 backlights working? Take the plastic bezel off (carefully) and you will see 4 shiny metal covers. They cover the 4 backlights in the dash. Turn the key to "on", are any burned out?

 

Hey scorp yes all the lights are working. And the tach says 0 The main question was though can the engine temp and collant temp be wrong. Thanks scorp

 

About the temps, you will have to forgive me since I cannot remember 100%. Beleive that there are two places the car monitors engine and coolant temp, so yes some difference could be possible. Hopefully somebody who DOES remember 100% will chime in. :)

If the tach is on and says 0, then something is up. Possibly a wire is pinched somewhere between the distributor and the tach?

 

The temp sensor that operates the cluster temp gauge is on the right side of the engine. The tach will read 0 when it is not getting the pulses from the distributor or one or both cluster boards are kaput. The following is from my electronic repair manual verbatum for tach not operating properly :
Disconnect connector C2 at the Electonic Spark Timing Distributor. Plug the J-33431-10 harness connector from the I/P tester to connector C2 and ground. Set the controls to ON and 54 mph. If the Tachometer displays 900, the Tachometer is good.Check the connections at C2 to be sure they are clean and tight. If ok, see Section 6D. If the Tachometer does not display correctly, check the WHT(121) wire for an open (see schematic). If it is ok, replace the Instrument Cluster (see Section 8C).
C2 is the second wire and white from one end of the connector that plugs into the distrubutor and is the tachometer output from the distrubutor. This wire must have distributor pulses on it when the engine is running and those pulses go through the tach filter to the instrument panel through the firewall connector , C100. You may have a defective tach filter or a broken connection somewhere from the distributor to the instrument cluster. You will need to trace pulses from the C2 white wire to the tach filter, after the filter, to C100 on the engine side, then inside the car and then to the connector on the cluster.