black_z

iTrader: (4)

I just installed a fresh LS1, and now my tach is not working. The car starts and runs well, but the tach sits right on the needle below 0 RPM and does not move. All other gauges work, except the speedo is pegged to the far right. Oil PSI, fuel, water temp, and voltage are all reading correctly. It should be noted that i completely demolished the #7 piston, could that have damaged the cam sensor? The car runs and starts perfectly. I am thinking it may be a cluster issue, even though I have never had the cluster out or apart. Thanks.

ak95ta

iTrader: (3)

What year is your car? Is the fuel level gauge working?

nemss1

if the fuel level gauge isnt working, has to do with serial data link

black_z

iTrader: (4)

Fuel level gauge is working. I wonder if just one of the contacts is bad on the cmp sensor.

black_z

iTrader: (4)

TTT, both the tach and speedo move just a hair when the key is turned on. But they do not move after the engine is running.

nemss1

ya the gauges will move a lil just because they are getting power but no serial data signal. happened to me because my serial data wire was cut somehow

ak95ta

iTrader: (3)

Well, the speedometer doesn't use the serial data signal, it recieves from the vss output of the ecm. That is what has me puzzled. Seems like the cluster may have a problem.

nemss1

oh ya, duh. i missed the word speedometer in the post. just now realized also said fuel gauge does work. my head is going 100mph today

black_z

iTrader: (4)

I will have to inspect everything when I pull it apart to install a TA bezel. The car lost the piston at about 100 MPH and killed the engine immediately, the speedo fell all the way to the right when it happened.