Been having this issue before I put the car away for winter. Today after my winter project, I took the car out and notice that none of the above were working at ALL. Before they used to work but if I floored the car then they would go out. If I cycle the key to off and on then they come back. This whole time I was thinking my cluster was done but today I notice that the PFC isn't reading speed either. Is this still a cluster issue or do I need to look into something else?

 

Is the tach on the PFC working?

 

Is the pfc actually coming on? Mine had a bad ground and would just flash. The speedometer and dash instruments wouldnt work as well.

 

The tach in the pfc works fine.

The pfc is on steady

 

Any one else?

 

ah i need help with this too, same problem just started last friday, was driving and the speedo, tach and odo just stopped while driving but like the op my pfc still reads the rpm just no speed.

oh and the tach seems to work only if the car isnt moving and i put load on the power steering.

 

I guess I'm on my own on this one. Well let me play with some wires and see.

 

Sounds like a ground. Check the ground that connects from the harness to the firewall side of the UIM.

 

I only found one ground and it wasn't attached to anything. It is the flat strand one. I guess I have to look around and see if I find it. Can some one provided a picture of the ground?

 

Flat strand bolts to the intake mani on one side. The other side is a spade connector that connects to a male tab on the firewall.

 

I guess I should have been more specific. The ground is attached to the engine and firewall but not to a wire harness is what I ment so I don't think that one is my issue.

 

The gauge cluster measures the vehicle speed signal directly from the 2-wire magnetic sensor on the transmission, and then creates a digital signal to the stock ECU. If the gauge cluster had a problem with power or ground, it would not send the vehicle speed signal to the stock ECU.

Have you had the gauge cluster out lately? The connection between the cluster and the wiring harness isn't great: the plugs squeeze a flexible circuit board against the plastic cluster housing, it may be possible for the circuit board to move away from the plug.

 

Yes my cluster has been out all winter. I will take it out and have a look behing it and see.