i bought a tach and it is wired up the right way, i have power and it is grounded. i read that there is a grey wire with a blue stripe on it that i need to connect the green wire to. i looked all over the PCM to find this wire. i can not find it. can somebody anybody help me find this wire???

 

Its behind the gauge cluster on the connector i know. I had some bad experiences using aftermarket tachs.

 

so i have to take the dash off to find this wire then splice it with the green wire?

 

When I did mine I tapped it behind the gauge cluster. I am sure you can get the signal from the ECU side also.
1. Pull up on the upper dash to unclip it. Move it out of the way
2. Remove the 4 screws holding the cluster in, then pull the cluster out/
3. Pull out the screws holding the 2 pigtails in the dash.
4. Pull them out a little and find your wire.
I am sure someone can chime in with the wire at the ECU. I lost all my manuals and diagrams thanks to a virus.

 

that helps me a lot, cause i was looking at the PCM for the wire and couldnt find it. my neon doesnt have the stock RPM tach so my buddy got me an aftermarket one. as i said before i have everything hooked up except the green wire.

 

The wire should still be there. You could swap in one with a cluster that has a tach from the junk yard thats what I usually did.

 

ok i havent had time to connect the green wire but when i drive the tach stays at zero for maybe 5 mins then it jumps to 2000 and stays there. is it just because i havent hooked it up?

 

Maybe. If the signal wire is just floating around in could make it move. Or maybe it just sets there when there is no signal read.

 

ok, thank you!