Hello all,

I tried installing a tach into my 2005 honda civic VP. The tach is an Equus 6086, pretty standard. I can get power to the needle and lights, however, when I start my car up the needle is erratic. When I rev the car the needle won't go above 1000-1500 rpm.

I have tried hooking the green (tach signal) wire to a couple different locations on my ignition coils. Every coil produces the same erratic needle. The instructions say the negative side of the coil, but I only get somewhat of a signal for the tach-signal wire on the coil. The ground is hooked up, but I'm thinking I may need to run it into the engine compartment.

Does anyone have any thoughts as to why my tach won't properly read my engine's rpm's?

Update: the ground is good. The tach seems to be getting a reading in proportion to the engine rpm's, however, the needle still won't go above about 1500 rpm's. I've tried switching the power source to see if different amps had any effect on the needle but to no avail. Perhaps this is a defective tach?

 

The tachometer is controlled by the CPU built-in the gauge assembly. The CPU receives pulses from ECM/PCM.

There are several places to tap into the rpm output wire that comes from the ECM/PCM. Here are two areas:

- One is the Blu wire coming from pin A13 of the green 22P connector of the gauge assembly.
- Another is the Blu wire for the test tachometer connector, located in the engine compartment, near the battery.

 

Tech8, you are a tachometer god. Problem solved, problem staying solved. I used the blue wire next to the battery. Thank you so much.
-Krovski

 

Glad it worked out.

I'm not a god, just a person trying to help out. Lol.