RS EJ20G to L series, tacho

AndrewT · Post by **AndrewT** » Sun Apr 16, 2006 12:44 pm

MPFI L series Tourer, EJ20G with standard RS ECU.... how do I make the tacho work?

Suba · Post by **Suba** » Sun Apr 16, 2006 3:02 pm

have the engine running

Mike.

Craigus · Post by **Craigus** » Sun Apr 16, 2006 6:13 pm

The ECU has an output to drive the tacho; not sure if it will drive an older style tacho directly or not.

The tacho output is C16 on this ECU:

http://members.optusnet.com.au/atar/EJ20G_ECU.pdf

Not certain if yours is the same pinout though.

tim_81coupe · Post by **tim_81coupe** » Sun Apr 16, 2006 7:38 pm

Should be a black wire with a blue trace from memory.

AndrewT · Post by **AndrewT** » Sun Apr 16, 2006 11:24 pm

Sorry shoulda provided a little more info....

I have the wire from the RS ECU marked already, just wanted to know if there was anything strange required for hooking it up to the tacho in the car. (a similar conversion I helped on a while ago we never got the tacho to work).

Although aparently all I have to do it just hook it up to either the tacho wire from behind the gauge or the corresponding wire from my MPFI ECU plugs. My MPFI ECU pinout diagram doesn't actually list the tacho wire so it looks like I'm gonna have to pull my instrument panel to bits and find the wire.

--Tim - spot on the money by the way!
--Suba - engine is running, reving and idling beautifully

Oversteer · Post by **Oversteer** » Mon Apr 17, 2006 12:14 am

...the diagram either list the wire, or you`ll have to run the wire from the old coil plugs.... it work whatever way it was done !

...I coulda been wrong about the old ECU having said wire as the MPFI L isn`t really fuel and spark control like DFI...

OS

Ben · Post by **Ben** » Mon May 01, 2006 6:30 pm

The ECU Tach output on the EJ hooks straight into the wire going into the L gauge cluster without anything weird to do.