tach in s13 rb20

[burninskulls0911]

i have a hks turbo timer with a tach and i found something on one of the threads on here and i put a 10k resistor from ecu pin 49 wire to pin 7 wire and then to the tach wire on the hks turbo timer and i get nothing does anyone know what i am doing wrong?

[mello88]

what happens when you wire it up properly, off the Tach pin from the ECU without any jumper wires or resistors? Look at the ECU pinout on FSM page EN-290.

Pin 49 and 59 are +12v to the ECU, dunno what pin 7 is.. But I don't know why you would want to do that with the resistor, where did you read that? Link the thread or post the info here.

[burninskulls0911]

when i wire it to the rpm signal wire (yellow w/red stripe) nothing when i wire it to the ecu pin #7 (which is the rpm signal, also yello with red stripe) nothing and when i do the 10k resistor from ecu pin 49 to 7 like this write up also nothing

Tachometer

* Find your tachometer signal wire from the dash plug. It's the blue wire with orange trace (LO) going into the white and yellow plug in the footwell.

* Coming out of pin 7 on the ECU is a yellow wire with red trace (YR). This is the tacho signal to the ECU. You could splice a wire into this but I'd advise looking in the engine bay and finding a small rounded plug on the afm branch by the passenger strut tower. It has a single wire going into it and a rubber cap on the end. The wire is yellow with blue trace (YL). This is also RPM signal. Run a wire from this plug, into the footwell and attach it to your tacho signal wire you found earlier (LO).

* Now you'll need to go grab a 10k resistor. They're about 6c from d!ck Smiths. You'll need to splice a wire into wire 49 from the ECU, run it through your resistor, and finally splice it into the tacho signal wire.



• Hey presto your tacho works!

[Carl H]

what chassis is the engine in?

[burninskulls0911]

what chassis is the engine in?

it said s13 in the title.....

and im wiring it up to a after market tach not the stock one

[burninskulls0911]

what chassis is the engine in?

i forgot to add that its a 90 so a single cam chassis sorry about that