Hi Guys

I have a shift light that only works with a ecu tacho signal, not a coil negative. Would anyone know where that is? or what pin on the ecu i should tap into?


Cheers guys

 

What ecu do you have?
If it's a Weber L8 you can get a signal off pin 7 on the ign. amp module.
If it's P8 some versions had a tach output off pin 7 or possibly pin 9 but i'm not 100% certain as within the same ecus the pins drove different things on different vehicles.

 

Sorry i should have said, it is indeed a L8, so hook into pin 7? ill give that a shot tonight and let you know how i get on.

Cheers

 

on another side while we talking about tachos.

my L8 loom (feeding a p8) has a tacho filter thingy. Can you get new ones when making a new loom? or can you get away with ditching it??

 

www.bigturbo.co.uk

 

none of those wiring diagrams show a tacho feed.

 

Yes, seeing as it's an L8 set-up connect the tach. wire directly onto pin 7 of the ign. amp, i did it on my non cos. turbo 16v twin cam 2.0 engine and it workes perfectly with the stock car ins. cluster's rev counter.
I wouldn't be too sure that it'd generate a proper signal for the shift light seeing as the amp. is also connected to the coil, try it out anyhow.
Let me know if it goes ok.

 

Warren, does the tacho actually work? or does the needle bounce about at idle?

 

my tacho works fine.