First start of engine

[Doubledip]

yep out of the GM ECU's the signal is only very weak and needs to be boosted up.. Good job on the Build

just run a pull-up resistor and all will be good.. same as what was needed for T.L's car

[Pecal]

I tried a pullup resistor suggested by Sideshow without success. I went to Howards and he said the signal used for the Tacho on these engines is Multiplex so it can't be adapted to the tacho. His suggestion was to cut an injector wire and put a signal amplifier in series to get a trigger for the Tacho - not a very attractive solution.

Peter

[Doubledip]

Originally Posted by Pecal

I tried a pullup resistor suggested by Sideshow without success. I went to Howards and he said the signal used for the Tacho on these engines is Multiplex so it can't be adapted to the tacho. His suggestion was to cut an injector wire and put a signal amplifier in series to get a trigger for the Tacho - not a very attractive solution.

Peter

No. sorry to say but he is wrong if he is saying you cant get a tacho to work off these ECU's.... maybe some tachos (i am yet to see) but it will work 99% of the time.. the other times you need a different booster..

I gather you being the Peter that we supplied the LS3 for ? ... if so i will have a look at you tune to see if it was set correctly..

Did you get any drawings on how to wire it in..?

[gjkrv8]

Hi Peter,

If you need me to come over to put an Oscilliscope on the signal to see what it looks like - let me know.

Rgds

Gregg