Anyone having Autometer Tach issues

[Z U L8R]

i tried the tach adapter ($75) and could never get it to work my tach, i connected the autometer tach's signal wire to the tach wire off the ecu...don't do that it'll pop the resistor in the ecu in 2 seconds. so if you're running safc2 and can't get tach signal off of the tach wire ,you can put an safc2 on either of the 120degree cam angle sensor wires that go to the ecu and it'll read rpm no problem, you can also hook up your autometer tach to the same wire and it'll read ok, BUT at high rpms the signals overlap and your tach'll read all goofy. so here's the solution

 

$30 msd part #8918 , it's about the size of your thumb from tip to knuckle, way smaller than the tach adaptor, it's half the price, and it works perfectly.

 

clip that on the white wire that powers your ignition coils, give it the ignition power, the ground, and connect the green signal wire to your signal wire for your tach, and voila.

[Pop N Wood]

Thanks for posting that.

 

Looks like it will have other applications as well.

[bryan01]

i'm not sure if this is exactly the same thing, but it's worth a shot if you're bored one weekend and want to tinker w/ a soldering gun

 

http://forums.hybridz.org/showthread.php?t=122184

 

or you can build one

 

http://www.gweeds.net/carpage2/RevCounterCircuit.pdf

 

i built the circuit above and it works great, got the parts from radioshack, first time cost is less than 10$ but subsequent ones (or other soldering projects) are less than 1/2 that.

 

if you need anymore info on this ask me, right now i'm using this to my megasquirt, but i can put as many outputs as i want on the board, so anything that needs a tach signal hooks right up.

 

i tried hooking my squirt to the angle sensor as david said, but it wasnt a strong enough signal to split between the stock ecu and the megasquirt. i didnt try hooking up a gauge to it thou.

 

edit: i'm going to call turbo dave about the exhaust and ms tuning later this week definately, i'll give you a call after i talk to him.

[streeteg]

where exactly did you get that part? I have been trying to hook up my tach for weeks!~

 

Is this it?

http://cgi.ebay.com/ebaymotors/MSD-8918-Tachometer-Signal-GMR-Pickup-Shift-Light_W0QQcmdZViewItemQQcategoryZ46101QQihZ020QQitemZ300119480029QQrdZ1QQsspagenameZWD1V#ebayphotohosting

 

 

 

edit:also, can you snap a pic of how you have it hooked up?

[Z U L8R]

that looks very similar, i'm sure it's the same thing as msd's part. i can't take a pic at the moment cause i don't have a digi cam, but you clip it onto the thick white wire that feeds the 12volts to your coil packs. the thick white wire is on a small 2 grey plug in the same harness as your coil packs, it should be right next to your ignitor. you can do it on either side of the grey plug it's all the same. once you clip it on the 12volt power supply wire to the coils, you run the green wire to your tach's signal wire, then the other two wires are just like your guage, one is 12v ignition power, the other is ground, and voila =]

[streeteg]

sweet! I already have the tach all wired up in terms of lighting up-- i just couldnt get the signal to the guage! Where exactly did you get yours again? I cant wait to get my tach workin....

[Z U L8R]

the tach signal pickup has 3 wires, mine was red,black, green, red = 12v ignition power, black = ground, green = tach signal which goes to the tach (tach's signal wire on the tach)

[streeteg]

oops... haha my wording was bad.... i meant where exactly did you get the part?

[Z U L8R]

http://www.summitracing.com

[streeteg]

purchased! Thank you for the good info!

 

-Eric