Log in

View Full Version : Tach ECU wire, auto

Liu997
05-03-2009, 09:16 PM
I was just installing a tach on my yaris when, I realized that I didn't have the greenish blue wire on my OBD II port. I am guessing that an auto has it on a different wire. Can someone tell me which one is it?
PHXDEMON
05-03-2009, 09:44 PM
:iono: Your best bet would probably be to swap to a manual transmission so you actually utilize a tach :burnrubber:
Liu997
05-03-2009, 10:13 PM
no one knows, or have installed a tach on an auto?
CTScott
05-03-2009, 10:24 PM
Same position, but on my 09 it is beige:

http://i372.photobucket.com/albums/oo163/ctscott329/TachWire.jpg
schleppy
05-05-2009, 08:20 AM
^ I used that same wire and it works great.
Liu997
05-05-2009, 10:37 PM
What should I set the tach to, I am guessing 4 cly. But when I reved it up in neutral, it went to 7K rpm. Just thinking thats kinda odd.
mikenacarato
05-05-2009, 10:38 PM
it does on mine too. why do do you even need a tach for an auto?
Liu997
05-05-2009, 11:49 PM
idk, just like to see whats happening and or if the auto is shifting dumbly
GnomeBody
05-06-2009, 01:44 PM
lol Im driven an auto and I put in a tach too

we may not need it for shifting but its still nice to see the RPMs for what ever reason. In my last car (also an auto) it had a stock tach, At one point I started having this misfire that would only occur between 3700 & 4300 rpm. It was a dead give away when I googled 'misfire' and the said RPM range. if it wasnt for the tach I wouldnt have been able to diagnose it myself, so IMO, tachs arnt just for shiftin:thumbsup:.