Tach Signal--Which wire or pin?
#1
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Guys, I'm trying to figure out which wire to tap into to get the tach signal for my G2X. Attached are pictures of the 3 boxes under the driver's seat, as well as the plug that goes into the back of the tach. As a reminder, this is a 1992 Turbo 911 with CIS and EZ69 ignition (pre-motronic).
Can any of you tell me which wire or pin is the tach wire?
Thanks.
Lee
Can any of you tell me which wire or pin is the tach wire?
Thanks.
Lee
#2
Burning Brakes
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Looks like your "ECU" has been moved so I have a little bit of a problem with references.
But the "box" you are looking for is not on the picture.
There is a third one, it's a contact for 6-10 pins (don't remember), it's a lid on it.
When looking into the car from the drivers side door, it's the closest box, I think the black boxes on your picture connects to this one.
On my car it was the black wire with a green stripe, I used a dwell meter to check that it was the right one.
But the "box" you are looking for is not on the picture.
There is a third one, it's a contact for 6-10 pins (don't remember), it's a lid on it.
When looking into the car from the drivers side door, it's the closest box, I think the black boxes on your picture connects to this one.
On my car it was the black wire with a green stripe, I used a dwell meter to check that it was the right one.
#3
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Okay, thanks. There's another box under the passenger seat, maybe that's the one.
I'll check it out, and if I still can't figure it out will post a picture of it.
As to orientation, I'm looking in from the driver's door (Left Hand Drive). The box labelled Jetronic is toward the rear of the car, the other two boxes toward the front.
What are these boxes anyway? I've looked in Stefan's Book, but can't find that level of detail on the turbo. The regular 964's have a lot of this kind of info.
I'll check it out, and if I still can't figure it out will post a picture of it.
As to orientation, I'm looking in from the driver's door (Left Hand Drive). The box labelled Jetronic is toward the rear of the car, the other two boxes toward the front.
What are these boxes anyway? I've looked in Stefan's Book, but can't find that level of detail on the turbo. The regular 964's have a lot of this kind of info.
#5
Burning Brakes
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I am pretty sure you had the Jetronic boxed moved, it should be at the front if I remember correctly, probably moved when installing the 6-point harness. The boxes controls fuel pump relay, heating of o2 sensor, "regulates" mixture depending on a couple of throttle angles etc. One of them are called "Turbo Control Unit" don't remember the other one.
Just checked, your Jetronic box is moved and the connector box has 6 pins.
Just checked, your Jetronic box is moved and the connector box has 6 pins.
#7
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Originally Posted by nathanUK '81 930 G50
Be careful doing this, Miles messed up his car doing this, he now has ditched all the Porsche stuff and is going EFI with a Megasquirt.
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#9
Burning Brakes
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Well ![Smilie](https://rennlist.com/forums/images/smilies/smile.gif)
I tried to get a signal from the coil (which is the signal from the EZ), however I dont know if that blew the EZ69 or not. I have had trouble with it before when I bought the car.
Thats why I spent the money on going EFI instead to run it and also I wont have any black box ignition to blow up anymore!
But I havent driven the turbo since October
![Smilie](https://rennlist.com/forums/images/smilies/smile.gif)
I tried to get a signal from the coil (which is the signal from the EZ), however I dont know if that blew the EZ69 or not. I have had trouble with it before when I bought the car.
Thats why I spent the money on going EFI instead to run it and also I wont have any black box ignition to blow up anymore!
But I havent driven the turbo since October
![Frown](https://rennlist.com/forums/images/smilies/frown.gif)
#10
Three Wheelin'
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Slightly off topic, but sometimes my tacho goes dead. It only happened since my new HID headlamps were fitted, and swicthed on. Then when I stop, turn off ignition, and restart, the tacho works again. Any ideas what could be going on?