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Engine 99 corolla and aftermarket tach

Discussion in 'Powertrain' started by monkey4005, Jan 29, 2006.

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    monkey4005 New Member

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    99 corolla and aftermarket tach

    i know someone with a 99 prizm wich is somewhat like the corolla and he is trying to put a tach in his car. the only problem is that he has 2 coil packs and if he only hooks it up to one then it will read half rpm. he was told by a mechanic that if he links it to both he can blow the coil packs. what can he do to put in a tach?
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    ChristianVA New Member

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    go to the connector behind the instrument cluster because the tach reading comes off the Ecu not from the coil pack.
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    monkey4005 New Member

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    we tried from the ecu and splicing into it but the tach doesnt work off of it. thanks
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    jox_rolla Guest

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    get a multimeter and put it on ac and near the coil packs there are a set of 4 wires the tach wire should be there you just have to test it on 98 corolla its purple
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    monkey4005 New Member

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    yeah and what i am saying is that from each coil is a set of four wires, u cant use those right? because u cant go off the coil it wont read right and u cant use both and splice it because you can blow them. what kind of tach will run off of the ecu?
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    monkey4005 New Member

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    bump bump

    what kind of aftermarket tach works with the ecu?
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    rainbow_star New Member

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    Try the wire behind the instrument cluster. Just look for the signal wire by trying them one by one. The signal wire is black in my 01, should be same on 98-00.
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    oppositesleeper New Member

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    nice idea rainbow but the voltage on the tach wire in the insturment cluster isnt strong enough to power a tach. You wont even get a reading on it.
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    monkey4005 New Member

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    all the tachs i have seen though will not run off of that type of signal. what model tach do you have oppositesleeper.
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    oppositesleeper New Member

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    Listen to me monkey, your friend needs to contact autometer and get a *Tach Adapter model 9117. This allows you to pull the leads from the coil packs into an adapter which converts it into a full signal that the tach can read.

    Trust me i know from first hand experience, i had the same problem at first.

    Now i do have an autometer tach so im not sure how the range goes as far as which tachs it will work with but im pretty sure it will go for any one since the signal wires are universal.

    if you have any more questions let me know.
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    oppositesleeper New Member

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    its an autometer 5' tach.
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    rainbow_star New Member

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    It's not just a *nice idea. I actually did it on my 01. It works really well.
    You aren't use the wire in the insturment to *power the tach, you just used the signal wire to get the signal. Aftermarket tach has the other wire for power.
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    oppositesleeper New Member

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    does your guage cluster have a tach stock?
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    oppositesleeper New Member

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    it does make sense but since the car uses the dual coil packs and not the direct port ignition like stars does you have to use the tach adapter.... im telling you, if you want to tear apart you dash and try the lead then you'll learn it wont work, because that was the first thing i tried when i got my tach.
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    monkey4005 New Member

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    mine doesnt and nor does his because he showed me a pic of it. all he uses is the signal from behind the gauges to run it wich makes sence because if that is enough to signal a regular tach then why cant it signal an aftermarket one.
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    baymoe New Member

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    Use the black wire from the gauge cluster. Forget tapping from the engine bay.
    Remove black housing from around the gauges. (I have a VE and do not have tilt steering and was still able to remove it.) Remove bolts that hold the gauges and looking towards the front of the car, it's the second harness. There's a black wire. If you follow the lead back to the circuit on the gauges, you'll see that the black wire is not used. That's the wire you want to tap onto.
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    ChristianVA New Member

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    pretty much what i said on the first post. your probably just doing doing it wrong man. I run a very expesive pivot tach and it works fine.
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    Toby New Member

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    Correct. Connecter number 3 (C3) 3rd wire is solid black. It goes to your VSS, make sure you disconnect the battery before soldering or connecting. My car and another I've done both threw a P0500 code for vehicle sensor malfunction. After resetting it learned it's new load and I've not had a problem since.
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    CadetLee Guest

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    My '98 had a tach running off of the cluster signal wire..worked fine.

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