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Discussion Starter #1
Is there a wire somewhere I can hook up my handheld tachometer to to see the rpm?

I want to check how the AC works at different rpm..............
 

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C2H5OH
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Sort of.
You can tap into either smaller wire at the coil, Green/Blue is power and the other 2 are the grounds/tach signal.
But your tach will read double the actual engine RPM. This is because 2 plugs are fired at once, Wasted Spark.

You're best bet would be to use a good scan tool and log. You might be able to log with one of the rental units from a parts store. But I wouldn't count on that.


What's the car, A/C, doing that you think there's a problem?
 

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Discussion Starter #3
I have a cheap scan tool.........

It's my parents 02 sedan, and it doesn't seem to cool down as fast as my 00 wagon.

Most AC tests want you to run the engine at a certaint rpm (1500 comes to mind) to take gauge measurements..............

Is the inductive pickup from a timing light strong enough to trigger a handheld tachometer?
 

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Wondering what KIND of a "handheld" you're referring to...

If you have a ZETEC with plug wires, most tacks HAVE an inductive pickup, - the issue comes with the duratec that is coil on plug.....
 

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Discussion Starter #5
Wondering what KIND of a "handheld" you're referring to...
old and older..... (one is analog, both have dwell function)
The kind you hookup to the negative post of a ignition coil or tach out of a MSD ignition.

If you have a ZETEC with plug wires, most tacks HAVE an inductive pickup, - the issue comes with the duratec that is coil on plug.....

it's a zetec. no inductive pickup (see above)
 

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C2H5OH
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Make a probe and piggy back it with the coil wire. Paperclip should work just fine, then wrap your pickup wire around it.
But like I said, it'll read double the actual RPM ... and that goes for COP setups too (duratec).
 

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Discussion Starter #7
Make a probe and piggy back it with the coil wire. Paperclip should work just fine, then wrap your pickup wire around it.
But like I said, it'll read double the actual RPM ... and that goes for COP setups too (duratec).
Actually, it will read 1/2 the rpm with a wasted spark (Zetec) or 1/4 with coil on plug..............

(meter is designed for old style distributors.......)
 
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