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Discussion Starter #1
I bought an Amazon cheapo multi meter with a tach/dwell feature so I could once and for all calibrate my Milano tach but now I'm just confused. I connected the meter to the coil as specified and compared my tach to the meter. Well, at low revs, it's pretty close. But then when revving up to what I thought was 4000 rpm (and which the Milano tach said was in that ballpark, the multimeter wouldn't go any higher than 2700 or so. So I revved it even higher and the highest the multi meter would go was just over 3000rpm, maybe 3400 for a second. I'm on a public street in LA so revving the car to redline isn't something I really wanted to do as the car is loud (ANSA rear and no mid muffler.)

Just wondering if anyone has any ideas about this? It's a basic Chinese meter so I'm learning towards a meter problem. Battery warning icon on the meter is on and I have another battery coming tomorrow so maybe it's just that simple. Anyone ever use a meter to calibrate their tach? What else could cause the meter not to read accurately?

I did adjust it a bit. I also cleaned the connections at the distributer and applied some Deoxit cleaner which seemed to make the tach work better for now. It seems fairly accurate or better than it usually is; it normally reads much too low.

Can the coil output an incorrect pulse to the tach? That would explain the low reading of tachs on these cars.
 

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But Mad North-Northwest
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Nah, the tach typically reads low because the adjustment pot degrades.

The multimeters with tach functionality that I've used have always been kinda flaky (this includes my Fluke.) I've switched to an Innova 3568 timing light that has tach functionality and it works really well. I've gotten my money's worth out of it over the years.

https://www.amazon.com/INNOVA-3568-Digital-Timing-Light/dp/B000EVYGV4
 

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Discussion Starter #3
Nah, the tach typically reads low because the adjustment pot degrades.

The multimeters with tach functionality that I've used have always been kinda flaky (this includes my Fluke.) I've switched to an Innova 3568 timing light that has tach functionality and it works really well. I've gotten my money's worth out of it over the years.

https://www.amazon.com/INNOVA-3568-Digital-Timing-Light/dp/B000EVYGV4
Thanks for the heads up on the unreliability of the multi meter for tach testing, I was wondering what was going on.

And I cleaned the adjustment pot with Deoxit which seems to have made the tach read close to where it should and consistently.

One dumb question though: Do the Milanos have a redline cut out in the ignition/ECU? Can you overrev them or are they protected? I've never hit the rev limit if it has one but usually by then, the car is screaming and not pulling anymore so I always shift.
 

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But Mad North-Northwest
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There's a fuel cutoff rev limiter in the ECU and also a spark cutoff one in the ignition box.
 
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