eti engineer JAN 23, 09:26 AM
I had posted earlier about my tach reading around three times higher than what my actual rpms are. I have been busy with the exhaust issue, but now that that is done, I would like to get the tach working.

Someone had suggested that maybe it needed to be calibrated, but in the meantime a new problem has cropped up. It still reads about three times what it should but then it intermittently pegs out regardless of my engine rpms. It doesn't do it while the car is idling, but when I am moving down the road it does. What should my next step be to get this cured?

Thanks in advance...
J Gunsett JAN 23, 10:44 AM
You have a PM.
theogre JAN 23, 10:49 AM
Pegging the tach is different then reading high...

reading high often means board has problems w/ bad caps and/or resistors.

peg temp etc gauges means sender section of circuit is open.
but tach and speedo "meter" is driven by a chip. The chip itself or "meter" have problems. Could be loose "meter" connection to anything.

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fierosound JAN 23, 11:54 AM
New circuit boards

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phonedawgz JAN 24, 09:53 PM
My replacement adjustable tachometer board, with options to include a precision calibration circuit and a low fuel light.