Lethalv6

This car is finally running after being left for 8 years and the gauges are jacked..I notice the sweeps are really choppy although mostly accurate but the tach reads about 4K above actual rpms. Is there a control panel I can replace or will I have to replace the whole gauge panel? (I hope not) I can't find this tach filter everyone talks about anywhere.

John in RI

iTrader: (167)

The Tach filter is normally screwed to the fire-wall & it's usually mounted somewhere behind the distributor cap. IIRC it gets it's ground from the body when screwed in place, so if it's just hangin' in the engine bay it's probably not working right. It just help to "smooth" out the RPM readings,... but if your Tach is off buy 4K you're gonna' need to either replace the Tach or have it repaired.

Remember; V6 Tach and a V8 Tach are NOT the same !

Lethalv6

Thanks John, I've looked everywhere in that engine compartment and can't locate that thing anywhere. The tach seems to have gotten worse, now at idle it sits at 5500 rpms but still moves around some.

John in RI

iTrader: (167)

Ya' Really seems like you need a replacement or repaired tach !


Here is a picture of a Tach filter. It's not unusual for someone to remove this thing after an engine swap. I've also seen several cars with the "factory" engine where someone has pulled this off. The tach will still work without it.

Go to your distributor cap then find the wire that leads away from the TACH terminal on the cap. That should be the Tach filter wire.

Lethalv6

Does anyone make replacement pieces ?

John in RI

iTrader: (167)

I don't know if anyone makes a new replacement Tach filter. It's possible that I've got one in my wiring pile.

As far as a Tach,... again; might be tough to find something new, but it's not too hard to find a used replacement. Probably going to be tougher to find a TESTED used replacement,... but there are plenty of used ones out there.