For those with Autometer tachs......

[FO94302GTRD]

Ok, so I had an Autometer 3 3/4 inch tach mounted in my car a few days ago because the stock tach is not accurate, and actually binds past 2500 RPM. I though my stock tach was binding due to a previous owners poor white-face gauge install, but now I'm not sure. When accelerating, my Autometer tach seems to really slow down past 2500 RPM when in gear, even when I really get on the throttle. The tach was wired to the coil, so both the stock and aftermarket tachs still work.

Can a tach signal strengh weaken over time? I've heard of tach drivers, but those are advertised as being for 99 and up Mustangs, I have a '94.

Any ideas?

Thanks.

 

[95cobraguy]

very strange indeed, does the car feel like it slows down also or just the tach is falling out?

 

[91LX_5L]

yeah that is strange. mabye it is your car though!?

 

[FO94302GTRD]

Well, the car is not physically slowing down, just the tach needle. The stock tach needle won't go past 3000 RPM, even if I floor it while in neutral. And if it makes it that far, it'll stick till I drop the car back to idle. The autometer needle just seems to really take it's time climbing up past 2500 RPM. I have no clue what's going on, or maybe it's not the car and I'm just crazy. LOL

 

[HISSIN50]

If the car and tach are both crapping out at higher revs, the TFI might not be getting the coil the negative (trigger) signal to fire at higher RPM's. This can be a sign of a failing TFI (in no way am I saying the TFI is failing - not enough info is provided, nor with enough specifics).

I would dump the codes to see if something pops up.
My two cents.
Good luck.