I just did a search for this but nothing helpful came up. i noticed that when i go WOT my tach seems to hesitate for a sec then speed up to were it should be. Example: say i'm at 3500 rpms, while accelerating, it'll stay there for maybe a half sec then jump to, say 3750, or 4000, where it would be if it were moving steady. But this only happens when i floor it, my friend told me it could be the cable, but i just wanted to make sure.

 

The tach is driven off of the distributor pick up, not a cable. Sounds like your guage is worn out but cant be positive. I would just get me a nice AutoMeter.

 

U see my dumb friends are the main reason why i come to this site

 

I only listen to friends that have really worked 5.0s. Not plans to work their 5.0s or if they dont even have a mustang in the first place, lol.

 

I dont wanna steal the post, but i have a similar problem. I have my autometer shift light set at 5800 rpms, but when my shift light lights up, my tach (the stock one) says im at 6200 rpms.... Whas up wit that? I dont really care about te stock tach cas im pretty positive the shift light is right, but i was just wondering.

 

none of the stock gauges are really accurate.

 

yea, my mustang book says the stock tach reads high.

 

I always knew it was a little off, but 400 rpms is a lil more than just a little. It only started reading that bad when i added my b cam, but im not complaining, i love my bcam.

 

stock gauges suck. autometer owns all.