My tach is off about 400rpm... Why? already checked the wiring - good. Checked the contact in back of the dash - good. Checked the electrical circuit going to the tach - good....

running out of problems and I don't get why it's doing it.... put in another tach from the junkyard and it does the same thing....

anyone help? I really don't want an aftermarket tach on the side as I do run this at the track.....

someone please help....

Thanks
Chris

 

Our gauges are notoriously incorrect--that may be the long and short of it.

JamesC

 

ok.... see, i post questions on here like everyone else looking for answers.... not excuses that "our gauges are known for being off"... well thats just great!!! woopie... now, to anyone else that wants to post, how do i fix this problem or what can i do to figure out what this problem is. Tach was working just fine 2 weeks ago!

thank you to anyone else that is willing to help

 

Good luck.

JamesC

 

he was not joking, our gauges DO very GREATLY, only thing i can POSSIBLE think of, is if your dash was replaced once, if thet used the correct tach for the correct motor, because the tachs have a different resistance between the I4, V6 and V8 if i remember correctly.

 

Our tachs and other gauges are off, no joking, replace w/an aftermarket tach, (autometer,etc.) if you want accuracy. Mine was off by 400 on the bottom and almost 1,000 on the top. ??? Tried replacing, wiring, etc. The factory gauges just plain are of poor design/and or quality.....

 

original dash piece yes, however would it shouldn't change any between a 305 and a 350 though... oh well, i guess i'm going out to get an aftermarket tach... i hate mounting tach's to the side of the dash! looks like a honda then... LOL

thanks everybody for the help...

JamesC - I apologize for my comment, I re-read what I wrote and it kinda sounded like I was a jacka$$ so I'm sorry for it sounding that way. I was just wanting it fixed so I didn't have to do the aftermarket tach thing.... forgive me?

Chris

 

Good move, at least you'll know what rpm you are turning, accurately...

 

Hey, it could be worse. My tach pegs at anything above an idle, my fuel gauge fluctuates when it is between 1/4 and 3/4 and my temp guage slams to the top, sometimes getting stuck whenever I put the key in start.