StealthElephant

So I got in my car this morning, it was a really rainy/humid day, like 50*.

Put the key in ready position, I heard the fans turn on, the fuel pump came on, my radio came on etc. I went to start the car, and everything just cut out.

My tach went to like 5500 and sat there.

I jiggled my battery posts and when I got back in the car the interior lights worked again. So I put the key back in the ready position and everything starts working like normal, EXCEPT, my tach is now maxed out at 7000RPM.

When I shut the engine off, it drops to 6500, when I put the key into the ready position it goes to 7000.

Did my tach break? I'm really pissed....no idea what is up with that. I sorta need my tach.

92RS305#2

the connection wire is probably loose or something like that. and for future reference i'm pretty sure anything mechanical or non can break on a car given the right circumstances.

Black6SpdTA

Agreed but in this case we're dealing with 3rd gen gauges

These gauges are notorious for going out, and the stock tach is anything but accurate. I'd double check all the connections, but if even something is remotely wrong, get a new one. Good luck, btw, is the car running yet? I've been reading about your 350 problems for months.

-Corey

aklim

Check the wires at the coil. BTW, my stock gauge is as as accurate as the snap on inductive light. At least they read about the same.

StealthElephant

"When you turn the key on before starting, the tach is trying to go to 0 by the shortest route it can. You may need to remove the front part of the cluster and manually move the needle back around the lefthand side of the dial. The only other way would be to rev the snot out of your engine, and hope it revved high enough to 'catch' the axle shaft and pull it back around ."

Someone on TGO said that to me.

The first thing I checked was my tach wire connection on the coil, it's fine. The connection probably isn't loose because when the car powers up, the tach goes from 6500 to 7000 and refuses to move. As far as I know a tach is like 2 wires, power and to negative side of the coil. This engine just doesn't want me to tuen it.




I mananged to get 11MPG out of the car. I recurved my distributor and weights and I'm back down to like 8 MPG and I'm only getting 26-28* total timing @ WOT. So I'm going to pull my distrib again, readjust weights to get more timing back, then I'll readjust vacuum advance to get my fuel economy back.

It's gonna be almost impossible tho without my tach since I need to know engine RPM so I can see how much mechanical timing I'm getting and to tune the vacuum advance. Which is why I'm really pissed right now.

EDIT: Wow, that's retarded, I fixed it, took the gauge faceplates off and turned it back to 0, when I started the engine it read normally. Freaky how it managed to get itself stuck.

aklim

Get a cheapo autogauge one and connect it to the wire coming from the distributor to the tach and see if that gets bad readings too. If it does not then your problem lies in the tach.