Okay,

I'm kind of new to this board, and just bought my first camaro 1991 RS Convertible 305 TBI. Well there are a few problems with it and the main one being that the Tach reads really high the guy I bought it from said that it went bad gradually. I'm wondering if anyone has any idea what it could be and where to start. I've ordered a Chilton’s manual I'm over here in Italy right now so asking local people is out of the question. Does anyone know if it's the crank position sensor? What about the cam position sensor? Is there a relay somewhere on the firewall it does "bounce" even at idle. I'm getting frustrated since no one replied to my last post, please just tell me that I'm a dumb *** and need to start by looking????????


BTW this board rocks!!!:rockon:

 

In technical terms: It's broke.

The tachs in these cars are never very accurate, and usually read high anyway, and fail in the direction of reading higher.

It's actually just the little circuit board on the back of the tach itself, which is replaceable; I don't know if you can get a new one though, I've never tried to buy one. I've just always dug up more used ones and snarfed the PCB off of one to fix mine.

 

Sweet!!!! I thank you sir, for your help does anyone have the part I need? I'm sure it would be hard to find here in Italy. What about any other Convertible owners out there?

 

Lynch,

Incidentally, the 305 TBI doesn't use a crank or cam position sensor. Ignition timing is set in the "conventional" manner by loosening and moving the distributor to set a base position. Engine RPM information is fed to the ECM from the distributor HEI switching module instead of a CKP or CPS.

If the engine is running normally and only the tach indication is incorrect, RB has your solution. If you are experiencing any misfire or timing/ignition problems, you may have an issue with the ignition primary wiring or distributor module. Lacking any salvage yards that may contain that model of vehicle, you can probably order through a US supplier or salvage yard and have the part shipped.

You could also try an email to one of our board sponsors, like ThirdGenParts.com, HawksThirdGenParts.com, or ThirdGenResource.com. The links are right on top of this page....

 

Vader,

Thank you for your info.

Lynch

 

Lynch -- Did you ever find the part you needed? Did it work?

I have the same exact problem. Anyone have new info on where to buy parts or how to fix the tach?

Thanks