Tachometer problem

[custom442]

your right....it's a brown wire..and it'll be found attached to a tach filter assembly on the firewall

did the monte and cutlass have different color wires??? Mine is white, there is no brown wire at all to the tach

 

[pontiacgp]

:?

 

[megaladon6]

mines also white, maybe it's a year thing?

 

[custom442]

I don't think so...ever G body I've had it was a brown wire...the drawing up above shows that it's a brown wire that goes to the distributor and I doubt that GM would have changed the wiring in any of the metric cars....yours could have been changed by a previous owner...

It was 100% stock when I got it, I think megaladon's right it must've been a different year thing

 

[Doober]

Every G-Body I've ever looked under the hood on has had a brown wire. They may have changed it to avoid confusion between the cluster harness and engine compartment.

 

[CamaroAdam73]

Just wanted to say thanks for the help and advice guys, I found the tach wire and re-wired it, turns out the tachs shot. I'm just going to pickup an after market one.

 

[Doober]

Don't toss the original tach if you haven't already, it should be repairable.

 

[CamaroAdam73]

How so? When i hook up the tach wire it just winds all the way past 7 and stays there

** and also if i don't hook the tach wire up, for some reason it will sit there and slowly climb up, even if the cars not running

 

[85 Cutlass Brougham]

If it does that, it may just be dirty contacts either in the cluster or where the cluster plugs in to the main harness. Dirty or loose contacts can make any of the gauges read all screwy. I would try removing the cluster and cleaning the contacts in the dash plugs with some fine sand paper (600 grit) first, and maybe slightly bending them out in such a way as to increase the tension with the cluster. This worked on my car. As I like to point out, there are old cars with old car issues like this that sometimes need to be addressed.

 

[Doober]

It's likely the resistor portion of the resistor/capacitor circuit is bad. I've seen this happen before myself with mine when I was trying to repair it (still haven't done it completely, but it's much closer to accurate than it was before). The resistor in effect bleeds off the charge from the capacitor, and since the resistor is not there (providing infinite resistance to the circuit that would normally have around 190-200kΩ iirc) it climbs to max.

http://www.youtube.com/watch?v=lvup_fKo6Qs