I recently had the car in the shop for a front end alignment. The mechanic told me that the tach was off. I sort of agree with him becuse at idle it's reading like 1100 or 1200 but the engine is definitely not idling that high. I have an MSD 6 al installed (the car came with it... I didn't put it in). The mechanic suggested that some how the msd box was wired wrong and it was reading double what it should.

Is this possible (plausible)?
Anyone got a diagram of how that thing should be hooked up?
Any other suggestions?

 

I found this thread a few weeks ago. It should help you out.
https://www.thirdgen.org/forums/elec...meter-fix.html

I am goin to fix my Tach as soon as I get a free weekend.

 

Camaros have this problem. My sisters 86 2.8 with gagues had the issue. They just replaced the cluster. The MSD shouldnt have an issue with the stock V8 GM tach. My TA has no problems. Its accurate with ProBillet Dist, MSD 6AL and MSD Coil

 

Thanks for the info and saving me from chasing a problem that wasn't there! Anyone know where to buy factory gauges? I will probably replace them all since a new tach will just make the other ones look older and we just can't have that!!!

 

are you using the stock tach wire from the coil? cuz the MSD boxes have a tach output wire in the side of the box. why not try running that to the stock cluster and see if the reading changes. just a thought

 

No need to replace the whole tach. It can be repaired fairly easily. See the thread above. The problem is usually in the "driver" for the tach which is a separate board that makes the needle on the gauge deflect and show the right number. The gauge itself doesn't normally go bad.

Lou

 

Thanks for the help all. I am infact using the tach plug on the MSD box and that article... while interesting may be a bit above my level. I think I'm just gonna buy some new gauges and call it a day!