Tach stops working on '02 196 with new gauges

[tmb]

We replaced our non-working telefax gauges with the new GPS gauges from Nautique parts. Randomly the tachometer will drop to zero (on both tach and rpm's on PP) and perfect pass will surge. We turn PP off and can run the boat just fine with the throttle but we have to shut boat off and turn back on to get tach to read again. Any idea what is going on? Thanks

[Fast351]

You didn't mention, but is this a new install? If it is, check all the wiring you just did, especially if the Perfect Pass was fine before the changeover. Assuming this isn't a new install, not sure what's going on, but I would troubleshoot it the following way:

1) Check the tach wire in the engine bay. Might have gotten damaged and is now intermittent and the motion of restarting engine reconnects wire.
2) Remove the wiring from the tach and see if the PP behaves normally. Maybe you got a bad tach.
3) Same for PP. Leave tach connected and remove PP wiring. See if problem goes away.

Good luck!

[tmb]

I installed the new speedo/tach back in the spring. This issue just started to happen in the past few weeks.

do you know where the tach wire connect in engine bay or what it looks like?

[Fast351]

You can see the gray wire on the 8 pin connector that goes to the dash here on pin 2. It connects through a 22K resistor to the negative side of the coil.

[tmb]

Thanks for the diagram. Do you know where this coil is located? I've looked all over the engine and I can't find it. My wife says I'm horrible at finding things as I can never find anything in the fridge and its staring me right in the face. Thanks

[ATX Jeep]

The coil will be attached with a plug wire to the center or the distributor (might be right on top of the engine). You did not specify what engine you have, I have the same boat with a Chevy 5.7 liter. If you have EFI the grey tach output wire will come from the ECM. You could check the shared grounds or ACC power wires for the tach and PP in the dash area.