My Dumbass Tach Problem

Wavey · 10-28-2005, 05:01 AM

After 5 months of sitting on jackstands, the Carrera finally got fired up late yesterday.

Reconnected the battery (after a trickle charge), cranked for a few seconds, it immediately built oil pressure, then it fired right up. I was expecting at least some smoke from accumulated oil in the case, but there was nothing. Settled into a nice idle, like I had just parked it the day before. Got a few details to wrap up over the weekend - it should be ready to go out for corner weighting and alignment by Monday.

Now the problem - everything appears to work normally except the tach is dead. All of the work was done on the suspension and brakes, but I did replace the master cylinder so I suppose I could have pulled a wire off back there. Also pulled the rear heater blower to get access to the shocks and I believe there are some DME connectors in that vicinity.

Any quick thoughts on what to look for before I tear back into it?

Rot 911 · 10-28-2005, 05:33 AM

Mine sticks every now and then, but tapping on the glass face of the gauge gets it working. Did you try that?

Wavey · 10-28-2005, 05:53 AM

Well, of course! Isn't that the first attempt at any repair?

Early_S_Man · 10-28-2005, 07:18 AM

Short of digging out an oscilloscope ... put a logic probe [set to CMOS levels, power leads to gnd & +12 Volts] on the tach input terminal, and see if you have any pulse activity ...

Lorenfb · 11-07-2005, 06:29 PM

"Now the problem - everything appears to work normally except the tach is dead. All of the work was done on the suspension and brakes, but I did replace the master cylinder so I suppose I could have pulled a wire off back there. Also pulled the rear heater blower to get access to the shocks and I believe there are some DME connectors in that vicinity." - Wavey -

"I believe there are some DME connectors in that vicinity."

Yes there are, but not for the tach. Try keeping your hood closed so no
damage can occur there when you're doing DIY things (polishing).

Wavey · 05:08 AM

For those of you unfamiliar with Loren, here's the deal: Loren has a big boner about performance chips - he hates them, especially those from one particular supplier. Occasionally someone will post a question about chips, and Loren will chime in and make a complete a$$ of himself. Do a search on his screen name, you'll see what I mean. It then turns into a World-against-Loren situation, and when he's finally backed into a corner he starts stalking (ie this thread and another one) the people who call him out. That's what is going on here, and the purpose of his post above. This behavior has gotten him banned from this BB in the past, yet he continues on this self-destructive path. One can only hope he's ultimately successful some day.

BTW, there's a $100 challenge on the table to prove his ridiculous allegations about chips, and he is unable to meet the challenge. Hence this current round of stalking me.

What a guy! At least he has some entertainment value.

Wavey · 11-08-2005, 03:00 AM

Quote:

Originally posted by Early_S_Man
Short of digging out an oscilloscope ... put a logic probe [set to CMOS levels, power leads to gnd & +12 Volts] on the tach input terminal, and see if you have any pulse activity ...

Did that, have a signal and a ground, tach appears to be dead. It's in a box to Palo Alto as we speak. Thanks Early S!

tsuter · 11-08-2005, 04:39 AM

Quote:

Originally posted by Kurt V
Mine sticks every now and then, but tapping on the glass face of the gauge gets it working. Did you try that?

Go here for how to fix a sticking tach needle...

Sticking Tach Needle.... Whats the fix