Odo intermittant... gears?
12-27-2016, 12:00 AM
#16
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I didn't find any end play of note; it really looked impossible for the gears to slide so far out of position that they'd disengage. I did find one pin on the odo motor that had a less-than-perfect solder joint that I touched up with the iron: Looks better here: There was also a rough spot on the main board that I went after as well: (Sorry- no after shot). I haven't tested it yet; get back to you.
12-28-2016, 12:27 AM
#17
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Location: Detroit (Rock City); 1990 C4
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60 miles of success. Not conclusive; pretty sure last time I had it out it went at least 100 before beginning to stutter again.
Watch this space.
Watch this space.
12-28-2016, 04:02 AM
#18
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I wait with extreme interest. One of my cars just lost speedo and odometer then regained both. Another set of possibiiities. Maybe the ABS relay or speed sensor.
12-28-2016, 09:23 AM
#19
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Yeah, if you lose the speedo as well I'd look for something upstream. My speedo never falters, so clearly we're dealing with separate issues. Of interest though is how wildly inaccurate the speedometer is- because I've been screwing with my odo I've left the bezel and glass off and have been trying to ensure that it reads 'correctly'. "At what speed would you like it accurate?" has become the question of the day- if I set it to read dead on at 80 it's ~10% high at 40...
I'm using the speed readout in Waze as the standard.
I'm using the speed readout in Waze as the standard.
12-28-2016, 01:29 PM
#21
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fwiw, i had my speedo smoke a few months back. was a failed diode. North Hollywood speedometer fixed that, and also replaced the gears. It was working fine, but was a little bit 'jumpy' (but accurate). It still just a bit jumpy, but less so, and accurate. I was missing a tooth or two.
01-10-2017, 03:21 PM
#24
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I've been watching my speedo and odo. Sometimes I have everything working, sometimes nothing and sometimes just the speedo. Sure looks like a loose electrical joint to cause this range of faults. I will have to open the speedo up. How are people accessing the innards, careful use of screwdriver as in the video?
01-10-2017, 04:48 PM
#25
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I've had to replace my ODO gears on both of my 964's. I also had the electrical sender on the transmission go out on my 1990. If your ODO gears check out, you should confirm that your sender is sending a signal.
Note: The 1991's were updated to use the ABS wheel sender as a speed signal instead of the transmission mounted sensor on the 1989 & 1990 models.
Note: The 1991's were updated to use the ABS wheel sender as a speed signal instead of the transmission mounted sensor on the 1989 & 1990 models.
02-05-2017, 06:10 AM
#27
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I left the car out in hot sun today. It may be a coincidence but the odo started up again. Seems consistent with heat expanding the solder making a connection on a dry joint.
07-16-2017, 03:43 PM
#29
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No obvious issues on my main board. Soldering is fine, diode is ok and resistors seem fine. Time to get the motor board out. I have to remove the speedometer needle for that. A bit nervous