Code 14, VSS, speedometer, odometer- perplexed!

[spectre2lt]

Afternoon all - I'm about to pull out my hair on this one. Been chasing a Code 14 on my '91 following all the threads here and then some and still cannot solve the problem. Hoping someone has some ideas!

Here's the story: speedo had been acting up for the last 7-8 years, intermittently stopping but always coming back. Odometer always worked and the CEL came on intermittently as well (likely the Code 14 at intervals.) About 9 months ago the speedo stopped working altogether but for the occasional blip to the far right, then back to 0, then nothing (demon possession!) CEL still was intermittent and only seemed to come on during constant loads (ie smog tests - love CA!) During normal driving it would go on for a bit, then off for a while until it got on the dyno. So I get ready to smog it this year and the CEL has been off for a while even though the speedo was not working. Put it on the dyno and voila, comes on. This time, though, it hasn't ever come back off. This is the first time the CEL has stayed on permanently so I figure something finally failed outright. Replaced the VSS (easiest thing to do), CEL goes off but comes back on in a few miles and now I notice the odometer is not working. WTF?! Sure enough, Code 14 present. I rechecked the VSS connection, VSS function, all good so I reset the ECU. CEL comes back, still no speedo or odo. I replaced the cluster with a good cluster, checked the harness (no knicks, no visual indications), take it for a drive, still no speedo, odo and CEL is on. So something I did caused the odo to fail and didnt solve any of the initial problem.

I'm out of ideas here - VSS checks good, cluster checks good, wiring shows no visible damage. Yet still get Code 14 and no speedo or odo. Car is running great so I wouldn't really care about this but I can't pass smog in CA with the light on. Any ideas?!!!

Is there something in the transmission where the VSS gears tie in that could be causing the problem? I appreciate any suggestions - this one has me perplexed!

[compactfean]

Do you're gears grind while up or downshifting? If so the bearings in the trans could be bad causing the gear to not make contact with the vss. Also check continuity from the black wire to ground for the vss, continuity must be good. Check continuity from the other wire all the way up to the signal input to the speedometer. Then check continuity from speed signal output from the cluster to the speed signal input pin on the ecu, continuity should exist.

[spectre2lt]

Thanks compacfean - I took some time off screwing with this but finally did get it solved and you were onto it - the gear on the VSS was not contacting properly. I took it to a friend's shop and they just started off troubleshooting fresh; found the gear on the VSS had completely come off; hell if I know how that happened! So I had the old gear from the old VSS, put it on the new generator and voila! Looks like my original issue was a bad VSS (generator) and the secondary was a bad contact between the gearing. So now I have a spare cluster and at least know all the wiring is good. Thanks for your help!