Intermittent Speedometer

After a few 100 miles of driving, I have to now say I think the problem is worse.
Not only does the speedometer drop to '0' now, but it completely freaks out sometimes, I wish I could take a video of it... it's kind of funny actually.
Also, there are 2 other key symptoms that have now appeared.

1. I can now sometimes feel the engine changing when the speedometer drops to '0' vs. when it does not. (you can really feel it when it comes to life and suddenly shows the proper speed again, but only sometimes... not every time.)
2. A couple of times, cruise control could not be enabled, yet the speedometer showed the proper speed. Also, the cruise control dropped out once, yet the speedometer still worked.

#1 is probably a bad timing issue waiting to happen and is not good...
#2 tells me that the Instrument Cluster is actually part of the problem, it is not sending the "more precise 4 pulse signal" to the ECU properly all the time.

Based on the this new info and the prior info, I am tending to think it is both the Cluster and the Sensor, they just are failing at different times.

When the wires were spliced together the ECU should have been receiving at least some kind of signal from the sensor, all the time, the Instrument Cluster was essentially bypassed at that point, at least all the time the Sensor was operating correctly.

Of Course, still no dang CEL... never! You'd think the dang ECU would have tossed an error at this point.

And... of course, it's an intermittent problem, so it's a total PITA to troubleshoot.

Dang older vehicles, at least this one is worth the trouble!

 

Every time I changed my speed sensor, I had to change the nylon speedometer gear as well. Mine always showed slight wear compared to new. When I put a new one in, the speedometer started working properly again. When the speedometer drops to zero and stops working, the nylon gear stop spinning. The metal gear in the transmission that it turns with, keeps spinning and will ruin the speedo gear. After changing the speed sensor three times, and a new gear, it was determined the cluster was at fault. After changing the cluster and putting in a new gear, everything has been fine with mine for the past year.

 

Thanks for your info @charles08tacoma.
I think I am to that point as well, going to have to replace both.
Was the nylon gear a separate part from the sensor?

Also, has anyone ever dealt with the people at ToyotaPartsOverstock.com?
The Instrument Cluster is significantly cheaper there than from my local dealer, of course.

 

The speedometer gear is a separate, dealer only part.

 

I removed the Speed Sensor, just to look at it and see if the gear was smoothed out or anything else obvious, I didn't test it electrically yet.
The gear looked good, so I just stuffed it back in for now.

Based on @charles08tacoma's info, I decided to just order a new Combination Meter first. I will do the sensor later.
Turns out you absolutely have to order the Combination Meter from the local dealer, even had to go in and have the parts guy order it, cannot do it online they say.
Apparently, if the order for the replacement Instrument Cluster (aka, Combination Meter) does not come from a dealership's parts or service dept, you'll end up getting a unit that has not had the odometer info programed into it. Understandably, they are a little weird about it. Legalities and all that.
Told me 3 times "Please do not drive it much if you can help it."
I also have to exchange the old one when I get the new one.

Now I wait.

Thank you for all the help from everyone! I will update once I receive the part and get it installed and checked out.

 

Fingers crossed wishing you the best results.

 

Got the Instrument Cluster, got it installed, drove about 7 miles and the speedometer needle started doing the same thing.
<insert lots of cursing and cussing here>

I then tested the speed sensor in the way @Jimmyh was suggesting, by doing very slow turning of the gear and watching for a voltage spike occur.
That worked, I could actually see it turning "on" 4 times per revolution.
Even tho the sensor tested ok, at this point I knew it wasn't, so I ordered, and installed a new Speed Sensor and 28 tooth gear last week.

Problem solved! No more issue after 400+ miles!

I ended up doing exactly what I was trying to avoid and just threw parts at the problem. Ah Well.
At least I did the work myself and learned more then a few things about vehicle electrical systems along the way.
I hope I do not have to every worry about it again, or at least not for another 150k!

 

Glad you got it resolved! Electronics can be very frustrating at times!

 

Glad you got it fixed. That gear got chewed enough for it not to work each time I replaced my sensor. New cluster & gear fixed mine. It’s been working perfectly past 6 or 7 months.

 

@Jimmyh you got that right! Especially more so in a vehicle it seems!
@charles08tacoma Glad yours is still working! Sounds like this is a common issue.

In my case, I think it was both the Cluster and the Sensor having intermittent electrical issues, just replacing one or the other would not have done it, had to be both.
The old gear didn't seem to be worn down much, setting them side by side you could not tell a difference, other than the new one having pink markings on it and the old one stained from tranny oil.
The old gear is saved, "just in case" I guess... time will tell!

Thanks again for everyones help and encouragement!

 

Mine does same tap cluster it works on off. Seem like it has to warm up the cluster