Yet again as soon as I fix something another issue arises. Long story short I have had the car for 14 years and just got finished putting the new engine and rebuilt trans in. Drove it around no problem and the speedo worked no issues. I have been playing around with the exhaust setup and changeD it a couple times in the last month or so. This trip to the exhaust shop the speed was not working and it worked the last time I drove it. After a little bit of research I changed out the speedo and the clip to the speedo with a new setup. Just finished up tonight...andddd nothing has changed!

Any ideas on what else this could be? The new clip had a purple and black wire the old one had a purple and white wire. The new clip wire was a little heavier gauge wire. Could this be the issue?

any help woud be appreciated! I have been working on this project for 2 years now and this is literally the only thing wrong right now and it’s a very annoying problem guessing your speed as you drive 😂

Thanks!

 

Check the plastic gears behind the VSS sensor.
https://www.corvetteforum.com/forums...ease-help.html

 

Go back to the guy who rebuilt your transmission and have him check the parts associated with your Speedometer.

If that doesn't help call BATEE.Com or watch some of his videos. Some of the electronic components used in the digital dashboard had a life expectancy of 15 years, my C4 is 32 and most of the old components have been replaced after my dash fix.

My Speedometer used to come on and off because of a bad ground behind the Digital dashboard. There are so many wire connections that should be cleaned and re-attached to get better connections. Batee saved my bacon and made my dashboard work like new again.

 

Agreed if you suspect it's the digital dash^^^.

Just wanna add... When newly acquired, my C4 was in the midst of a T56 conversion. The PO sold the car to me before addressing the speedometer. One thing albeit this is on a '90, with a non-functioning speedometer, on decel this C4 would always stall. After I fixed the speedo, that problem went away so based on that if you don't have that "decel stalling," then inside the trans is probably all kosher and the VSS is talking to the ECM as it should. In the interim, I used a GPS speedometer APP on my phone with a suction cup phone mount and double clutch coming to a stop to prevent the annoying decel stall!

Oh one more thing...Idk if the factory installs do this but when you changed the VSS connector, did you twist the pair of wires? This is recommended with any magnetic type signal output.

 

yes I twisted the wires. Is there a way to test the clip to confirm the ground and power source are good before I get into messing with the new speed sensor again?

 

https://www.corvetteforum.com/forums...post1595250402
Spin it like in the ^^^link but just do it with everything connected and observe the speedometer.

 

I haven’t driven the car in a couple months just because the speedometer not working drives me crazy! So finally this weekend I got a chance to start some research on why the speedo isn’t working but no luck yet. So far this is what I’ve done:

Speedo was working one day and then stopped working out of nowhere. So I ordered a new sensor and clip that goes into the sensor (2 wires on the clip)

Installed new sensor and clip - nothing changed. Speedo still wasn’t working.

I took the old sensor and spun it on a drill with a meter plugged into it and appears it’s in working order.

To avoid removing the newly installed sensor I took the old clip I had cut off when I replaced with the new clip and ran a couple of wires off of that old clip to my meter while plugged into the new sensor and same thing...appears correct. I had the car in the air at this point and put into drive and gave it a little gas and the numbers on the meter were going up and down as I accelerated and decelerated.

I believe my next step should be to see if the wires on the harness of the car itself are working. How would I confirm that there is power to the wire (what should it read) and also how would I confirm the ground is good?

Is there a way to confirm where the 2 wires run into the ecm? Can I just rewire these 2 wires to eliminate a wiring issue?

After confirming the wiring itself is good or running new wire to replace it I guess the step after that would be the dash itself and seeing if there is an issue there?

 

Just got my cluster back from Batee. That is very possible your problem.

 

Update:

I removed the cluster and then plugged it back in, checked the fuses again and noticed the ecm fuse was blown (it wasn't before), replaced the fuse ......and now I have a speedometer again!!!!!

 

I'm having trouble with my avg MPG being not correct. I will check the fuse. Did yours run properly with the fuse blown?

 

I'm not sure if it worked before, I never really looked at that I just assumed 5mpg with my 396 stroker

 

I'm pretty sure my mileage indicator is not accurate or I'd be filling up every half hour! Gotta say it's the least of my worries with all the other issues I need to address.

 

Had a chevy dealer look at it and they are not sure. Said possible the ECM