Speedometer not working correctly

[khevion]

Hi,

The speedometer of my 1993 Toyota Corolla is not working properly. It would stuck at 0 when I start driving it. Then about 10 minutes or so later it would suddenly rapidly go all the way to about 55 mph. If then I press on the brake gently or otherwise it would quickly go all the way down to 0 and stuck there and the cycle repeat about every 10 minutes. What is the most likely cause of the problem? Does it look like I need to replace the instrumentation cluster?

Thanks in advance for your insight.

[woodenhead72]

i doubt it would be the intrument cluster thats bad, its more likely the speed sensor on your tranny, which is located on the back side of the tranny almost directly under the intake. try removing that and checking the teeth on the gear, if they look worn then its probly that, or the sensor is just going out.

[ghost_ryder35]

definetly an issue with the speedo sensor / speedo cable

[94_Rolla_Guy]

my GF's car did something similar, try cleaning the connection at the transmission end the sensor is down the back of the trans against the firewall sorta buried

[ghazanhaider]

My car has the same problem, except it works after 100 kmph. Even after that it doesn't exactly work, ti very slowly goes low so that at 140 it shows 95.

I tried pulling tugging beating etc the speed sensor. Theres one bolt that's shown to be removed and it should come out (Haynes manual). It just doesnt. I'll next try removing the 3 screws.

It's a 94 1.6 Corolla special edition (auto)

[95Rollla]

mine is doing the samething it started after my altenator burnt out on me. First drive with the new one the speedo started almost working in reverse. It jumps to 35mph then around 45 it starts going down the faster i go, it even holds at different speeds on the way down if i hold a speed. I also cant get my sensor off, i tried a pry bar even and nothing.

[Puffie40]

My speedometer started doing the same thing: would stay at zero when at 60 km/h, then acellerating to 80, would kick in. 95 would be translated as 110. Odometer and trip would work fine.

On a gamble, I replaced the intrument cluster, and have not had a problem so far. All I can guess is the electronic card used to control the needle got fried somehow.

To remove the sensor, I found tapping it side-to-side with a hammer helped. Use a pair of vice grips to then get a good grip on it.

[95Rollla]

thanks. ill try the vice grips, i just didnt want to start yanking if there was somthing else to unbolt.

[95Rollla]

Thanks for the help! The hammer and vice grips worked like a charm. I tested it and its fried. I just ordered a new one off ebay.