As the title says..... when I start up my 93 auto, the needle goes up to 50-70 mph, then slowly bounces down, it also occasionally does this when coming to a stop. The first time it did this; I checked the fluid level, and it was about 2 qts low, filled it up, and the problem went away, now its back, and there is plenty of fluid. Any thoughts? I do have another tranny, so if its goin out, thats fine... I will also throw another motor in at the same time.

 

 

no thoughts guys? Not even a "try replacing speed sensor" ? Has anyone ever seen this before? It only bounces when I start the truck, and when I come to a stop


I am very confused.

 

Mine did similar things when I started it. It took me forever to figure it out. I thought maybe it was a bent spedo cable but it was actually the little plastic gear on the back of the transmission. I got one from the pick a part and it fixed everything.
Hope that helps

 

93 4Runner speedos are electronically controlled. Often times the sensor in the tcase goes bad, causing the exact symptoms you are describing.

I would look at checking/replacing that first, then then speedo itself.

 

Sorry for the wrong info.
I only have 1st gens

 

Ok... thanks for confirming what I thought. I got stuck in some deep water in april. Guess its finally showing signs of the abuse....lol

 

for the speedo to move, it requires a signal from the speed sensor. if the signal from the speed sensor is unstable, the spedo may bounce. so it may be the sensor itself, or could be a problem in the wiring causing noise on the wire, such as a bad ground or loose connection somewhere.

 

mine is 10x worse than yours, while driving it will sit at 0 and while parked and idling it will randomly bounce to 90-110mph and back to 0. I ended up just unplugging the vss so it stops moving all together until I can find a replacement that doesn't cost $250