LFA951

Just got my car back a week ago from getting the clutch done and yesterday I noticed that the speedometer will delay once I move forward in first, and it bounces around when cruising, anyone have this issue?

Andy1212

Sounds like a classic case of bad grounding. Im assuming this is on a late car with an electric sender.

LFA951

Actually, it's an '86, you mean the grounding by the reference sensors?

Andy1212

I dunno where the the gauge/sender grounds on the late cars, but i doubt its the bellhousing ground. Anyone else care to chime in?

TheRealLefty

I think 86 cars use the late car electric sender system, which uses an electric speed sensor that drives off the upper front driver's side of the transaxle. This sender and the wiring are easily accessible if you back the car up onto service ramps. Your symptoms sound common for a bad ground, bad connector or faulty wiring in that sender.

Early cars drive the odo from the left front hub?

dillon410021

if you tap the gauges will it start working?

LFA951

Checked all the grounds, they are all tight, didn't see any wiring on any hub...

Tom M'Guinn

Mine will stick at zero, then bouce a bit, if the car's been sitting a while. Tapping on the gauge frees it up, so I've always assumed it was sticking physically, rather than electronics/grounding, etc.

dillon410021

+1 thats what mine does

LFA951

i'll try that and see what happens....

GuyKeefer

I have a simliar problem with my speedo. On cold days I can hardly ever get it to work; tapping, smacking, cursing, or praying work get it to work. But ony warm summer days when the cars sat in the warm air for the a while, it will immediately or start up 3 or 4 minutes into the drive. I know it's not anything wrong with the connections to the gauges, so i'm assuming it's probably something with the reference sensor with mine... just need to get around to fixing it.

LFA951

Mine also was dead for 3 or 4 minutes until it got warm, but that never bothered me, I just dont like driving it warm and having it jump between 60 and 80 when I'm doing 70, annoying at best...

bigdeano

ive had mine stick a couple times but one tap of the finger on the glass and it jumps to where it should be. never had it gyrating back and forth tho, sounds like an electrical issue to me

LFA951

Tapping didn't work at all, gonna try to see if speed sensor is on tight when it gets cold...

LFA951

Mky mechanic is going to check and make sure the speed sensor is on tight