Hi guys,

Went out for a drive yesterday on the highway. As I was going on the onramp and accelerating, the tachometer gauge violently jumped up from 2.5K to 3.5K RPM bounced around a bit. Was scared that I had the transmission 'flare' problem, but the tranny felt smooth as per normal.

Now my tach gauge 'bounces' and seems to be inaccurate from what the engine RPMs are really doing. Seems to be a margin of error of 10-30% over the normal RPMs.

Also when I let go of the gas, the gauge takes a while to fall and sort of floats until it finally recesses to the proper RPM level.

Anybody have any ideas? Does anyone have a servicing manual where there is a reset procedure or something? I don't feel like shelling $1K+ to change the instrument cluster....

Thanks!

 

Any warning lights? I'd be surprised if it's a cluster issue.......but it could be an engine speed signal problem. I don't understand your concern about 2000 -2500 RPM during the accel onto the highway? If the tach is not going to zero during the "bouncing" it sounds like it could be actually "hunting" and the slow decel of the RPM when you let off on the throttle could be genuine. Take it somewhere and get it diagnosed with the use of a scantool.

 

Changed my original post. Sorry I should have said it rapidly jumped from 2.5K to 3.5K, then settled and kept 'bouncing'. There were no warning lights at all. Can I still trust my cluster?...

Even now, the needle looks like it 'loosely' connected to the real RPM signal values. Maybe a bad ground or signal? It is only isolated to the tach and not the speedo.

I want to grab an OBD off someone and run it to see if it matches or it is indeed the cluster.