I was driving my B4C (auto) today (Jan 29) on the highway and all of a sudden it tachs up and the speedo goes crazy, i was moving about 50 or so and it was going between 10 and 30 moving up and down, but I was just coasting. I put it down into drive to see if it would work, it did not, so I put it into second and it would let me drive it. As I was nursing it home @ 2k rpms in 2nd gear, the speedo would be moving up and down again. The it let me put it in OD again and it worked fine, the speedo still being sporatic.

~Jan 20th...The only other problem I had with it was that one day I started it up and it would not stay running. My SES light is on for the "cat #1 and #2 being over threshold" and then two "knock sensor bad" codes. The SES light was off when it wouldnt run correctly and then when I turned off the car and then back on and it was fine.

What are your thoughts on these strange occurances?

 

Cable or sensor problems I would guess.

And sounds like you need new cats and knock sensors. Remember, problems just don't fix themselves and go away.

 

no one else has had any problems like this?

 

what do you mean when you say "it tachs up"? was the tach needle fluctuating? and was the motor moving with it? im not sure what the problem is there.
your speedo jumping around could be your vehicle speed sensor (VSS) and that would explain your electronically controlled transmission acting funny. the VSS went bad in my car (non-camaro, non-GM) and my speedo would jump all over the place, it would jump up to 140mph, or down to 0, and the odometer would be moving at that speed too.

jeremy

 

Unless I'm not hearing correctly, it sounds like your tranny is slipping, no? Sorry, hard to diagnose w/out being there.

 

that wouldnt explain the wacky speedometer though. assuming the VSS is bad, the computer is getting an incorrect signal, therefore the computer doesnt know the true speed of the vehicle. that would explain the transmission operating abnormally. later!

jeremy