Dear All,

The following issue has arrived with no prior warning signs.

Upon driving back to work (1.5 miles away from home) I noticed my 2003 350z with auto transmission began shifting with a jerking feeling, from 1st to 2nd, 2nd to 3rd, as well as downshifting from 3rd to 2nd and so on.

I also noticed weirdness in the tachometer. Instead of reading revolutions smoothly, the needle seems to jump up and down abruptly, in an almost oscillatory manner. I also noticed the temperature needle reading in the middle of hot and cold, jump to cold and back to normal (this is more infrequent than the tachometer needle jumping).

Finally I noticed the ABS, brake, TCS off, and SLIP lights turn on all at once. While the car is running, the lights turn off from time to time but remain on for majority of the time. When they turn on and off, they all of the lights mentioned above turn on and off at the same time.

Anyone have any idea what could be causing all of this to happen simultaneously, completely out of nowhere?

Any help is sincerely appreciated. I am not very mechanically savvy.

Thank you

 

Check your battery terminals and all the grounds you can find.

 

The problem you describe should return one or more codes.

I’m guessing, but it’s likely you are experiencing a problem with the cam shaft or crank shaft position sensors. Does the car seem more difficult to start?

--Spike

 

Thanks for the quick replies all; the battery terminal appeared fine and the check engine light came on slightly later than when the symptoms actually appeared.

Upon scanning, we found out it was the VSS (vehicle speed sensor). Without having the time to wait for a new sensor (the z is currently my daily) we cleared the code and unplugged the sensor and put it back in. Everything seems to be fine currently. Do you think this sensor would go bad anytime soon?

Again, thanks for your help!

 

^^ That’s a tough call. You did it correctly (cleared the code and unplugged/re-plugged the sensor). Sometimes just cleaning a sensor cures the problem.

I would keep driving the car. If the problem returns, you know.

--Spike

 

If you have nothing better to do, you can pull the sensor, give it a good spritz with carb cleaner and gently clean it with some very fine grit (800) sand paper. Add a few daubs of dielectric grease to the connector leads and put it back together. Sometimes, crud gets built up on the VSS and changes the resistance reading that's sent to the computer. You can probably find a how-to on Youtube.

 

^^ Exactly… Cleaning a sensor connection sometimes fixes the problem. It’s a good starting place.

--Spike