When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Ok so the other day I was enjoying a nice ride in my C5Z. I was driving on an older 2 lane highway, that is a little rough. Its not the nicest road and its not necessarily the smoothest, however there are no potholes or big dips or anything ridiculous its just not the smoothest asphalt.
Hope I have explained the road clearly enough. I drive this road every time I drive my Z which is once or twice a month, and I have NEVER noticed this before. I was cruising at 55-60 MPH at most just like I do every time I drive the road.
As I was driving I really noticed the road seemed to be rougher than I remembered it in the past and my RPM needle was jumping up and down slightly, maybe varying 2-300 RPM's on the cluster. I pushed the clutch in and held it and the RPM went to idle and the needle was just as smooth and did not jump at all. I let the clutch out, continued driving and it stopped for a short time then started jumping around again.
I have no current or history codes, also I did not hear or feel a miss at all when I stopped in the driveway and watched and listened to the car.
The RPM needle was the only needle that I noticed doing this.
If it matters the Z is completely stock.
Last edited by Ferg03 Z06; Jul 7, 2015 at 05:14 AM.
From: In a parallel universe. Currently own 2014 Stingray Coupe.
C7 of the Year - Modified Finalist 2021
MO Events Coordinator
St. Jude Co-Organizer
St. Jude Donor '03 thru '26
NCM Sinkhole Donor
CI 5, 8 & 11 Veteran
I understand what you are saying, but I have not heard anyone report a similar problem here on the forum. Perhaps post this in the C5 Tech section and see if someone there has some suggestions.
I have a similar problem that my tach works sometimes and not at others. When it quits, I can sometimes tap the dash top above the cluster and revive it. It often stops working when I hit a bump and starts sometimes....when I hit a bump. I read here, but cannot seem to find it now, that there are several nuts on the circuit board that retain the tach and create the connection for it to the board/ribbon cable and that they are known for loosening and creating a poor connection. If I find the post, I'll try to post it here for you...er, us!
I helped a friend who had issues with the IPC "going crazy" at times. The previous owner had the issue and the dealer had replaced the IPC with no change. So my friend got a good deal on the car. I determined it had to be a ground or power issue. Had him pull the IPC so we could check the circuits. He immediately found two terminals in the connector that feeds the cluster were not fully seated. He just pressed them in and no more issues. One was a power feed and the other was a ground.
I have a similar problem that my tach works sometimes and not at others. When it quits, I can sometimes tap the dash top above the cluster and revive it. It often stops working when I hit a bump and starts sometimes....when I hit a bump. I read here, but cannot seem to find it now, that there are several nuts on the circuit board that retain the tach and create the connection for it to the board/ribbon cable and that they are known for loosening and creating a poor connection. If I find the post, I'll try to post it here for you...er, us!
I have a 2002 Vert that does the exact same thing.
I now know you have an issue on one road. Why don't you drive on a smooth road somewhere and see if it happens there.
Also always pull your Dash DIC trouble codes to see if anything is there.
In my original post I said several times I pulled DIC codes with no history or current codes. I also was less than a mile from my final destination, and I have not driven the car since. So at this point I can't try a different road, but I surely will in the near future.
I will also try to check the connections if the problem persists in the future, thank you for that advice
Last edited by Ferg03 Z06; Jul 6, 2015 at 01:51 AM.
I understand what you are saying, but I have not heard anyone report a similar problem here on the forum. Perhaps post this in the C5 Tech section and see if someone there has some suggestions.
I think this is what he meant. I didn't understand it either but decided it was not important to understand it, just that you had gauge issues.
"I pushed the clutch in and held it and the RPM went to idle and the needle was just as smooth and did not jump at all. I let the clutch out, continued driving and it stopped for a short time then stopped jumping around again."
I think this is what he meant. I didn't understand it either but decided it was not important to understand it, just that you had gauge issues.
"I pushed the clutch in and held it and the RPM went to idle and the needle was just as smooth and did not jump at all. I let the clutch out, continued driving and it stopped for a short time then stopped jumping around again."
That's my fault on the typo, its fixed now. I will check it again after driving it in a few days and will report back.