Tachometer Not Working Correctly!
Thread Starter
Racer
Joined: May 2005
Posts: 277
Likes: 39
From: Billings, Montana but forever from Nebraska
Tachometer Not Working Correctly!
Took my 89 Corvette out today for a 70 mile drive this morning to blow the cobwebs out of her. In doing so, I noticed my tack saying the engine is hitting 7k rpm. Well there’s no way that’s possible! Any suggestions on what may be the cause of it?
Video I took of the tachometer during an acceleration:
https://youtu.be/Ufv5nmaZyP8
Video I took of the tachometer during an acceleration:
https://youtu.be/Ufv5nmaZyP8
Team Owner
Joined: Sep 2001
Posts: 62,154
Likes: 1,731
From: Athens AL
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
Probably the corvette aftermarket spots like Ecklers/Mid America, etc. Its the same filter for late 70s through 89 as I recall.
6th Gear
Joined: Jun 2021
Posts: 6
Likes: 2
From: Chicago
My tach has been doing the same thing (1989 6 speed). It has told me to upshift even in 6th gear. Speedometer also works intermittently (sometimes believable, sometimes inaccurate, sometimes says 0 even though at highway speeds), which also is killing my mpg calculation. Oil temp was reading Lo for a while but it seems to be working again. The horn has also stopped working.
But more concerning is the issues started with the fuse for turn signals and back up lights keeps blowing as soon as turning the key to accessory, and it will now occasionally just shut off but start right back up with no issues. Could a bad gage cluster or tach filter be the source of these symptoms?
But more concerning is the issues started with the fuse for turn signals and back up lights keeps blowing as soon as turning the key to accessory, and it will now occasionally just shut off but start right back up with no issues. Could a bad gage cluster or tach filter be the source of these symptoms?
Team Owner
Joined: Sep 2001
Posts: 62,154
Likes: 1,731
From: Athens AL
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
My tach has been doing the same thing (1989 6 speed). It has told me to upshift even in 6th gear. Speedometer also works intermittently (sometimes believable, sometimes inaccurate, sometimes says 0 even though at highway speeds), which also is killing my mpg calculation. Oil temp was reading Lo for a while but it seems to be working again. The horn has also stopped working.
But more concerning is the issues started with the fuse for turn signals and back up lights keeps blowing as soon as turning the key to accessory, and it will now occasionally just shut off but start right back up with no issues. Could a bad gage cluster or tach filter be the source of these symptoms?
But more concerning is the issues started with the fuse for turn signals and back up lights keeps blowing as soon as turning the key to accessory, and it will now occasionally just shut off but start right back up with no issues. Could a bad gage cluster or tach filter be the source of these symptoms?
Burning Brakes
Joined: Sep 1999
Posts: 786
Likes: 31
Cruise-In II Veteran
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