My 1990 Camaro 5 speed seems to turn 8,000 RPM easily.
I don't believe it either so I changed out the tach and electronic card mounted with the tach.
It still reads high...idles at 1100- 1500, shows 5000 Rpm at 3000.
Any ideas of what I should try?
thanks Al

try a handheld tach to see what your rpm's really are. you could put an aftermarket tach in.

mine did the same thing so i just bought an autometer tach reads perfect looks funny tho both tachs that dont match each other on rpms

And here i was thinking somthing was off in my car because it ALSO idled around 1100 RPM


This must be a pretty common problem! It seems like there are quite a few people who have this issue.


p.s. my car is a 89 Iroc 5-speed

there is a tech article somewhere on thirdgen.org explaining how to fix you factory tachs so they are at least close. i think it is in the tech articles accessed from the home page.

yeah when I bought my 91 RS the tach was way off, read 3000rpm at idle

I did the fix on the tech article, only I used a potentiometer to adjust the tach to match what my laptop said the RPM was (via ALDL cable)

got it perfect, matches the ECM readings spot on (gets slightly off at high revs, but only by like 100rpm)