[TempoCor84]

hey, gotta ?. i just installed a tach today. i have a 3 spd auto in my 84 tempo. i notice something. none of the gears will run out past 2200 rpms, whats up with that?the car shifts at that all the time, unless i manually shift it.

 

[Allen]

Hummmm..... that's odd. I don't know about the 84's but my 94 3 speed will run right up to 5500rpm and hold there for about a second before shifting. If I manual shift it, it goes just a little higher, maybe 5700rpm.

My guess would be.... and I don't mean to bash you or anything, but if you just installed a tach and noticed that that car only run to 2200rpm then you probably installed the tach wrong. - 2200rpm seems way to low to be shifting.

Al

 

[TempoCor84]

yeah, my car screams at just around 2500. its screamin like its about to explode. but i dont know why it would be like that, i mean, what would make it do that?

 

[GuillermoXR5i]

Likely cause

Dude, check the tach for it to be set for a 4 cyl. Most aftermarket tachs have a button (in the bottom back) you can select, 4, 6 or 8 cylinders. If you have it set for a 6 or 8 cylinder, the signal frequency will be lower, thus reading a lower RPM than you're actually running. Hell, if it's set on 8 cylinders, you're actually shifting at 4800+RPM. If it doesn't have a button, then most likely your tach is meant for 8 cylinder cars. Check the button and let us know what happens so we can help you more if you need it.

 

[TempoCor84]

nope, no button, dont say i have to get another tach, that was expensive and i drilled holes. ****

 

[GuillermoXR5i]

Question

That's a big reason why I would never drill my car and why I suggested using a velcro adhesive......What is your idle speed?

 

[olympic]

What RPM does the tach show when your engine is idling? I think Guillermo is right that the tach is set for an 8 cylinder car. Check the operating manual from the tach and it should say how to set it for a 4 cylinder. Perhaps you have to pop the cover off or something. If it's an expensive tach, it definitely should be adjustable for 4,6 8 cylinder engines.