cluster recalibration ?s

[r/tguy02]

just recently i installed an autometer digital tach/shift light gauge in my r/t. works great, but it brought something to my attention that i've sorta known all along, my factory tach is off ~200rpm's. Ever since i owned the car the secondaries on the intake seem to open up ~200rps before they were suppost to. Now with the new tach installed they are infact opening at the proper intervals its just my factory tach is wrong.
my question is, is there some sort of proceedure to recalibrate the factory tach so it reads correctly? I know this isnt critical but it is annoying...

[occasional demons]

Other than pulling the needle off and moving it....

[r/tguy02]

i thought of that but i wasnt sure if that would work, i'll try it if thats the best method though.

[occasional demons]

I can't recall ATM, but is there a needle rest at zero rpm? There isn't really a good way to tell if the first 200 rpm are showing either. Unless the fuel pump relay is pulled and you can see the cranking rpm. If it reads below 50 rpm while cranking, you know the needle is set below the rest. I would imagine cranking rpm is over 100.

[g_force58]

I was going to say what OD said. I can't think of another way to recalibrate the individual guages than that. How ever i did read a post in the how too's that dealt with the replacing the motors for the gauges. Individual guage motor problem, jerking as it operates? If it's not jerky in movement you could recalibrate it the way OD describes.

[r/tguy02]

no not jerky, just reading 200rpm's off. Guess this would be a great time to replace the LED's as well

[Gnuserup]

You could also go and buy a cheap OBDII to USB Interface like this one :

http://cgi.ebay.com/ebaymotors/OBD-OBD2 ... veQ5fTools

and compare the values.

A few weeks ago I bought one and think it´s great. It works fine and especially for the money It shows you a couple of parameters, not at least the rpm.

[rojna]

Press and hold the trip reset button on the cluster while turning on the ignition then relese the button, the gauges will perform a test, maybe that will help ???

[ZeroChad]

Meh, you're not going to fix it other than manually adjusting/modifying the needle. They are servo driven. There is probably a steady-state error in whatever control algorithm chrysler used. My signal in MS is about 150-200 lower than what my tach shows as well.

[darthroush]

Factory tach's in many cars, and even on motorcycles, read a bit higher than actual.

[Jenni]

but 200? never...


you can open the cluster, remove the needle, turn on ignition and reinstall the needle that it sits at 0 pm.

try the selftest trick before!

[BlackRoseRacing]

as others have mentioned, run the cluster self test and see where you are at after that. Otherwise OE clusters are really never dead on perfect, if they were my R/T would actually have a 9Krpm redline Vs the 8500 the AF/X hits.....

[r/tguy02]

lol thanks guys

[darthroush]

but 200? never...


you can open the cluster, remove the needle, turn on ignition and reinstall the needle that it sits at 0 pm.

try the selftest trick before!

Never? Please...

Every car I own and have owned that has come with a factory tach have read 200RPM high, coincidentally. Look around on the internet too. I'm sure you can find more than a few cases of this same problem. 200RPM on a factory tach really isn't that hard to believe. That's a hair, literally, higher than actual, as far as the needle is concerned.

[occasional demons]

200 on an 8000 scale is only 2.5% I imagine that is well within tolerance. It may be closer to accurate near idle than 8000. At idle it would be much more noticeable. And in relativity, much more than 2.5% off. Closer to 20% So it really depends on where, and how consistent it is off.

If it is off 200 throughout the range, move the needle. Otherwise, it isn't going to matter, it will be right part of the time.

[r/tguy02]

It's 200 throughout the range, so I'll probably just move the needle