Why does my MPH move when sitting still when I rev
04-26-2003, 06:54 AM
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Why does my MPH move when sitting still when I rev I noticed the other day when i was sitting still getting ready to launch the car to test it out on the street when I revved the car up to 4000+RPM my MPH moved up to like 10-20MPH while the clutch was in. Why did it do that? Is there a problem, or do all do that?
04-26-2003, 09:23 AM
#2
Re: Why does my MPH move when sitting still when I rev The speedometer is a servo motor in these cars and there may be some voltage "bleeding" over from the tach circuit. When the tack is seeing an increase in voltage (for a high RPM reading) it may have an effect on the speedometer. It shouldn't do this, but I suspect that is your problem (based on the info you gave and the fact that I've not actually seen the car, this is a best guess). Good luck.
04-26-2003, 04:28 PM
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Re: Why does my MPH move when sitting still when I rev Well you sound rather knowledgable with that statement. Hmmm, well is it a concern? Is there a fix? thanks for your input!
04-26-2003, 08:42 PM
#4
Re: Why does my MPH move when sitting still when I rev It could be anything from a slightly loose (poorly connected) ground on the instrument cluster or the dash wiring to a small splash of solder somewhere it dosen't belong. I doubt that you will be able to locate the source of it (without swapping instrument clusters with another good one) without some luck and expensive test equipment (and a good wiring diagram). I'd not worry about it as long as it does not get any worse or start to cause other instruments to move as well. Just my thoughts. Good luck!
