speedometer reving with tach
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speedometer reving with tach
Ok, this is what happens. When I was driving, the speedometer would rev up with my engine. When I take off, it acts normal until I hit higher RPM's (maybe 3,500 and up). When I am cruising, it seems to work fine. When I got on the interstate, it worked fine unless I gave it alot of gas, then it would rev up higher than I know I was going.
Last edited by ggflyguy; Feb 10, 2007 at 04:15 PM.
Methanol Drinker
Joined: Jul 2006
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From: Dallas, Texas
That's a pretty strange problem...
Firstly, have you added any aftermarket electrical devices (i.e. Tachometer, EMS, Ignition Booster, etc)?
What year model?
Have you done ANY recent work on the car? If so, what did you do?
My first thoughts on the matter are that you are getting some RF noise through the electrical system and causing the problem.
Firstly, have you added any aftermarket electrical devices (i.e. Tachometer, EMS, Ignition Booster, etc)?
What year model?
Have you done ANY recent work on the car? If so, what did you do?
My first thoughts on the matter are that you are getting some RF noise through the electrical system and causing the problem.
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Joined: Oct 2005
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93 Prelude si with H23A1. I replaced my stereo and added an amp, but it worked fine after that. Then I started working on my egr issue. I have removed the egr valve and cleaned it up and tried cleaning the ports. It still hasn't fixed my egr problem, but now I have this happening. Would it have anything to do with disconnecting the vacume on the egr valve and plugging it to keep the engine running smooth? I figured I would disengage the egr valve because it was running rough when it warms up. It fixed this problem until I can remove the intake for a good cleaning. I don't know how this would affect the speedometer though.
Methanol Drinker
Joined: Jul 2006
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From: Dallas, Texas
Check all the grounds on the engine and chassis to make sure that they are good and solid without any corrosion.
I would also put a digital voltmeter on the engine and check the reading (at different rpms, including the ranges that you are noticing the problem) to make sure that you're not getting any surges or drops in the voltage. That kind of surging/drooping of the voltage usually triggers a check engine light because it will make sensors seem bad, but there is the random possibility this could do something like that. Don't be too concerned if you see between 13.5 volts max and about 11 volts min.
If everything looks good you could try changing the VSS (Vehicle Speed Sensor) and see if that fixes your problem. It could be just that it is getting a faulty signal and/or catching some odd interference from the voltage system.
I would also put a digital voltmeter on the engine and check the reading (at different rpms, including the ranges that you are noticing the problem) to make sure that you're not getting any surges or drops in the voltage. That kind of surging/drooping of the voltage usually triggers a check engine light because it will make sensors seem bad, but there is the random possibility this could do something like that. Don't be too concerned if you see between 13.5 volts max and about 11 volts min.
If everything looks good you could try changing the VSS (Vehicle Speed Sensor) and see if that fixes your problem. It could be just that it is getting a faulty signal and/or catching some odd interference from the voltage system.