In the last six months I’ve occasionally seen both the tach and the speedometer slowly peg when I start in the morning. My mechanic says to not worry about it but I do. Any comments, suggestions of the cause and fix? The car is a 2005 Toyota ECHO with manual transmission.
Some cars do a self check of the gauges on start up. As long as the gauges work I would not worry about it.
Your Owner’s Manual will tell you if this, in fact, normal behavior – or if it’s some kind of warning. If the Manual says nothing, and if the problem is new and happens “occasionally”, it’s likely something electrical or electronic (“bad ground” is a favorite). If so, it will be almost impossible to diagnose until it becomes regular. (Unless somebody has encountered the same weird problem in other cars like yours.)
I’m assuming that the Engine is NOT racing to 7k rpms when this is happening?? It’s just idling normally, but the tach is just creeping up??
If the engine is racing along with the tach then YES you have a problem. If not and after the tach and speedo are working properly then I wouldn’t worry about it.
My 2010 Corolla has always done that. They jump to max and then drop to normal.
There is often a power surge when electronics are turned on. This is likely the cause, and may be normal. If it is an occasional issue, then it could be a failing circuit that buffers the system from power spikes. Since it’s out of warranty, you can’t do much more than watch it. Your observations might be useful if the tach or speedometer ever fail. I am not saying that they will fail.
I had the same situation with my 2000 Ford Windstar when the battery was on its way out. Apparently, when the engine started, the alternator output may have been high because of the weak battery. At any rate, when I replaced the battery, the problem went away.
Ive seen many vehicles do this as a sort of self test, usually high performance cars…it’d be funny to me to hear that the Echo did a self test like this…did it do this prior but you never noticed? Do they work fine otherwise? If so …keep on motorin.
I’ll answer several of the questions posed. When the speedometer and tachometer peg the engine is just starting up and does not speed up. And, no, this phenomenon is fairly recent. I’d say the last six months or so. But I thought the ECHO was a high performance vehicle…at least compared to a bicycle. My mechanic did say he’s seen this in some other cars of different makes. There is no mention of this behavior in the Owner’s Manual.
I recommend that you have the battery load tested. I still think your battery may be weak.
Triedaq: Thanks for the suggestion. I’ll have the battery checked at my next tuneup or, if the problems gets worse, sooner. I’ll report back to the list.
I think you will find that you have a computer of some type between the speedometer and tach and their respective sensors. The sensor data is digitized and sent to the dashboard. The meters then use the digitized information to control the applied voltage to the meter movement.
What is happening is that the digitized information is being delayed momentarily and the meter movements get full voltage. The computer, sometimes called the Body Control Module, is not booting up as fast as it used to. They use solid core memory and this type of memory develops “holes” in it, so the processor has to do some “work arounds”. It is designed for this so the only effect you see is the meters moving at start up.
The cost to replace the BCM is not worth it for this problem.