Pegged TACH! Need HELP!
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Joined: Oct 2002
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From: Omaha NE
Pegged TACH! Need HELP!
I just got my 1978 Corvette back from the shop, where they had the transmission out (I was having the flywheel replaced), and as I was driving it home, I noticed that the Tachometer is "pegged out" at maximum.
I notice that the tach needle goes down a bit (into the 6500 range) when I turn the car off, but when I turn the key to ON (before starting) it pegs right back to the maximum.
Does anyone know how I can fix this?
Is this the garage's fault? I don't recall anything that the RPM indicator has to do with removing the transmission....
:confused: :confused: :confused:
Any help would be appreciated....
Thank You!
I notice that the tach needle goes down a bit (into the 6500 range) when I turn the car off, but when I turn the key to ON (before starting) it pegs right back to the maximum.
Does anyone know how I can fix this?
Is this the garage's fault? I don't recall anything that the RPM indicator has to do with removing the transmission....
:confused: :confused: :confused:
Any help would be appreciated....
Thank You!
Instructor
Joined: Dec 2002
Posts: 206
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From: WY
Re: Pegged TACH! Need HELP! (Trevelisek)
mine does that every now and then.... happens when i screw around with the battery too much. dont know why. get the car in neutral and hammer the gas.. bring it up to about 4k -5k rpms ... dont hold it there just a quick blip. mine will reset itself when i do that
edit: i should add my tach and speedo have both had the internals replaced with newer parts, possibly aftermarket and not original design- dont really know altough the previous owner told me he had to rebuild both after a bad electrical problem. sorry, shouldve added that in the first place, blame it on bad memory.
:conehead
[Modified by Yellow79, 5:03 AM 12/6/2003]
edit: i should add my tach and speedo have both had the internals replaced with newer parts, possibly aftermarket and not original design- dont really know altough the previous owner told me he had to rebuild both after a bad electrical problem. sorry, shouldve added that in the first place, blame it on bad memory.
:conehead
[Modified by Yellow79, 5:03 AM 12/6/2003]
Safety Car
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From: St. Charles IL
Cruise-In 5-6-7-8-9-11-12 Veteran
A CI-6 Car Show Winner
Re: Pegged TACH! Need HELP! (Trevelisek)
My guess is the sensor wire from the distributor to the tach is shorted to ground someplace. I remember when a dealer did a trans R & R on a pickup truck I once had, they pinched a wire between the bell housing and the engine. They then offered to cut and splice the wire without even a thought of removing it from the bell :mad
Burning Brakes
Joined: Mar 2002
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From: Louisiana, It's Always Party Time!
Re: Pegged TACH! Need HELP! (Trevelisek)
Mine has done that also, particularly after I've had to jump it off. Like Yellow79 said, I popped the throttle hard and quick and mine jumped back to "normal". I would think yours would too! Good luck!
Race Director
Joined: Jan 2000
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From: San Jose CA
Re: Pegged TACH! Need HELP! (Trevelisek)
Most of the HEI tachs will spike when you shut them off. If you shut them off at a high rpm, they might spike "over the hump" and fall to 7000 rpm. You need to rev the engine up like others said. Not as high as they claim though. 3k should do it.
-Steve
-Steve
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From: Omaha NE
Re: Pegged TACH! Need HELP! (Trevelisek)
Update!
I was driving the car last night, and the problem seems to have reset itself...I guess it was just one of those 'cold weather' things that you just have to let the car work itself through.
Thank you for all of your responses!
I'll keep an eye on the tach, after all, the circuit board may have a burned spot on it, but if it ain't broke, don't fix it.... :lol:
-Geoff
I was driving the car last night, and the problem seems to have reset itself...I guess it was just one of those 'cold weather' things that you just have to let the car work itself through.
Thank you for all of your responses!
I'll keep an eye on the tach, after all, the circuit board may have a burned spot on it, but if it ain't broke, don't fix it.... :lol:
-Geoff
