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Speedometer FREAKING OUT!

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Old Sep 6, 2007 | 11:52 PM
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Default Speedometer FREAKING OUT!

After my full out heads, cam, valvespring, oil pump, timing chain swap I started the car it actually drove it to Jiffy lube for a radiator flush. While driving I noticed the speedometer was TOTALLY FREAKING OUT! It was fluctuating from 10 to 50 mph and then back down then back up then steady then down. Is this normal after such a big engine upgrade? Will a computer tune fix the problem?

Thanks!
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Old Sep 7, 2007 | 09:18 AM
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No that is not normal and a tune will not fix it. I can't think of anything that would cause that after a H/C swap. Make sure all of your grounds are connected and tightened properly. Other than that it may be a pinched or damaged wire, as the speed sensor wires do pass at the back of the heads.
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Old Sep 7, 2007 | 09:34 AM
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it's just stretching out for when you womp on it.
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Old Sep 7, 2007 | 11:00 AM
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I'll check the grounds and the wires on the sensor at the tranny. I'm pretty sure that all the grounds are connected firmly to the back of the heads. Do you know by any chance which head the speedo wire grounds to? Driver or Passenger?

Thanks again
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Old Sep 7, 2007 | 11:12 AM
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All the grounds are on the drivers side head. Three ground eyes on two different bolts. The passenger side head has the dipstick tube and a wire strap.
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