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Speedo issue!

PCM Diagnostics & Tuning HP Tuners | Holley | Diablo

Speedo issue!

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Old

Jun 14, 2018 | 08:57 PM

#1

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Speedo issue!

I need help. No one knows what will fix this so far. I have a 1998 Trans Am and I converted from auto to 6-Speed. I used body and engine harness from a stick car. Problem is my speedo reads 50% of what the car is doing. Is this a 98 issue? Was there 2 different pcm’s? I selected manual trans and it just won’t read right.

Old

Jun 14, 2018 | 10:12 PM

#2

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You can recalibrate the speedo in the PCM.

Old

Jun 14, 2018 | 11:48 PM

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In the hp tuner, did you put in the gear and tire size?

Old

Jun 15, 2018 | 12:30 PM

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Yes I set the tire size. I used a scanner and the main issue is the pcm is reading half the speed as well. So the cluster is showing what the pcm is sending it.

Old

Jun 15, 2018 | 12:35 PM

#5

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Change the pulses per mile in the tune.

Old

Jun 15, 2018 | 08:51 PM

#6

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Thanks a ton! All fixed!

Old

Jun 15, 2018 | 09:10 PM

#7

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Quote:

Originally Posted by Rick Speed

Thanks a ton! All fixed!

NICE!! Have fun!

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Old

Jun 15, 2018 | 10:44 PM

#8

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Quote:

Originally Posted by Rick Speed

I need help. No one knows what will fix this so far. I have a 1998 Trans Am and I converted from auto to 6-Speed. I used body and engine harness from a stick car. Problem is my speedo reads 50% of what the car is doing. Is this a 98 issue? Was there 2 different pcm’s? I selected manual trans and it just won’t read right.

check the speed sensor there could be one for auto tran an other for standard trans

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Old

Jun 15, 2018 | 11:32 PM

#9

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Quote:

Originally Posted by johngrn

check the speed sensor there could be one for auto tran an other for standard trans

Read Post #6 AGAIN. He fixed it!

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