89 gmc 2500 4x4 350

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89 gmc 2500 4x4 350

Unread post by doublejippo » Mon Jun 30, 2014 12:48 pm

the speedometer stops working and makes the transmission downshift, we replaced the vehicle speed sensor with no luck


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Re: 89 gmc 2500 4x4 350

Unread post by carriedi » Mon Jun 30, 2014 5:45 pm

check out your instrument cluster. speed sensor sends info to the cluster and then it goes out to other computers. If the cluster turns off the pcm sees no speed reading

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