Code 634?

1992 FORD F-150

192,000 MILES

FIXITMR

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9,990 POSTS
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brother has this vehicle and the trans is early/hard shifting. he changed TPS on advice and now idle is higher and early shifting. before it was late/hard shifting. i tried to read codes but the info on reading them was way too confusing due to all the don't do this stuff. including the 2-digit codes vs 3-digit codes. i did see a 634 code in sequence though. don't know what that actually refers to. before his CEL was off and on now it's on steady. thanks

Oct 9, 2012 at 3:09 AM

FIXITMR

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oh yeah, it's a 302 and it has a transmission kickdown cable, i think. has two cables, one is cruise. hitting gas does increase shift times somewhat but still shifts harder than should.

Oct 9, 2012 at 3:12 AM

KASEKENNY

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18,907 POSTS

This code is for the Manual Lever Position sensor. MLP. So, I am attaching the info for this below.

Basically, we need to start with checking the voltage on this and then the most likely cause of this is the seal is leaking.

You can confirm this by checking the voltage on this and I am attaching the diagram that will help.

https://www.2carpros.com/articles/how-to-check-wiring

Please see the info below and then let us know what you find with this.

Thanks

Images (Click to enlarge)

Apr 21, 2022 at 8:38 AM