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Jul 19, 2021 | 03:54 PM

Markharvey

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Need help

I just bought an 01 f150 guy said he swopped the 4.6 to a 5.4 didnt change the ecm and then put in a new tranny. Problem is it wont go to od and it would kick down to pass anyone or goin up hills. Anyone have a clue?

Jul 19, 2021 | 07:13 PM

Stonedpony

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Quote:

Originally Posted by Markharvey

I just bought an 01 f150 guy who said he swopped the 4.6 to a 5.4 didn't change the ECM and then put in a new tranny. The problem is it won't go to od and it would kick down to pass anyone or going up hills. Does anyone have a clue?

Depends if the 4.6 was a PI engine or an NPI engine on the wiring harness and the 5.4 as well. Look on the passager side of the truck just above the exhaust manifold and post what is wrote on the engine block. You also need to know which engine he took out of the truck. It can be made to work, but I and others need that information.

If he placed the wrong transmission in the truck, say a 4r70w to a 4r100w or even an older style the PCM will not like it. You need to find out what transmission he placed in the truck with the model number and year as well as which one came in the truck.
Your problem could be just a PCM flash maybe or maybe not.