I recently purchased a reman 4.6 to replace my current 4.6. I have both motors out and in the process of putting all new sensors in everywhere. The original motor has 12mm threads for the knock sensor and the new motor has 8mm threads. I can't find a sensor with 8mm threads. Any suggestions on what to use.

97 f150 4.6 2wd xlt automatic

 

Have you taken the engine serial numbers to the Ford parts guy to see if they made a change and are now the only one that sells the right sensor?

 

no I haven't. Would they know that from a number on the block. I am waiting to hear from the company I got the engine from also

 

Both the company and Ford should be able to tell you based on the engine serial number and manfacture date. It is odd that you cant find them at a good parts store but it is possible that Ford made a change and did not produce the type you need for very long and the secondary market decided for profitability reasons not to produce them. I'd try to talk to a good Ford parts man.

 

Problem solved, I drilled the hole out and tapped it.

 

Excellent. Glad it worked out.