Crank and Cam Positioning Sensors

[firsthere]

While I'm replacing the engine should these sensors be replaced or just reuse the Originals?
I definitely don't want to go back and replace the old crank sensor behind the starter a few thousand miles down the road, so though it wise to replace them all now.

Will a relearn need to be done regardless as it is a different block, crank, and cam or luck of the draw that it all matches up?

 

[strutaeng]

Umm. The original sensors seem to be very good and don't commonly fail.

I replaced my cam sensor from AAP (BWD brand IIRC) on my 06 Suburban a few years ago because it had a very small leak. Hindsight, I should have taken the time to simply figure out the O-ring size it had and replace that. I did retain my original sensor to do that down the road and have it as a spare...

A few months ago I completely tore down that same engine for a freshen up. I reinstalled the aftermarket new-ish cam sensor and the original crank sensor. No issues.

I didn't need to do the relearn in any of my cases.

 

[Fless]

It's recommended to do a CASE relearn if either one of those sensors is replaced. People have experienced general misfire codes sometimes, so it's something to be considered. Most times it's fine, but doing the relearn might save you some misery.