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Discussion Starter · #1 ·
What is involved? Best way to do it? Can it be done with motor still in truck, and how? Thanks馃憤.
 

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The crankshaft position sensor is in the pass side lower timing cover and held in with 1 10mm bolt. Easy swap.
BUT GM strongly recommends having a CKP relearn done to sync the CKP with the PCM. It's a fairly simple procedure if you have access to a Tech2 or some other high end bi-directional scanner that can tell the PCM to do the relearn. Then you just rev the engine until the rev limiter cuts in and let off. Since the PCM is in the relearn mode it makes whatever tweaks it needs to the programming and you're all set. I have heard of guys getting by w/o doing it, but you might be losing performance and fuel mileage if the relationship between the PCM and CKP isn't correct. If it's way off you'll get a code. P0315 or P1336. 315 is usually a faulty sensor and 1336 is need for a relearn code.
 
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Discussion Starter · #4 ·
The crankshaft position sensor is in the pass side lower timing cover and held in with 1 10mm bolt. Easy swap.
BUT GM strongly recommends having a CKP relearn done to sync the CKP with the PCM. It's a fairly simple procedure if you have access to a Tech2 or some other high end bi-directional scanner that can tell the PCM to do the relearn. Then you just rev the engine until the rev limiter cuts in and let off. Since the PCM is in the relearn mode it makes whatever tweaks it needs to the programming and you're all set. I have heard of guys getting by w/o doing it, but you might be losing performance and fuel mileage if the relationship between the PCM and CKP isn't correct. If it's way off you'll get a code. P0315 or P1336. 315 is usually a faulty sensor and 1336 is need for a relearn code.
Hahaha, you weren't kidding, that was possibly the easiest part replacement I've ever done. Took all of ten minutes... Maybe 5. Thanks.
 

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Discussion Starter · #5 ·
The crankshaft position sensor is in the pass side lower timing cover and held in with 1 10mm bolt. Easy swap.
BUT GM strongly recommends having a CKP relearn done to sync the CKP with the PCM. It's a fairly simple procedure if you have access to a Tech2 or some other high end bi-directional scanner that can tell the PCM to do the relearn. Then you just rev the engine until the rev limiter cuts in and let off. Since the PCM is in the relearn mode it makes whatever tweaks it needs to the programming and you're all set. I have heard of guys getting by w/o doing it, but you might be losing performance and fuel mileage if the relationship between the PCM and CKP isn't correct. If it's way off you'll get a code. P0315 or P1336. 315 is usually a faulty sensor and 1336 is need for a relearn code.
Okay, Does the relearn need to be done even if I changed the CKP, cleared the code and everything is running great with no check engine light coming back on? Thanks.
 

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You might luck out. The relearn's purpose is sync the new CKP to the PCM. Basically adjusting for how many micro seconds it takes to get the pulse to the PCM. Every make, model, and brand sensor varies a bit. W/O the relearn your ignition and injectors could be firing a few micro seconds early or late. Doesn't sound like much until you do the math. At 2000 rpms a cylinder fires the plugs and injectors 1000 times a minute. Or roughly 17 times a second. Once every 60 micro seconds. Now consider that the engine rotates 720 degrees per ignition cycle. In that 60 micro seconds. How many degrees off will the timing be in say 5 micro seconds. 12掳.
The PCM will attempt to compensate for the ideal running combination and you maybe fine.
Try it and see.
 
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