[Kenzen]

I found this process which may enable the relearn without a scan tool - wouldn't hurt to try (but fix the vent valve first):

The crankshaft position (CKP) system variation learn procedure is done better with an scan tool, but if the Crankshaft Variation Relearn is not accessible through your scan tool (some truck applications 1998 & later), perform the relearn in the following manner:
1. Turn off all of the accessories. With the Air temperature sensor and Coolant temperature within 5 degrees (Centigrade) of each other, start the engine and let it idle in Park or Neutral for two minutes. 2. Accelerate the vehicle to 55 mph at part throttle. Cruise at 55 mph for 8- 10 minutes until the engine reaches operating temperature.
3. Cruise at 55 mph for another 5-6 minutes.
4. Decelerate to 45 mph without using the brakes, and maintain 45 mph for 1 minute.
5. Perform 4 deceleration cycles, without using the brakes, of 25 seconds each where no specific speed is necessary. Returning to 45 mph for 15 seconds in between deceleration cycles.
6. Accelerate to 55 mph and cruise for 2 minutes.
7. Stop the vehicle and idle for 2 minutes with the brake applied and the transmission in Drive (automatic trans.) or Neutral (manual trans.) with the clutch depressed.

Read more: P0315 Chevrolet - Crankshaft Position System Variation Not Learned

 

[Kenzen]

...and another note, it seems any P code can prevent the PASSLOCK relearn from happening...need to fix the vent valve.

 

[desgrunner]

I found this process which may enable the relearn without a scan tool - wouldn't hurt to try (but fix the vent valve first):

The crankshaft position (CKP) system variation learn procedure is done better with an scan tool, but if the Crankshaft Variation Relearn is not accessible through your scan tool (some truck applications 1998 & later), perform the relearn in the following manner:
1. Turn off all of the accessories. With the Air temperature sensor and Coolant temperature within 5 degrees (Centigrade) of each other, start the engine and let it idle in Park or Neutral for two minutes. 2. Accelerate the vehicle to 55 mph at part throttle. Cruise at 55 mph for 8- 10 minutes until the engine reaches operating temperature.
3. Cruise at 55 mph for another 5-6 minutes.
4. Decelerate to 45 mph without using the brakes, and maintain 45 mph for 1 minute.
5. Perform 4 deceleration cycles, without using the brakes, of 25 seconds each where no specific speed is necessary. Returning to 45 mph for 15 seconds in between deceleration cycles.
6. Accelerate to 55 mph and cruise for 2 minutes.
7. Stop the vehicle and idle for 2 minutes with the brake applied and the transmission in Drive (automatic trans.) or Neutral (manual trans.) with the clutch depressed.

Read more: P0315 Chevrolet - Crankshaft Position System Variation Not Learned

Similar to what the PCM vendor sent me... I will try this procedure... "Thanks a million" from figid Ohio...

 

[desgrunner]

P0315 is common after a replacement of the PCM. Unfortunately a dealer or mechanic needs to do the CASE relearn procedure for you.
Have you determined if the loss of power issue is resolved at least?
I too would have expected the security light to stay out after the Passlock process.

So far after 24 miles of driving & 30 minutes idling in driveway the truck hasn't quit... Doing the crank relearn hopefully this AM on way to work as time vs distance cut it short last night! Thank you for responding!

 

[Kenzen]

(fingers crossed...)

 

[desgrunner]

(fingers crossed...)

Had to find a longer stretch of highway to do crank sensor relearn... Called company that I got PCM from to confirm the procedure as I was unclear how to start... First, unhook battery and restart? First, clear all the codes? Etc. They just said "Take off and go! So, onto to the highway I went... Went through procedure, the truckers didn't like that I went 45MPH at times! Finished and hoping for a "miracle" I pulled off for gasoline and tried to erase the crankshaft and vapor canister codes... No such luck! I ran the truck another 12 miles home and one good thing is it never shut off! But, still the codes... I ordered the vapor canister solenoid this morning hoping this clears that code. I guess I'm at the point after changing this to go to a repair shop that supports the "big diagnostic" tester! I'm sure they'll be shocked how much pleasure I've had in this... This is why in 1988 I got out of wrenching (one of 2 line mechanics) at a GM "all" 5 lines (Chevy, Buick,Pontiac, Oldsmobile,Cadillac) dealership... You didn't fix anything you just started replacing! Anyway, and long shots on this "truck in a million" is appreciated...

 

[desgrunner]

(fingers crossed...)

Finally received new EVAP vent valve and installed in the "teens" weather we have been having here in NW Ohio in driveway... I also "washed out" the carbon canister as I seen was "doable" just because I was there... Man, it was dirty! Yes, some black was brokedown carbon from internal and some extruded carbon pellets also came out... It says to replace if pellets fall out, but I'm chancing this for now... Went very well as my wifey crawled under truck for an "extra set of hands" to remove lines... Her "1st time" under a vehicle and maybe her last! I "cooked" the canister in our oven at 200 for 15 minutes and re-installed... I had the neg. battery cable unhooked and there again was "no relearn" format! I was down for about 2 hours... WHy doesn't it go through the procedure? The truck started right up! I drove for about 15 miles and called it a day... I installed my code reader and the only code left is the crankshaft position sensor which I could not delete... The over-the-road procedure really I don't think works! The truck runs beautiful & fuel economy for the past week has been good, but I still have the PASSLOCK and engine light on... The PCM rebuilder does say to "if" the crankshaft sensor light doesn't "clear" then go to the next level (a shop with a "scanner" PC...) I guess that makes me ask "What can they do?" Do they over-ride the code and reset it? Will theoretically my PASSLOCK & engine lights go off? Any help is appreciated and what a "journey" this has been... I know this thread will help others! You guys are great!

 

[desgrunner]

P0315 is common after a replacement of the PCM. Unfortunately a dealer or mechanic needs to do the CASE relearn procedure for you.
Have you determined if the loss of power issue is resolved at least?
I too would have expected the security light to stay out after the Passlock process.

Finally received new EVAP vent valve and installed in the "teens" weather we have been having here in NW Ohio in driveway... I also "washed out" the carbon canister as I seen was "doable" just because I was there... Man, it was dirty! Yes, some black was brokedown carbon from internal and some extruded carbon pellets also came out... It says to replace if pellets fall out, but I'm chancing this for now... Went very well as my wifey crawled under truck for an "extra set of hands" to remove lines... Her "1st time" under a vehicle and maybe her last! I "cooked" the canister in our oven at 200 for 15 minutes and re-installed... I had the neg. battery cable unhooked and there again was "no relearn" format! I was down for about 2 hours... WHy doesn't it go through the procedure? The truck started right up! I drove for about 15 miles and called it a day... I installed my code reader and the only code left is the crankshaft position sensor which I could not delete... The over-the-road procedure really I don't think works! The truck runs beautiful & fuel economy for the past week has been good, but I still have the PASSLOCK and engine light on... The PCM rebuilder does say to "if" the crankshaft sensor light doesn't "clear" then go to the next level (a shop with a "scanner" PC...) I guess that makes me ask "What can they do?" Do they over-ride the code and reset it? Will theoretically my PASSLOCK & engine lights go off? Any help is appreciated and what a "journey" this has been... I know this thread will help others! You guys are great!

 

[Kenzen]

They'll run it through the proper relearn. If you have remote locks, now a the time to have them learned as well.

 

[desgrunner]

They'll run it through the proper relearn. If you have remote locks, now a the time to have them learned as well.

Well... I made the dealership and for $75.02 they did the relearn and all lights out! FINALLY...Took them less than 30 minutes and their labor rate is $105/hr. Lasted a few days then the code for coolant issues came on... I have noticed that my heater is longer getting to temp, but it has been in the negative digits here. I'll probably flush and buy into a new thermostat for this 2.8 soon. Was able to delete code with my hand held unit... Anything "directly" engine related (non emissions) has to be relearned at dealer is what they said. Thanks Guys its been a long expensive journey...

 

[RLTherio]

Great to hear that you got it cleared up. In regards to changing your thermostat, it comes with the housing as well. Be careful not to break the two 8mm bolts as I did and trying to remove the broken stud is not located in the easiest place to get to. I had to have my truck towed to a repair shop.

 

[Kenzen]

Yahoo!!!!!! Painful, but you should be in good shape now. The thermostat isn't a fun job either, but take the opportunity for the flush, use the right coolant, and you'll be good - this is predictable and straight-forward, and the flush/coolant is a required maintenance item anyway.

 

[Dragon08]

Glad you are running, and that the dealer treated you well. You think your thermostat is stuck open? Way better than closed! It happens though.

 

[tooldtocare60]

I am a resent joiner to this site,mechanic for 45 years, I joined because I have gotten some really good advice here, I too have faught the po449(intermittant) for years finally found it, my truck is a 05 canyon z71 crew cab 3.5 4x4, never been to the stealership but yet had a wiring splice near middle of frame drivers side(I bought the truck brand new), white wire to pcm was burned into due to a ground slice in same spot(wires had gotten very hot???), also the orange wire was broken at the connection right below the battery on the fender well(was showing good until moved,(broken inside insulation), fixed those wires ,code gone ,cleared and ok!Tried all the known fixed to no avail, for sure electrical issue, for sure!!!!