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2004 chevy trailblazer_lt
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First post here. My 2004 TB has 106K miles and is sometimes running rough at idle or near idle. Seems to happen intermittently and only when at full operating temperature. It is throwing DTC codes P0014 and P0016. I replaced both the Cam Position Sensor and Cam Position Actuator Solenoid then my mechanic performed the "relearn" procedure and did an engine oil flush. The old CPAS looked somewhat dirty but no screens were missing. After all this, there is no improvement and the DTC codes are still being thrown. My mechanic says the exhaust cam phaser under the valve cover needs replaced. Does this sound legitimate? At $700 I want to be sure. What would be physically wrong with the exhaust cam phaser? Should the timing chain be replaced too?
 

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2002 chevy trailblazer_lt
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ill check all the wiring first before jump into anything once you have all good connection then make yourself a jumper cable with fuse on it and jump B+ and the CMP actuator control circuit at the solenoid and jump the low reference of the camshaft position actuator solenoid to ground you should see the pin inside move if not replace CMP

and for code P0014
you need tech 2
scan it check all the module see there any missing communication or any U code
 

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2006 chevy trailblazer_lt
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70TA, I am having this exact same issue. My shop told me the phaser is sticking in full advance or retard mode. They can get the phaser to move but it sticks in one of those two positions. I have heard that dirty engine oil can cause this issue, but doesn't seem to be a factor in my situation. Good luck!
 

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ill check all the wiring first before jump into anything once you have all good connection then make yourself a jumper cable with fuse on it and jump B+ and the CMP actuator control circuit at the solenoid and jump the low reference of the camshaft position actuator solenoid to ground you should see the pin inside move if not replace CMP

and for code P0014
you need tech 2
scan it check all the module see there any missing communication or any U code
Any suggestions? 2002 trailblazer new crank,rods,pistons,oil pump, valves, timing set with new phaser, after installing the new build it started up with the first turn of the key. No ticking or rattling. All sensors are also new. After 1 hour on the engine I'm getting a p0014 code as if the actuator isn't working correctly or not at all. Took it to the shop where the mechanic told me the phaser was bad but it's new. Everything is new. With this being my first engine build that's in my company vehicle what steps do I need to take at this point to verify that the work is legitimate. It seems electronic to me and this particular mechanic said he couldn't do the crank sensor relearn because the phaser was bad or the oil gallery was sludged up. The engin has less than 2 hours on it and everything is new.
55260
20200610_201824.jpg

 

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2002 chevy trailblazer_lt
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I will assume you got the right phaser for your year, I understand there are more than one flavor.

Do you have a scanner that reads live data? Or even a $15 bluetooth chinese clone of the elm327? (With Torque smartphone app can read cam phaser operation with the proper setup)
 

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Thank you for your help. I do have a scanner that reads live data. so I'm guessing that I'm looking to see if the actuator solenoid is getting the signal from the pcm that would be displayed as different numerical values as the throttle opened? and if it is getting the signal and iv tested the actuator solenoid and its working then its the phaser?
 

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Well depending on what values your scanner shows. I would be looking to confirm signal to the solenoid ( it's a pwm so display as percentage), requested phaser angle, actual phaser angle, and variance. I have no idea what parameters cause the desired angle from the PCM but I think it is not a direct correlation with RPM (not aligned with throttle opening).

Looking at the details of the code you have you need to be seeing the variance between commanded and actual angle. By observing the variance you may be able to see if the phaser is failing to get to the commanded angle or is it sticking and failing to return from that angle.

I also can display the crank and camshaft pulse counts as seen in the picture but the resolution is not good as the pid scanning frequency and other things make the readout kind of hit & miss.

Screenshot_20200618-100308~01.png


20190822_211305 (1).png
 
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