Camshaft Timing Sensor

red88gt · #1 10-19-2005, 08:02 AM

Stopped in at the local Autozone because my service engine soon light was on. Last time it was because the gas cap was loose & I was expecting this one to possibly be an emission sensor as it is running fine. Anyway, the guy puts the scanner on it & tells me it says camshaft timing sensor but he has no idea what that means. Anyone experienced this ? It runs fine. I guess I should check it out in a service manual but I thought I'd ask here first. Thanks.

GMMerlin · #2 10-20-2005, 07:43 PM

What was the code P0013 or P0014?
This is for the Camshaft Position Actuator Solenoid.

The cam phasing system is a hydraulically actuated phase shifting mechanism. The powertrain control module (PCM) supplies the ignition positive driver and ground circuits. A pulse width modulated (PWM) driver controls the amount that the camshaft actuator solenoid assembly advances or retards the exhaust camshaft. The exhaust camshaft is commanded to a maximum retard position of 25 degrees. When the exhaust camshaft is retarded at the maximum rate, the duty cycle of the signal is at 100 percent. The maximum advance rate has a 0 percent duty cycle. Other than when the camshaft is at full advance, a 50 percent duty cycle is used to maintain a steady retard angle.

The driver has the ability to detect an electrical malfunction in the ignition positive or ground circuit. If an electrical malfunction occurs, the driver signals the PCM to set this diagnostic trouble code (DTC).

I wouldn't expect an Autozone parts guy to have any idea what emission codes mean...it's like going to McDonalds and asking for a Whopper

ScarabEpic22 · #3 10-20-2005, 10:14 PM

Mickey Ds and asking for a Whopper, thats good GMMerilin!!

No harm ment, I just had to laugh at it!

red88gt · #4 10-21-2005, 12:21 PM

Thanks for the reply, GM Merlin. It seems that you're one of the few around who knows anything about this system. I read more about it in one of the GM Tech Bulletins & was pretty amazed. Anyway, it's my wifes car & it seems that she was pretty far away from the last oil change & never checks the oil inbetween (I know that's really my job) so the oil was low. When I drove it, on hard acceleration the oil pressure would drop & the check guages light would come on indicating low pressure. I added 4 quarts of oil to bring it up to full. I'm thinking that this being a hydralic system, the control valve and/or phaser didn't have the oil pressure they needed setting off a code when they couldn't move the cam as they were suposed to. Good therory or totally off base ? It seems to run just fine. The bigger question is where did 4 quarts of oil go in 12,000 miles ? No leaks that I can find.
Can I just disconnect the battery to clear the code & see if it comes back ?

maxwedge · #5 10-21-2005, 03:57 PM

Maybe someone didn't put the proper 7 qts in to begin with, you went 12k on the oil, and didn't check it, you wouldn't suddenly loose 4 qts. GMMerlin, great tech description as usual, BTW I replaced the cp actuator for an oil leak into the connector.

ScarabEpic22 · #6 10-21-2005, 05:46 PM

You lost 4qts??!!! Holy crap, I hope your TB doesnt have any problem coming up because of this, thats pretty scary. I agree with maxwedge, there is pretty much no way the 4.2L I6 can burn 4qts, so either it wasnt completely filled, you are leaking majorly, or your engine has a very serious problem. My 02 with now 55,500mi has never burned oil, never had to top it off. I do my own oil changes, and always drain close to the 7qts (actually drain about 6.5 + filter).

red88gt · #7 10-21-2005, 06:57 PM

I drove it tonight & all seems fine. The check engine light even went off by itself ! Like I said, it runs fine & there's no leaks that I can see. I changed the oil myself this last time & I'm positive that I put 7 quarts in. The reason I'm so positive is that the last time the oil was changed, I checked it not too long after & found it at least two quarts low. I thought that they didn't fill it completely at the oil change place but I'm not so sure now. It doesn't smoke not even a puff at start up, so were's it going ?

maxwedge · #8 10-21-2005, 07:23 PM

3k a qt is considered normal for most cars/trucks. But I have to tell you I've gone 6k in my 2002 TB and it is less than 1/2 qt low and anecdotal evidence says this is not an engine that uses oil. If you are burning it,then you are burning it. Maybe if you drove 80 mph for a 100 miles everday, but with no leaks there is really nothing you are going to do here.

GMMerlin · #9 10-22-2005, 07:15 AM

Quote:

Originally Posted by red88gt

I drove it tonight & all seems fine. The check engine light even went off by itself ! Like I said, it runs fine & there's no leaks that I can see. I changed the oil myself this last time & I'm positive that I put 7 quarts in. The reason I'm so positive is that the last time the oil was changed, I checked it not too long after & found it at least two quarts low. I thought that they didn't fill it completely at the oil change place but I'm not so sure now. It doesn't smoke not even a puff at start up, so were's it going ?

1 qt per 2000 miles is the maximum oil useage for a GM vehicle.
Low oil pressure or lack of maintenance will cause problems with the actuator.
The system works hydraulically so it needs the oil.
It is not uncommon to see these trucks come in with low oil levels..most people don't realize these things need 7 qts.

ScarabEpic22 · #10 10-23-2005, 04:44 AM

Yea, 7qts is a lot. I had to double and then triple take on the owners manual the first time I changed the oil!

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