GMC Terrain, Equinox, and SRX Forum banner
1 - 20 of 76 Posts

·
Registered
2012 Equinox LT 2.4l
Joined
·
35 Posts
Discussion Starter · #1 · (Edited)
SOLVED: the car needed a timing chain job and a exhaust position sensor. Long story short: Do not buy non OEM timing components. In my case it was a non OEM cam sensor not being recognized by the ECM.



Hi guys,

Trying to diagnose a p0017 code on my 2012 equinox and checked the wiring to the cam position sensor on the back of the engine.

With the ignition set to acc and the sensor connected the 3 wires are showing middle white as ground, green as 0.72v constant, and yellow as 5v switched (as I pass it infront of metal).

With the sensor disconnected I am getting 5v to the green and yellow and ground appears to be working.

The green is supposed to be showing 12v with ignition on isn't it? Is it possible I have both broken wiring and a dead sensor?

Can I bypass the PCM on the green constant and run it directly to the battery positive or another good acc 12v source?
 

·
Registered
Joined
·
2,848 Posts
I have worked on several cars with the P0017 code and most of the time it is a bad cam pos sensor or wiring.
I'm not telling you to throw parts at this but save yourself some time and start with a new AC/Delco cam pos sensor.
It's not expensive but the alternatives like Engine Control Module or timing chains are.
 

·
Registered
2012 Equinox LT 2.4l
Joined
·
35 Posts
Discussion Starter · #3 ·
I have worked on several cars with the P0017 code and most of the time it is a bad cam pos sensor or wiring.
I'm not telling you to throw parts at this but save yourself some time and start with a new AC/Delco cam pos sensor.
It's not expensive but the alternatives like Engine Control Module or timing chains are.
Well I was going to start with replacing the sensor but thought I'd check the wiring to it first. I'm glad I did because like I say I'm only getting 5v which is why I'm wondering isn't it supposed to be 12v on the green ignition source wire?
 

·
Registered
Joined
·
2,848 Posts
The yellow with black, pin A on the exhaust cam pos sensor, is your 5 volt reference from the ECM.
The dark green, pin C on the exhaust can pos sensor, comes from a pull down resistor in the ECM.
The grey, pin B comes from the sensor and goes to the ECM Ground.
 

·
Registered
2012 Equinox LT 2.4l
Joined
·
35 Posts
Discussion Starter · #5 ·
Before I order the cam position sensor I figured I would check my timing chain for looseness, had a rattle last week and this P0017 code only showed up after I replaced the chain tensioner.

Is this tight enough in your opinion?

Video:

The engine is absolutely filthy but I'm reluctant to clean it since it burns oil and I don't want to ruin what seal the rings have left.
 

·
Registered
Joined
·
2,848 Posts
The ECM will set P0016 or P0017 if the camshaft is greater than 10 degrees advanced or retarded in relation to the crankshaft.
You are probably at that threshold.
Which means a new sensor might still see the 10 degrees variance and keep setting the code.

If you are going to keep it, put in new timing chains, gears, and guides.
If not try a new sensor and trade it.
How many miles on the clock?
 

·
Registered
2012 Equinox LT 2.4l
Joined
·
35 Posts
Discussion Starter · #7 ·
The ECM will set P0016 or P0017 if the camshaft is greater than 10 degrees advanced or retarded in relation to the crankshaft.
You are probably at that threshold.
Which means a new sensor might still see the 10 degrees variance and keep setting the code.

If you are going to keep it, put in new timing chains, gears, and guides.
If not try a new sensor and trade it.
How many miles on the clock?
Thanks Rednox!

We plan to sell it, I would love to fix it first to sell it for a lot more but $400 for all the timing chain kit and sprockets etc is pretty steep. Like you say, I may try the cam sensor and be done with it..

Decisions Decisions!
 

·
Registered
Joined
·
1,157 Posts
How all the sensors work is the PCM uses the 5v as a constant reference voltage. Ground is ground and the sensor feedback (green in your case) is what the PCM uses to monitor / measure the sensors feedback against what it's program wants to see.
Do not put 12v into any sensor circuit, you'll blow up the PCM.
Think of the sensors as a volume control, depending on what each one is monitoring the sensor varies voltage back to the PCM.
 

·
Registered
Joined
·
50 Posts
It could also be the reluctor. My 2014 Terrain had this same code. Turns out one of the times it was low on oil the reluctor moved and wasn't where the sensor expected it to.
 

·
Registered
2012 Equinox LT 2.4l
Joined
·
35 Posts
Discussion Starter · #10 ·
Thats the first time i've seen anyone mention the reluctor but that makes sense, do you know if there's any way to tell whether it's the reluctor or chain before replacing parts?

Good thing I didn't wire up 12v to the cam position sensor! I still find it strange that it drops from 5v to 0.7v on the feed wire when I put the sensor back into the connector. I have another sensor on order will try it first since it's the cheapest easiest solution.

On another note, I also find it interesting it's only throwing code P0017 (exhaust) and not P0016. Maybe the exhaust phaser alone jumped a tooth when I replaced the tensioner and the intake/crank stayed in time? This code only showed up immediately after changing the tensioner.

Even though I'm selling the vehicle I just cant let it beat me, will post here with a solution for others if I get it fixed.
 

·
Registered
2012 Equinox LT 2.4l
Joined
·
35 Posts
Discussion Starter · #11 ·
Completed a timing chain replacement, wasn't as hard as I thought it would be.

Vehicle starts up and idles smooth as butter now, however it's showing the check engine light again. I would check the code but my scanner just died on me, great timing...

I suspect it's the same p0017 code as before, if this is the case does the vehicle just need a crank relearn with a GM tech II tool?

Is it typical need a relearn after a timing chain job?
 

·
Registered
2011 Equinox 1LT V6 3.0L
Joined
·
3,996 Posts
@Derap34 : The “Crankshaft Position System Variation Learn” is DTC P0315. Shop Manual says “any engine repairs which disturb the crankshaft to crankshaft position sensor relationship” (or the sensor replacement).

Maybe drop by a local auto parts store to borrow their code reader?
 

·
Registered
2012 Equinox LT 2.4l
Joined
·
35 Posts
Discussion Starter · #13 ·
@Derap34 : The “Crankshaft Position System Variation Learn” is DTC P0315. Shop Manual says “any engine repairs which disturb the crankshaft to crankshaft position sensor relationship” (or the sensor replacement).

Maybe drop by a local auto parts store to borrow their code reader?
I borrowed a code reader at work, it's sending P0017 again. I've tried clearing it but it keeps coming back.

The car runs flawlessly and has a smooth idle unlike before the timing chain job.

Any ideas?
Thanks for your help
 

·
Registered
Joined
·
779 Posts
I would try the actuators first they are very easy... Next your looking at the phasers themselves on the camshaft worst case scenario it's the reluctor or even timing chain improperly installed.
 

·
Registered
2012 Equinox LT 2.4l
Joined
·
35 Posts
Discussion Starter · #15 ·
I would try the actuators first they are very easy... Next your looking at the phasers themselves on the camshaft worst case scenario it's the reluctor or even timing chain improperly installed.
Sadly they've already been replaced, (the actuators aka solenoids) I've also replaced the exhaust cam position sensor and completed a timing chain job.

The only part left to replace would be the exhaust cam phaser but if it was bad would the engine not run rough?
 

·
Registered
Joined
·
779 Posts
The cam phasers are supposed to lock into place when you shut the car off like lock the timing gear to the cam through a pin inside if they don't, that code might come up. Did you use acdelco brand Solenoids? Just trying to narrow it down a little. Does the code come on immediately after clearing or after a few times of driving?
 

·
Registered
2012 Equinox LT 2.4l
Joined
·
35 Posts
Discussion Starter · #18 ·
The cam phasers are supposed to lock into place when you shut the car off like lock the timing gear to the cam through a pin inside if they don't, that code might come up. Did you use acdelco brand Solenoids? Just trying to narrow it down a little. Does the code come on immediately after clearing or after a few times of driving?
I used cheaper solenoids from Amazon, the ohm resistance tested good before I installed them though.

The code shows up on the code reader immediately after erasing it, after turning the car off and on a few times the check engine light will come back on.
 

·
Registered
Joined
·
779 Posts
Immediately comes on after starting just idling I would say it's internal. You should be able to drive the car fine but without vvt working properly.
 

·
Registered
2012 Equinox LT 2.4l
Joined
·
35 Posts
Discussion Starter · #20 ·
Immediately comes on after starting just idling I would say it's internal. You should be able to drive the car fine but without vvt working properly.
Yeah the vehicle seems to run fine, just would be nice to clear this check engine light. What do you mean by it being internal? It's not fixable?
 
1 - 20 of 76 Posts
Top