P0017 Code: Crankshaft–Exhaust Camshaft Correlation, Bank 1 (Chevrolet Guide)

P0017 is "Crankshaft Position – Camshaft Position Correlation, Bank 1 Sensor B." On GM's overhead-cam engines, Sensor B is the exhaust camshaft, so P0017 means the exhaust cam signal on bank 1 is not arriving where the engine computer expects it relative to the crankshaft. On the Chevy 3.6L V6 that usually points to timing chain stretch, and GM's bulletin on that repair says something most shops ignore: do not replace the guides, sprockets or cam actuators unless they are actually worn. But P0017 is not always a chain. GM has documented three different ways a reluctor wheel slips on Chevy engines and sets this code on an engine that is timed correctly.

What Does P0017 Mean?

The engine computer watches two kinds of signals: a toothed reluctor on the crankshaft and toothed reluctors on each camshaft. Because the chain (or belt) ties them together, every cam pulse should arrive at a known crankshaft angle. GM's monitor tables give the window: roughly 10 crank degrees early to 11–13 crank degrees late, depending on the year.

When the exhaust cam signal on bank 1 drifts outside that window, P0017 sets. Something has moved between the crankshaft and that camshaft — or between a camshaft and its own reluctor wheel.

That is why this is a correlation code. It does not mean either sensor is bad. Both sensors may be reporting accurately; they simply disagree with where the timing should be.

Why Sensor B Is the Exhaust Cam

The generic code wording ("Sensor B") hides the most useful fact. On GM dual-overhead-cam engines, "A" is the intake cam and "B" is the exhaust cam. GM's own bulletins write it plainly as "CKP/Exhaust CMP Correlation."

The pairs look like this:

On a four-cylinder there is only bank 1. On the 3.6L V6, GM identifies the banks from the flywheel end: the right bank holds cylinders 1-3-5. In a longitudinal installation (Camaro, Colorado) that is the passenger side. In a transverse installation (Traverse, Equinox V6, Impala, Malibu V6) the engine is turned sideways, and bank 1 sits toward the firewall.

The 3.6L V6 and Timing Chain Stretch

GM's 3.6L "High Feature" V6 — in the Traverse, Equinox, Malibu, Camaro, Impala and Colorado — has a primary chain plus two secondary chains driven through idler sprockets. As the chains wear they lengthen, the cams fall progressively late, and the engine starts setting correlation codes: often P0008, P0016, P0017, P0018 and P0019 in some combination.

GM's bulletin family 12-06-01-009 is the repair document. It covers 2007–2012 3.6L engines and is unusually specific about what not to replace:

• Install a timing chain kit. GM kits 12650230 (2007), 12650231 (2008–2012 LY7/LP1) and 12651450 (2008–2012 LLT/LF1/LFX/LFW).
• Do not replace the idler sprockets, cam actuator gears, crankshaft gear or guides unless a guide's wear block is worn through into the base material.
• Fit camshaft thrust washers on engines built before June 5, 2009 with first-design cam caps.
• Update the Oil Life Monitor calibration. GM linked chain wear to extended oil change intervals and shortened the monitor.

That last point tells you the root cause. On these engines, chain wear and oil change intervals are closely connected. A 3.6L that has had its chains replaced will wear the new ones the same way if the oil service stays the same.

Our timing chain replacement guide covers the job itself.

When It Isn't the Chain: Slipped Reluctors

Here is the expensive mistake GM has documented three times on Chevrolet engines: P0017 on an engine whose chain is fine, because the reluctor wheel the sensor reads has moved.

3.6L V6 — crankshaft reluctor (PIP3423). The crank reluctor is pressed onto the back of the crankshaft. If service information does not find the cause of the correlation codes and the chains are tight, GM's procedure is to look at the reluctor through the crank sensor hole with a borescope. The specification is 25–26 mm from the end of the machined crank throw to the open space on the reluctor (about 3.5 teeth). If it has slipped, the fix is a crankshaft — not a chain kit.

2.0L/2.2L/2.4L Ecotec — camshaft reluctor (PIP4548F). Covers 2010–2016 Equinox, 2007–2013 Malibu, Cobalt, HHR, Captiva and the 2014 Impala. The cam reluctor is a press fit with no key and can spin on the camshaft from heat. GM's title is pointed: "MIL On With DTC P0016 And/Or P0017 Setting On A Properly Timed Engine." On the LE5, with the cam at maximum lift the reluctor should sit flush and parallel with the cam cover gasket surface. If it does not, the camshaft is replaced.

1.4T, 1.5T and 1.4L — exhaust camshaft reluctor (21-NA-268). Covers 2016–2019 Cruze, 2018–2021 Equinox, 2016–2021 Malibu, Spark and Trax. Symptoms include a crank-no-start or extended crank with P0014, P0017, P0365 and/or P0366. The exhaust cam reluctor can be out of phase; GM's check lines up a mark on the cam hex with the reluctor tang. The repair is an exhaust camshaft and vacuum pump.

The lesson is the same in all three: a timing chain kit does not fix a slipped reluctor, and P0017 alone does not prove the chain is stretched.

Oil and the 2.4L

The 2.4L (LAF/LEA) in 2010–2013 Equinox and Captiva had a well-documented oil consumption problem. GM bulletin 13-06-01-003H covers an oil consumption test and, where consumption exceeds 1 quart in 2,000 miles, a piston and ring kit. The bulletin also notes two things that matter for cam codes: running low on oil can cause cam actuator noise, and the dipstick may show no oil until the engine is about 1.25 quarts low.

A 2.4L that has run low on oil for months will wear its timing components and starve its phasers. GM's coverage parts lists for these engines specify dexos1 5W-30. We did not find a GM bulletin that ties 2.4L P0017 directly to primary chain stretch — that link comes from field experience — but low oil on this engine is a reliable way to end up with cam codes of every kind.

Symptoms of P0017

• Check engine light on
• Rattle at cold start, especially for the first few seconds (typical of chain wear)
• Rough idle or reduced power
• Extended cranking or a crank-no-start on the 1.4T/1.5T exhaust reluctor condition
• Poorer fuel economy
• P0008, P0016, P0018 or P0019 alongside on the 3.6L

Causes and How to Confirm Each

How Is P0017 Diagnosed?

1. Record every cam and crank code. On the 3.6L, a cluster of correlation codes points strongly at chains; a lone P0017 needs more proof.
2. Check the oil level and history. On a 2.4L, remember the dipstick may read empty only at 1.25 quarts low.
3. Look at cam/crank variation data with a GM-capable scan tool and compare to the service limit.
4. Listen at cold start for a chain rattle.
5. Inspect chains, tensioners and guides if the data supports stretch. On the 3.6L follow 12-06-01-009 — chain kit, not every sprocket and guide.
6. If the chains are tight, check the reluctors using the GM procedure for your engine (PIP3423, PIP4548F or 21-NA-268).
7. Check exhaust phaser operation and any P0013/P0014.
8. After any chain repair, update the oil life monitor where the bulletin calls for it and shorten your oil service interval.

Parts and Cost

GM Documents That Name P0017

Have a dealer check your VIN against current bulletins and coverages rather than relying on any article, including this one.

What Other P0017 Pages Get Wrong

• "Replace the cam sensor first." A correlation code means the sensors disagree with the timing, not that a sensor is dead. A failed sensor usually sets P0365/P0366.
• "Replace every guide, sprocket and phaser." GM's 3.6L bulletin explicitly says not to unless they are worn through.
• Calling Sensor B the intake cam. On GM DOHC engines it is the exhaust cam.
• Treating P0017 as proof of a stretched chain. GM has documented slipped reluctors on the 3.6L crank, the Ecotec cam and the 1.4T/1.5T exhaust cam — all setting P0017 on engines in time.
• Citing a GM bulletin for "2.4L P0017 = chain stretch." The GM 2.4L P0016/P0017 bulletin is about a spun cam reluctor on a properly timed engine.
• Forgetting the oil. GM shortened the 3.6L oil life monitor as part of the chain repair. Put the new chains on the old oil schedule and you will be back.

Frequently Asked Questions

Is P0017 serious?

It can be. If the cause is chain stretch, the chains keep wearing until the engine runs poorly or, in the worst case, jumps timing. If it is a slipped reluctor, the engine may become hard to start. Either way, diagnose it rather than driving on it indefinitely.

Does P0017 always mean a timing chain on a Chevy 3.6L?

It is the most common cause, especially when P0008, P0016, P0018 or P0019 are also set. But GM's PIP3423 covers a slipped crankshaft reluctor on the same engine that sets the same codes with tight chains. Confirm before committing to a chain job.

What is Sensor B?

On GM dual-overhead-cam engines, Sensor B is the exhaust camshaft position sensor. P0017 is bank 1 exhaust; P0016 is bank 1 intake.

Can low oil cause P0017?

Indirectly, yes. Low and old oil accelerates chain wear and affects how phasers hold position. On the 2.4L, GM notes the dipstick may not show low until about 1.25 quarts down — so check it often.

What oil should I use to protect the timing chain?

The dexos-approved grade your owner's manual specifies, changed on time or sooner. GM's 2.4L coverage parts lists specify dexos1 5W-30. For the 3.6L, GM updated the oil life monitor to shorten intervals as part of the chain repair.

Can I clear P0017 and keep driving?

It will return if the cause is mechanical, and stretched chains do not get better. Clearing it is only useful to confirm a repair.