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2011-2016 Cruze 1.4 PCV Valve Cover/Intake Manifold Issues

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2011-2016 Cruze 1.4L PCV Valve Cover/Intake Manifold Issues

I made a video to help better explain how this whole PCV system works to supplement this article.

I find myself having to explain this issue to someone almost daily, so in the interest of brevity, I'm creating a thread specifically for people to reference quickly if they have an issue.

The Cruze 1.4L Turbo engine has a terrible PCV check valve design that afflicts 100% of cars I have come across. It's not a matter of if, but when, it will fail. There are three primary components to this system that frequently fail: the PCV regulator diaphragm (some people call it a check valve) on the valve cover, the check valve in the intake manifold, and the corrugated hose going from the intake manifold to the turbo. We will focus on the first two, which are the most likely failures.

Depending on how long you've had this issue, your vehicle may throw a check engine light with any or all of the following codes (DTCs):

Note: lack of check engine light does not mean everything is operating correctly!

Your vehicle may also exhibit any or all of the following symptoms:
  • Elevated oil consumption
  • Smoke blowing through the tail pipe
  • A hissing sound in the engine bay
  • A rough/stumbling idle
  • Loss of power
  • Reduced fuel economy

Valve Cover
With the engine running, inspect the vent on the PCV regulator diaphragm. The PCV regulator diaphragm has a round non-removable cap on the driver side of the valve cover. Remove the cosmetic cover off of the valve cover:

Underneath, you'll find the cap that covers the PCV regulator diaphragm. If this has failed, the engine will be sucking in air from here, and creating a hissing sound. Place your finger over this hole to cover it. If the engine RPMs change or the hissing stops, the valve cover needs to be replaced.

DON'T STOP THERE! Failure of the valve cover PCV regulator diaphragm may only be a symptom of a greater problem: the PCV check valve in the intake manifold. If the intake manifold PCV check valve has failed and you only replace the valve cover, you will find yourself replacing valve covers every few months not knowing why.

Intake Manifold PCV Check Valve
With the engine off, locate the corrugated hose coming out of the top of the PCV check valve:

With tightly gripped pliers, remove the clip holding the hose off by pulling it out:

Pull the corrugated hose off from the base, taking care not to pull from the hose itself as it may crack or tear. Using a flashlight, look inside the hole. If you are facing the engine bay from the front, there should be an orange/pink/peach nipple/valve on the "back" of that hole that looks like this:

If you don't see that check valve, use q-tips and rubbing alcohol to clean that area and check again. If you still don't see it, this must be addressed.

There's one final part that needs to be checked:

PCV Hose/Valve
In the last section, you need to remove a hose from the intake manifold. That hose has another check valve at the other end of it; at the turbo inlet. To verify its functionality, blow into the hose; it should blow freely. Suck air back through the hose; it should completely block airflow. If it doesn't do either of these, the whole thing needs to be replaced. Those hose also has a tendency to become brittle and crack, at which point it will also need replacing. Be sure to check this hose everywhere if you suspect it is leaking or are hearing a hissing sound in the engine bay.

Repair Solutions
Both of the above components are covered under your powertrain warranty. If your car is still under powertrain warranty, bring your car to the dealer and tell your dealer you are experiencing oil consumption of one quart per 1,000 miles and to reference GM Bulletin PIP5197C.

If the PCV regulator diaphragm on the valve cover has failed, replacement is required and will cost ~$60. Refer to this tutorial for replacing the valve cover. How-To: Replace the Valve/Camshaft Cover (1.4L Turbo)

If the check valve on the intake manifold is missing, you have three options:
1. You can replace the intake manifold with a new one. As of late early 2018, GM is phasing out the intake manifold that ships with all accessories and is selling a bare intake manifold. I don't yet have the part number for that.
2. Dorman has begun releasing an option. However, this option has the same check valve design as the GM manifold, meaning it will be prone to failure and boost leaks, and is not serviceable. The part number is 615-380, but availability is currently limited.
3. You can install one of my Intake Manifold PCV check valve fix kits for as little as $75, which is much cheaper than the Dorman intake (after shipping) while providing you a more robust, leak-free, and durable check valve. My external check valve design allows for easy (doesn't require removal of the intake manifold) servicing and cleaning, and inexpensive replacement. Details are in this thread: GM 1.4L Turbo Intake Manifold PCV Valve Fix Kits

A tutorial for removing the intake manifold is located here: How-To: Remove 2011-2016 Cruze 1.4L Intake Manifold

If the check valve at the turbo inlet has malfunctioned or the hose is cracked, you will need to replace it: ACDelco 25193343 PCV Pipe with Valve

To learn more about this engine's PCV system, refer to the following thread: 2011-2016 Cruze Limited 1.4L PCV System Explained


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Hi Guys, hi @XtremeRevolution.
Great to see such a helpful community!
I recently got a lot of trouble with my Astra J 1.4 T A14NET. After some research in german boards I came across the PCV Fix Kits, now I need some help with diagnostics.
What happened:

Phase 1:
Under heavy load, the display showed "Fahrzeug demnächst warten".
The error log had the entry 'P0299'.
I ignored this error for some time.

Phase 2:
After a longer trip, Oil leaked from the valve cover gasket and the camshaft adjuster gasket, apparently under high pressure. A repair shop fixed this by replacing the to gaskets, but unfortunately I forgot to tell them about the error P0299 and they didn't check the error log.

Phase 3:
On another trip to Italy, the check engine lamp came on. I again checked the error log, this time the entry was
P0171 - System too lean, bank 1
P0106 -

Manifold absolute pressure (MAP) sensor/barometric pressure (BARO) sensor - range/performance problem

P1101 - Mass air flow (MAF) sensor - range/performance problem

I also noticed that the engine was sucking a lot of air through the small hole at the diaphragm inside the valve cover.
The engine ran unsteadily at idle, but quietly under load.
When I covered the hole inside the valve cover, the engine run more smoothly, but after like 15 seconds, a lot of smoke came out of the exhaust.

I stopped covering the hole, the smoke was gone, and I decided to continue driving as it was late in the night and I was already in Italy.

Phase 4:
On my way back, I worried about the engine and tried covering the hole again, but only partly. I hoped I could reduce the amount of air sucked in, so the mix wouldn't be too lean. After a few seconds, the exhaust again blew out a huge amount of smoke, but this time it didn't stop for maybe 30 seconds, so I decided to stop the engine and get the car back home by a towing service.

Right now the car is at a repair shop, but I'd rather try to fix it on my own.
I removed the corrugated hose, and couldn't see the orange thing. But there was really a lot of oil inside, so maybe I should clean it first.

I'm sure the diaphragm in the valve cover is broken, I suspect also the valve inside the intake manifold.
How would you proceed to further diagnose the problem?
Is there any explanation for the huge amount of smoke though the exhaust when covering the hole in the valve cover?

Btw., I already ordered the PCV Fix Kit.
Thanks in advance for your help!
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Are there any tutorials on replacing the valve cover membrane only without destroying the plastic cover?
I've found the membrane as a spare part, but the cover seems to be glued/welded.
The description says it's for the 1.4L valve cover: Ventildeckel Reparatursatz Membran für Chevrolet Cruze Trax 25198874 55573746 | eBay
But I'm skeptical too.
I'll give it a try, can't make things worse.
Where are you located that you're seeing those prices? OEM valve covers here are $65-$80 USD.
Germany: I got a quote from my garage, OEM valve cover without installation 420€ which is the SRP from Opel.
Also found it for 200€ online.
I may try to develop a process that allows one to remove those valve cover diaphragms and replace them cleanly. It would sure help the community if I can figure it out. I'd keep those diaphragms in stock as well.
That would be really helpful.
I ordered the membrane with cap included I mentioned above and will try it as soon as it arrives.
Let me know if you have any ideas especially which glue to use.
My kit arrived a few days ago, way earlier than expected, thanks @XtremeRevolution !
I installed it today and changed the valve cover to a new Dorman.
Actually I wanted to try to change the membrane only, but as the membrane hasn't arrived yet, I decided to use the new cover and try to fix the membrane of the old cover later and keep it as a backup.

For the kit, I needed two attempts to place the clip inside the manifold, so it ended up a little bit messy in there.

I did some testing today, when the engine is not completely hot (even 5 minutes after turning it off), idle is very stuttering, even the gear knob started shaking and engine stopped at a traffic light. Besides that, everything seems fine, no fault codes, no smoke anymore, full performance.
And idle is fine when the engine is hot, so it feels completely different to the idle problems I had before.

What to do next?
I know Andrei had bad experiences with non OEM valve covers, but I doubt that it could be that bad?
Are there any other possible reasons for this behavior?
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Vacuum leak or defective evap purge valve. Did you lose the retaining clip inside the pcv pipe manifold terminal?
No, I didn't lose it. Didn't find the hole, pushed too hard and clip was bent but I got it back out.

How could I test for vacuum leak or defective evap purge valve?
OBD plug is available.

Btw. I tested and cleaned the check valve at turbo inlet.
I think the whole sound changed a bit, but I might be wrong.
I just wanted to check the purge valve, but now even with cold engine idle was very smooth.
Maybe the purge valve is about to get defective and was stuck open when I tried the first time.

Another thing I noticed: I can remove the hose on the left side of the purge valve without removing the green clip, this doesn't feel right, so maybe there could be a leak.
Maybe the first time I tried the purge valve was open on purpose but this leak was causing the problem?

I'll check it as soon as I have rough idle again.
I really appreciate your help!
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Hey guys,
I installed the V3.4 kit about one year ago and everything was fine.
A few days ago I noticed oil leaking from between engine and gearbox, and from the cover on the other side of the engine.
Vacuum on idle is 38 mbar.
I assume over pressure on high rpm, didn't test it yet. This would explain the oil possible being pushed out of the crank seal rings.
Engine is hissing a lot also when I remove the dip stick and starts stuttering. No hissing and no effect when I cover the membrane hole on the cover, so I assume the membrane is good.
I then changed the check valve from the kit, but nothing changed.
There's a small leakage, but maybe already older because it was crusty, at the oil pipe to the turbo.
Do you have any ideas where to look at next? Thanks in advance!

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Today I checked the plug I glued into the intake manifold, I suspected it could have been gone as the glueing process wasn't that easy.
But as far as I can see from above it is still in place, even if it looks a bit messy.
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You may need to clean or replace the PCV valve.
I just measured the crankshaft pressure for higher rpms and it stays at around -35 mbar, which is good as far as I know.
So probably there's no PCV related issue and I'm going to have to replace the crankshaft seal on the gearbox side next.
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