MajorCommonEngine

Holden Trax: PCV diaphragm failure in the valve cover, oil burning and whistle (1.4 turbo LUJ/A14NET, TJ Trax)

PCV diaphragm failure in the valve cover, oil burning and whistle (1.4 turbo LUJ/A14NET, TJ Trax) is a common engine fault on the Holden Trax on the 2013–2018 cars, and we rate it major. Putting it right costs $400 to $900 at New Zealand independent workshop rates. Below is what goes wrong, the symptoms to notice on a test drive, where to look, and what to ask the seller before you hand over any money. It is one of 8 documented faults on the Holden Trax.

Vehicle: Holden Trax
Engine: 1.4L
Years: 2013–2018
Fuel: petrol
System: Engine

This page covers the Holden Trax as a model. Some faults only affect particular engines or build years — enter a plate below to narrow the list to one car.

All Holden Trax faults8 documented faults on this model

What you are looking at

No photograph available

We do not hold a verified photograph of the Rocker / valve cover or Turbocharger or PCV / oil separator yet. We would rather show none than show a picture of a different part.

What goes wrong

The 1.4 litre turbo petrol (LUJ, also known as A14NET) in the 2013 to 2018 TJ Trax has its crankcase ventilation (PCV) pressure regulator as a rubber diaphragm built into the plastic camshaft (valve) cover, and tearing of that diaphragm is a known issue. A torn diaphragm causes a vacuum leak that shows as a whistle or hiss once warm, a rough idle, lean running fault codes and oil being drawn in and burned. GM issued a service bulletin for the Trax that replaces the whole camshaft cover, because the diaphragm is not sold separately. No recall or extended warranty applies.

What you would notice

Whistle or hiss from the engine once warm
Rough or hunting idle
Check engine light (lean codes such as P0171)
Oil consumption or oil mist on top of the engine

How to check it

Where to look. Top of engine, plastic camshaft (valve) cover

With the engine warm and idling, listen at the top of the engine for a whistle or hiss.
Look around the top of the engine and the camshaft cover for oil mist or wetness.
Check the dipstick for a low level and ask about oil top-ups and check engine lights.
Ask whether the camshaft cover has been replaced.
If a workshop inspection is possible: with the engine idling, cover the small vent on the PCV diaphragm cover on the camshaft cover; if the whistle stops or the idle smooths out, the diaphragm has failed.
Scan for P0171, P0106, P0507 and P1101.

Parts involved: Rocker / valve cover, Turbocharger, PCV / oil separator.

What it costs to put right

$400 to $900 at New Zealand independent workshop rates. That is for this job on its own, not for the car.

An estimate, in NZD, for the repair as normally carried out. What a specific car costs depends on which part has failed and what it damaged on the way — treat this as the floor for a negotiation, not a quote.

Ask the seller

“Has the camshaft (valve) cover been replaced?”
“Does it whistle or hiss at idle once warm?”
“Has a check engine light come on, and which codes were found?”

Now check the Holden Trax you are actually looking at

Everything above is true of the model, and it is free. What it does not tell you is whether THIS car has been looked after: its odometer history and whether the reading has ever gone backwards, whether there is still money owing on it, whether it has been reported stolen, how many owners it has had and what it is really worth today. That comes from the official records for that plate. Enter the plate for the free details, or get the full history and a market valuation from $13.49.

Not sure what you would be paying for? See what a full KickTyres check includes.

Where this comes from

The failure described above is documented in the sources below. The inspection instructions and the cost estimate are KickTyres’ own interpretation of them.

Holden Trax buyer questions

Is pcv diaphragm failure in the valve cover, oil burning and whistle (1.4 turbo luj/a14net, tj trax) serious on a Holden Trax?

We rate it major and common on the Holden Trax. The 1.4 litre turbo petrol (LUJ, also known as A14NET) in the 2013 to 2018 TJ Trax has its crankcase ventilation (PCV) pressure regulator as a rubber diaphragm built into the plastic camshaft (valve) cover, and tearing of that diaphragm is a known issue. A torn diaphragm causes a vacuum leak that shows as a whistle or hiss once warm, a rough idle, lean running fault codes and oil being drawn in and burned. GM issued a service bulletin for the Trax that replaces the whole camshaft cover, because the diaphragm is not sold separately. No recall or extended warranty applies.

How much does it cost to fix on a Holden Trax?

$400 to $900 at New Zealand independent workshop rates. That figure is for this job on its own. A car showing the symptoms on this page is usually worth either walking away from or negotiating down by at least the repair figure.

Which Holden Trax years are affected?

Our research records this fault on the 2013–2018 Holden Trax. Build dates move around, especially on imported cars, so treat the range as the years to look hardest at rather than a guarantee either way. The official records tell you the exact build and first registration date for the car in front of you.

How do I check for it before I buy?

With the engine warm and idling, listen at the top of the engine for a whistle or hiss. Look around the top of the engine and the camshaft cover for oil mist or wetness. Check the dipstick for a low level and ask about oil top-ups and check engine lights. Ask whether the camshaft cover has been replaced. If a workshop inspection is possible: with the engine idling, cover the small vent on the PCV diaphragm cover on the camshaft cover; if the whistle stops or the idle smooths out, the diaphragm has failed. Scan for P0171, P0106, P0507 and P1101. Look here: Top of engine, plastic camshaft (valve) cover