CriticalCommonEngine

Nissan Patrol: ZD30 3.0 diesel 'grenade' — melted pistons from overboost and overfuelling

ZD30 3.0 diesel 'grenade' — melted pistons from overboost and overfuelling is a common engine fault on the Nissan Patrol on the 2000–2007 cars, and we rate it critical. Putting it right costs $6,000 to $15,000 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 48 documented faults on the Nissan Patrol.

Vehicle: Nissan Patrol
Engine: ZD30
Years: 2000–2007
Fuel: diesel
System: Engine

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

All Nissan Patrol faults48 documented faults on this model

What you are looking at

No photograph available

We do not hold a verified photograph of the Fuel rail yet. We would rather show none than show a picture of a different part.

What goes wrong

The direct-injection ZD30 in GU Patrols earned the nickname 'the grenade' for sudden catastrophic failures: a fouled MAF sensor causes overfuelling and dangerous exhaust temperatures, factory boost control allows spikes to 20-25 psi, and Nissan originally published the oil capacity as 6 litres when the engine actually needs 8.3 — a combination that melts and cracks pistons without warning. The known protection package (MAF cleaning every 10,000 km, Dawes/needle valve boost control, boost and EGT gauges, catch can, free-flowing exhaust) largely tames it, and the 2007-on common-rail ZD30CRD is much improved. An unmodified early ZD30 with no gauges is a gamble.

What you would notice

Sudden loss of power with white/grey smoke (piston failure)
Excessive black smoke under load beforehand
Boost spiking past 18 psi on a gauge
High oil consumption or oil surge on inclines

How to check it

Where to look. Engine internals; check the A-pillar/dash for gauges and the intake plumbing for a Dawes valve and catch can

Look for the protection mods: a boost gauge and EGT gauge on the pillar, a Dawes valve in the boost line, an oil catch can, and an aftermarket exhaust — their presence signals an owner who understood the engine.
Ask what oil capacity the owner uses (the right answer is around 8 litres, not 6).
A compression test before purchase is strongly advised on any unmodified example.

Parts involved: Fuel rail.

What it costs to put right

$6,000 to $15,000 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 it got boost and EGT gauges and a Dawes valve fitted?”
“How often is the MAF sensor cleaned?”
“Has the engine ever been rebuilt, and is there an invoice?”

Now check the Nissan Patrol 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.

CarsGuide 'ZD30 Patrol: Your guide to the Nissan Patrol ZD30 engine'
patrol4x4.com 'ZD30 Grenade - WARNING SIGNS' thread
nissanpatrol.com.au '3.0lt GU Patrols - Grenade Facts' thread
Denco Diesel and Turbo ZD30 turbo service bulletin
GC Patrols 'ZD30 Engine Failure Protection (NADS kit)'

Nissan Patrol buyer questions

Is zd30 3.0 diesel 'grenade' — melted pistons from overboost and overfuelling serious on a Nissan Patrol?

We rate it critical and common on the Nissan Patrol. The direct-injection ZD30 in GU Patrols earned the nickname 'the grenade' for sudden catastrophic failures: a fouled MAF sensor causes overfuelling and dangerous exhaust temperatures, factory boost control allows spikes to 20-25 psi, and Nissan originally published the oil capacity as 6 litres when the engine actually needs 8.3 — a combination that melts and cracks pistons without warning. The known protection package (MAF cleaning every 10,000 km, Dawes/needle valve boost control, boost and EGT gauges, catch can, free-flowing exhaust) largely tames it, and the 2007-on common-rail ZD30CRD is much improved. An unmodified early ZD30 with no gauges is a gamble.

How much does it cost to fix on a Nissan Patrol?

$6,000 to $15,000 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 Nissan Patrol years are affected?

Our research records this fault on the 2000–2007 Nissan Patrol. 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?

Look for the protection mods: a boost gauge and EGT gauge on the pillar, a Dawes valve in the boost line, an oil catch can, and an aftermarket exhaust — their presence signals an owner who understood the engine. Ask what oil capacity the owner uses (the right answer is around 8 litres, not 6). A compression test before purchase is strongly advised on any unmodified example. Look here: Engine internals; check the A-pillar/dash for gauges and the intake plumbing for a Dawes valve and catch can