Missfire under load

[trickydicky]

Strange power loss when driving hard under load in third gear only.
goes like hell in 2nd and 1st, but when I change up it starts to miss a beat.
If I blip the throttle and back off slightly and come back on with the power it will come back up but still with the odd gap in power.
I've changed fuel filter to Nissan one, cleaned MAF sensor and ran ecutalk on laptop. No fault codes reported and MAF voltage goes up to 3.7v no trouble.
Car runs fine in top gear cruising at 60 70 mph no trouble.
Its like limp mode is coming on briefly as its sensing overboost but thought that this would happen in 2nd gear as well, not just in 3rd. Also wouldn't it show a fault code?
Does anyone think it might be an injector going?
Open to suggestions, as its annoying me!

3 litre ZD30 diesel 2003 89000 miles

 

[Lazy-Ferret]

I am not sure if this is different depending on model/year etc, but on mine, once the ECU goes into limp mode, it does not come back out, with out a full ignition off and back on again power cycle, so based in that, I would not think it its going into limp mode... Not only that, but just the pulse of switching the MAF amp on or off, is enough to knock it into limp mode, so it does not take much at all.

I would go back to basics, and look at things like the banjo filter, and air in the fuel. I copied others on here, and put clear pipes in between the in and out pipes on the filter, and found air in the fuel after the filter... long story short, the filter housing had a split and was letting in air.

 

[Barrbeast]

I'm not sure but it does sound like it could be going into overboost safety mode (designed to prevent overboost damage to the engine and doesn't throw a fault code).

It's a bit odd it's not showing when your cruising in the higher gears at 60/70 though :nenau

Have you had a check of the ZD30 DI section on the patrol 4x4 forum?

http://www.patrol4x4.com/forum/zd30-di-engine-3-litre-71/

If you've never looked on there before try not to get too concerned when reading any of the ZD30 posts as it is an Aus forum so there is a LOT of ZD30 owners there to post on it and of course people only really post when something goes wrong...

Try the ZD30 DI bible as well :thumb2

http://www.patrol4x4.com/forum/zd30...nce-bible-newbies-start-here-zd30-info-31418/