[Engine] miss fire at idle 1.6 hdi

[smutts]

New weird one. Just happened today.

Miss fire at idle, idles on 3 cylinders, when engines warmed up.

When engines cold, first started, it idles on 4 cylinders.

Under any load, any rpm, engine runs on 4 cylinders. No loss of power.

Good compression on all cylinders.

In 1st gear, feet off pedals, idles happily  up a hill, on 4 cylinders, engage clutch, engine drops to 3 cylinders.

I'm utterly Scoobied.

Assuming a sticky injector.

Usually use Shell, but last tank was ASDA.

Any ideas?

[smutts]

Peugeot planet on it, fuel trims are way out for injector 2 at idle.
No smell of unburnt fuel at the exhaust.

So I'm going for sticky nozzle pintle not opening for the tiny fuel pulse at hot idle.
Cold idle must have just enough of a longer pulse to get the needle to lift enough.

Also there has been occasions of slight combustion rattle the last few thousand miles, which supposedly is caused by the nozzle not doing the pre-injection thing properly.
The pre-injection is also a very short pulse to get a tiny bit of fire burning before the main big pulse.
If this doesn't happen, the main pulse burns like in an old fashioned diesel, with a horrible clatter.

So short pulses not working seems to fit what the damn thing is up to at the moment.

[smutts]

Question.

Are the 110hp nozzles the same as 90hp ones?

As I have a set.

[Sol]

I expect they aren't exactly the same, or there wouldnt be 90s and 110s. But should be compatible.

No pre Injection pulse is common among Pug injector. They rattle like buggery.

[smutts]

Well, Ebay, £25 for a 56K mile injector out of a Suzuki.
injector number matches.
So am waiting for the postman.

Anyone after some 110hp injectors?

[smutts]

It's turned up at last! Excitement!
The nozzle is swollen at the tip. Disappointment.

I am guessing why the seller only had 3 injectors for sale.

One forum theory is, water in badly contaminated fuel, explodes to steam at the tip, ballooning and stretching the tip.

Eventually big chunk of tip drops into the cylinder, dances around a bit, then exits via the turbo, probably with a turbine blade or three.

With no end to the injector, high pressure diesel will pour into the cylinder & torch it.
Pre-igniting & hydro-locking engine.

Conrod exits block.

Fleabay scrappy will have three injectors for sale.

Pity, last night, I bought the other two  as well.

[smutts]

https://landroverfaq.com/viewtopic.php?t=5692&start=160

Finally found a believable reason why the injector nozzles can bulge. 

If the injector isn't clamped properly, combustion heat on the nozzles can't escape into the cooler cylinder head, also it is getting blowtorched by the hot leaking gasses.
So they overheat & weaken.

Not that the 1.6 hdi has a habit of loose injectors!

Hopefully the other two will be useable.