[Engine] lexia & PP2000 idle flow corrections, 1.6 hdi

[smutts]

Elsewhere I'm trying to sort an idle miss fire.

Leak off tests were unexpectedly even, no sign of leaky ball valve nonsense.

Easy to work out which injector is not firing, 
No. 3 from gearbox, when unplugged makes no difference to lumpy idle.

Using Peugeot Planet/ Lexia.........
Engine fault code  confirms it's cylinder no.3 that I had unplugged.
which is right for the French arse about face way of cylinder numbering.

But, when looking at the figures for idle corrections, cylinder number 2 is being signalled to get way more fuel, 
in order to try and smooth out the idle. 

Surely it's cylinder number three that would be getting the orders for more fuel?

Or am I missing something?

[Sol]

Probably means no2 is also buggered.

You are never meant to run these injectors unplugged btw. Citroen issued a red notice to all mechanics not to do so in the TSB documents. It kills the injector by forcing pressure into it the wrong way when it is not able to push back.

[smutts]

Probably means no2 is also buggered.

You are never meant to run these injectors unplugged btw. Citroen issued a red notice to all mechanics not to do so in the TSB documents. It kills the injector by forcing pressure into it the wrong way when it is not able to push back.

I've just read that too!
My guess would be that by doing this, you risk killing the driver circuit in the engine management black box. 
Fortunately I look to have got away with that one.

Some diagnostic software's allow you to disable injectors in turn to allow you to track down miss fires.

Does Lexia/ PP2000 have this ability?

[Sol]

Mmm not seen that function in Diagbox.

[smutts]

Any good ideas on how to find a miss-firing injector?
If unplugging is a very bad idea?

I suppose you could use a spare injector coil to swap for the injector you want to turn off.

Pity Lexia can't do it.

Going stir crazy waiting for injector nozzles to be posted 20 miles from Swilly.

[Sol]

The issue is, when you unplug an injector, the engine compression buggers it. Using a surrogate has no effect. The ECU doesn't give a toss if you unplug the injectors. They get mechanically damaged by doing that.

When there is no fuel pressure behind the lift needle, the engine compression shoves carbon up the end, killing the injector. AFAIK.

Maybe do a leak back test. That how injectors are normally tested if you didn't have a POP rig.

[smutts]

If the compression vs unfired injector were damaging, then engine braking downhill would kill them in short order. Possibly, maybe. who knows.

But if it is.......................
"Thou shall not unplug the running injector lest the horrors of great Bosch expense will be laid upon your worthless Berlingo!"
.............................Then I shall take heed.

Might be worth a thread to try and pool knowledge of the principles of common rail systems.

[smutts]

Just for some reading with a coffee.
Good explanation of I think of what is going on with injectors.

https://autoditex.com/page/common-rail-i...-25-1.html

http://www.dieselcatalog.online/en/bosch...10239.html


  bosch common rail.pdf (Size: 448.06 KB / Downloads: 2)

As I was thinking about using a pop tester to set the nozzle lift pressures. I would need the injector set to "open". 

My first (naive!) thoughts were to put 12v to the coil, but the ohms of the control coil is very low, about 0.5 ohm.
If you connected a 12v battery to it, that would be about 300 watts.
that will melt them. the pulses from the engine management are very short, so they don't overheat in normal use., 

Second thought is to remove the 1mm ball bearing for testing, but then there would be a dead leak up the return line.

Third thought, bugger it, swap for a new nozzle & hope for the best.

[Sol]

Third thing would be my choice. Why make it harder than it needs to be.

I can't think why it is an issue either, but the Gods of Citroen say "thou shalt not disconnect the injector while running...lest we smite thee!"

It's Turtles all the way down!

[smutts]

If people are swapping nozzles, this might help.
Yup the 60NM torque I was using, given on some site wasn't right.


  kupdf.net_222024224-bosch-cri-repair-instructions-maktest-pdf-1pdf.pdf (Size: 3.03 MB / Downloads: 3)