5th Injector Leak if disconnected and EGR valve

[emtaboy]

Hello.  Like many others, having white smoke issues on 2AD-FHV D-CAT engine, and problem narrowed down to 5th injector.  Mechanic wants to just delete it from ECU to stop all regenerations.  I realize implication for the DPF if this is done and need to empty it.

My question is if this 5th injector, when mapped out of ECU but still connected to fuel pump, will eventually leak?  That is, injector was not designed to stay closed permanently, and when still receiving fuel under pressure from pump, can't it eventually leak and, again, result in white smoke?

 

Mechanic also wants to disable EGR from ecu when doing the reprogram.  If this is done, engine is still emitting exhaust up through tube to EGR valve, which of course will be closed after delete from ECU.  But the entire tube going from bottom of engine to EGR valve will eventually fill with carbon buildup.  Wouldn't it be better to place metal plate at engine block to stop all exhaust gas from entering EGR tube instead of just allowing it to become stuffed with carbon buildup?

 

Thoughts appreciated.  Thanks you.

[yossarian247]

I can't see any particular reason why an unused injector would begin to leak. Injectors can sometimes begin to dribble slightly after very high mileages but that's due to wear from use, and an injector that's not used at all shouldn't be subject to any further internal wear. If anything it might eventually stick closed and refuse to ever open again.

Surely with the EGR pipe if nothings going through it due to the EGR valve being permanently closed then it won't fill with carbon, and even if it did, if nothings going through the pipe anymore why would it matter that it's full?! It would just be blanked off with carbon instead of being blanked off with a metal plate. I think people sometimes blanked off EGR valves with a plate to fool the engine ECU into thinking the EGR was still working, but if its being mapped out in the ECU it shouldn't matter.

Bear in mind that all of the above would be a potential MOT test fail in the UK, but may not be where you live.

 

[emtaboy]

Thanks for the reply.  My thinking was just to be extra cautious/complete by physically stopping fuel from reaching the 5th injector and stopping the EGR valve/tube from being damaged by lots of carbon buildup.  This is important if the EGR and 5th injector may be placed back in service in future.  Mechanic thinks not necessary, but this may be just to avoid extra work of plugging 5th injector at the fuel pump and removing/replacing EGR valve/pipe to insert a physical plate.

Realize the implications for passing annual tests but it seems that if one really wants to eliminate future headaches, this is only real solution.  These systems were never designed for longevity or maintenance cost efficiency.  Of course they can work, but you will spends much too much to clean/maintain to keep them working.  Something which those of us who have these cars know quite well.