Mystery puff

Mystery puff

Postby MADMETHBANSHEE on Fri Jun 03, 2022 8:21 pm

. ive been a member for a long time as ive had my MQ since 2015.
The tech advice is great and i was wanting to ask a few questions around an issue i have.

My mq puffs white smoke, only once and only at the end of my street when cold for about a month. once its warm it doesnt happen again. until last week when i drove home on a particuarly cold arvo. i tthought it was only doing it when i turned. i went home and noticed the overflow bottle was low, now i initially thought this was relevant but the weekend prior i removed my airbox and moved the overflow so it could have drained out.
i use blue penrite which i changed more than a year ago and when i drained it to pressure check the egr cooler it was more green than blue.

anyhow i thought the white smoke was due to not draining the catch can in time. but then moved onto egr cooler which passed a 20psi test in a bucket of water.
now ive removed the intercooler and piping and cleaned as there was a fair bit of oil in them.

after some forum searching i decided to look on top of the motor. around injector 2 there is a black brittle glass like substance, the heavy fitter at work tells me it could be carbon and diesel due to a bad injector seal. id like to know if these just fail or is there a chance its been installed wrong. last time the injectors were out were for valve adjustment 20k ago.
ive had mitsi replace a seal before when it was newish.
my local dealer cannot look till next wed.
i should add the ute runs sweet, never ever has gotten hot or more than half way in its life. i have a scangauge and watch it religiously. it starts fine and appart from the white puff id have never had a reason to check it. also last time i dropped the oil (one month ago) it had made some oil about 5mm over hi mark. i previously thought it was due to dpf burns (which i have never ever seen it do)
it as 159k on it now. should i prepare for bad news? also mitsi are the only ones to have ever pulled the top off. i do my own oils after warranty expired.

bit if a long winded explaination but the wait is driving me crazy.
Posts: 67
Joined: Tue Dec 29, 2015 8:15 pm
Location: Western Australia


Re: Mystery puff

Postby DibbyDibbyDJ on Sat Jun 04, 2022 8:52 am

The glass like substance is due to the leaky injector. This is very likely caused by poor workmanship, as you say, when doing the valve clearances.

Injectors are $1000 each, and the cover is about $800, so its important for you to ensure this is the dealers [censored] up. As long as the dealer is the only person to remove the injectors, then that is good. But a dealer will only guarantee their work for 12months or 20000kms. but this problem will only normally show up after that period. Be prepared to get MMAL involved.

If your vehicle has been serviced to the specifications this will help. if it has missed a valve adjustment, then be prepared for a fight, as whilst poor workmanship is the dealers responsibility, getting the work done is the owners

The white smoke may be caused by a crack in the cylinder head where the injector has been badly fitted.

This will be expensive for someone. Hopefully not you.

I have replaced numerous cylinder heads and injectors on 4N15 engines caused by incorrect fitting, luckily all have been serviced elsewhere, some by dealers, where MMAL have assisted in charging the dealer, even though they denied it was their fault, But mainly, sadly some were borne by the owner as the vehicle had had the valves done outside the dealer network, and the independents were not interested in contributing to a repair.

The procedure for refitting injectors is very precise, and i bet no independents have the manuals or have bothered to find out the procedure.

Dealers have no excuse, they have all the info, so this should not happen.
Silver 2020 MR (4N15) Sportsbar, Towbar, EDS
Posts: 408
Joined: Mon Oct 07, 2019 8:16 pm

Re: Mystery puff

Postby MADMETHBANSHEE on Sat Jun 04, 2022 9:04 am

Ok thanks for the info. It's definitely only ever had valve adjustments done by local Mitsubishi dealers.
I'll see what they have to say then next Wednesday
Posts: 67
Joined: Tue Dec 29, 2015 8:15 pm
Location: Western Australia

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