Spent 3 days getting angrier and angrier at an emissions fault on a truck because I can't figure it out, what with:
- Having no documentation.
- Having my boss treating me like an idiot
(Because I'm trying to work through it methodically and figure this shit out, black-box stylee; he's just decided it's obviously exactly the same as an engine from a totally different manufacturer, and telling me to do things that I can't do because the sensors that are there on the other engine ain't here on this one!)
(Also, barging in once I've worked my way to "hm, maybe the EGR cooler is blocked? Gonna hafta take that off and clean it" to shout at me "THAT'S WHAT I TOLD YOU TO DO 3 HOURS AGO!"; as if he wasn't going to scream and shout at me if I started with the EGR cooler, because it's an utter pig of a job to remove. 🙃) - No-one in work's contact network having much experience with Isuzu trucks, nor wanting anything to do with them.
Anyway, I finally gave in and spent a couple of hours of my own goddamn time at home digging up copies of manuals because this shit is itching away in the back of my brain.
(Fuck scribd.)
And bugger me with a cactus, no wonder I can't find the pressure sensor it must obviously have:
the ECM will open the EGR valve while monitoring the mass air flow (MAF) signal. An expected MAF difference should be detected between the closed and open positions.
Who in the absolute fuck would have seen that coming?! "Ah, yes! The ECM gets its feedback about the EGR flow from detecting the inlet manifold leak the EGR valve creates."