ZD30 engine miss
Nissan Navara ST-R, D22 crew cab, 2004 build, ZD30 diesel turbo, no aftercololer (prior to common rail). Engine has done 115,000 k's
Engine misses slightly in 3rd gear and noticeably in 4th gear when engine is warm (never cold or when lugging) accelerating between 2-3000 rpm, and has been well serviced. Have done fuel filters (often) and blown back thru' fuel hoses to prove tank strainer is clear. I'm told I can't blow back thru' fuel pump nor gain access to fuel pump strainer without removing injector pump (timing cover and timing chain, about $750 to look).
"Experts" have come up with all sorts of prognosis (?), the most likely (and expensive) is to remove the injector pump and clean small strainer in injector pump (which can't be got at externally so I'm told).
This doesn't make sense to me because the symptom should be evident in all gears if it was lack (starving) of fuel. There is no evidence of any excessive exhaust smoke, clean as a whistle.
I suspect that I have a computer/chip/program problem but when discussing a chip replacement Nissan, they said it wouldn't prove anything saying that 'after-market' chips were available, missing the point completely. I asked if an analyzer would show up the problem, "it might, but in diagnosing the problem it could take 5 minutes or five hours."
I am a vet and don't have an open cheque book. A mechanic had a hand-held analyzer on it and it didn't show anything out of the ordinary.
Any ideas, I am support crew for a motor bike rider in the Australasian Safari late July and would like this glitch sorted before hand.