IQ Too High ?

OK Its been a while but on this one IU am stumped.

Chap fits injectors with .216 nozzles fitted and set up by a diesel pro - tested and certified good.

Fits them and gets some black smoke, checks IQ in adaptation ch 1 and its bouncing between 6 and 12 mg/s

Any change of the stored value in VCDS does nothing to the IQ.

But its smokey, idle is erratic and cant be changed so he thinks his pump is bad - goes and gets it reconditioned by a specialist and the problem is still there.

I am tempted to hammer mod it either direction to see if we get a change in the IQ / idle.

What could cause the IQ to be this high ? Never seen this issue before.

Thanks in advance.

Bouncing IQ usually means a pump problem: either fuel leaking past a worn piston or a the quantity adjuster is failing. Changing the stored value with no change in the IQ is another indication of a worn QA.

What does "reconditioned" mean? Full rebuild of a Bosch pump rotary in the US (we don't have your vehicle here) usually runs between 700-1000 USD. Not sure what it would cost there, but I would imagine it would be similar.

The plot thickens, I just asked for readouts of gblocks 3 8 and 11 MAF Fuelling and boost.

MAF requests 850mg - Actual doesnt move from 230
Driver requested IQ is 50mg at 2224 rpm - torque linmiter IQ 41 smoke limiter 11.8
Boost requested at 2224 rpm 1994mb - actual 960mb

Something really wrong with this van.

IndigoBlueWagon said:

Bouncing IQ usually means a pump problem: either fuel leaking past a worn piston or a the quantity adjuster is failing. Changing the stored value with no change in the IQ is another indication of a worn QA.

What does "reconditioned" mean? Full rebuild of a Bosch pump rotary in the US (we don't have your vehicle here) usually runs between 700-1000 USD. Not sure what it would cost there, but I would imagine it would be similar.

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This van is in eastern europe so god know whats been done but apparently the engineer has been doing pumps for 30 years - no assurances there.

I'll get him to pull the cover and check the QA for movement on ignition and by hand