maf reading at idle

[reverse.rake]

Just wondering if anybody knows the spec for maf reading at idle? I just put a new Hitachi sensor on which has definitely fixed my boost hesitation, but according to vagcom idle reading is about 5.5 - 6.5 g/s which seems high to me considering I've read it should be around 4.5? Also seem to be misfiring more than usual at idle since new sensor..?

[julex]

reading at idle depends on many many factors, most important one being how much is throttle open and condition of vacuum system (if vacuum has leaks, then the maf readouts will be less). Ambient temp, AC on, electrical load, PS resistance, all of these will alter load and thus maf readout.

Rather than worry about that, access block 032 and verify that you don't see wonky fueling corrections (up to +-5% is ok).

[reverse.rake]

reading at idle depends on many many factors, most important one being how much is throttle open and condition of vacuum system (if vacuum has leaks, then the maf readouts will be less). Ambient temp, AC on, electrical load, PS resistance, all of these will alter load and thus maf readout.

Rather than worry about that, access block 032 and verify that you don't see wonky fueling corrections (up to +-5% is ok).

hi thanks for the reply, i really should have supplied more information in original post heh. ECU is chipped with a APR stage 2 test pipe file (91 oct) its your typical stage2+ car, vacuum at idle is perfect - 20 h/g according to podi mechanical, idle fuel trims are consistently around -2% give or take however LTFT are around -7%/-9% i guess thats pretty rich. MAF reading at idle is now showing 6.5 - 7.5 g/s i logged 003 with a 3rd gear pull to about 6200 rpm and got 260 g/s. Timing belt less than 2000km everything replaced with continental kit and block 92,93,94 are showing -2,0,-2 cf at idle, everything electrical is turned off and AC system is deleted. Had a shop perform a smoke test (they said thats how they test for boost leaks? said only 3 psi used though..) said its leak free, podi gauge is showing 16psi WOT tapers to about 13 psi redline. No misfires WOT only at idle, counting about 12 misfires max on both banks before counter resets. no fault codes.

[julex]

It is what it is then. The fuel trims are taking care of fueling inaccuracies and if there is no leaks... However. Negative fuel trims at part/med load might indicate boost leak past trubo, but before manifold. When shops smoke test, they usually only do it at throttle, that's already past majority of large leaks 2.7t motor could develop. I would look into putting your own boost leak tester together (coupld of HD/Lowes parts and a compressor) to see if/where are you leaking. Usual spots and hoses at ICs etc.

[bruddha]

Bump! Need help
Over the weekend I swapped to a 450 fuel pump and 1000cc injectors. I'm having my tuner fo an e85 revision for me. Hes requesting that my MAF at idle reads 5 - 5.5g/s. No matter what I do, I am continually near 4.5 - 4.8 g/s. I have tried to tighten everything and even swapped to a new Hitachi MAF sensor and still no difference. What am I missing? Is it normal to be between 5 and 5.5 at idle?