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davec573
24-02-2008, 05:21 PM
Hi, recently run vag com measure blocks to check the maf and on 3 runs got a reading of 108g/s in 2nd gear on each run,my reading should be 120 g/s according to ross-tech fuel trim write up but does say if the reading is significantly lower it could be a maf problem but is 108 g/s signifficantly lower than 120 g/s ?:1zhelp:

Thanks in advance

Davec

RSTuning
27-02-2008, 12:02 AM
Does it say to run in second on the site?

Do a full throttle run in third and post the logs so we can see.

Paul

Eshrules
27-02-2008, 09:33 AM
As above, IIRC, Rosstech states to run in 4th, the general idea being to run the car in high a gear as possible.

3rd or 4th gear are ideal.

get it on the motorway where it is safe to do such speeds, with a friend on the passenger seat, monitoring the logs etc and report your findings back here, or even better, a screendump of the actual graph would be useful.

:Blush:

davec573
28-02-2008, 09:46 PM
Does it say to run in second on the site?

Do a full throttle run in third and post the logs so we can see.

Paul


Yes,i followed this taken from ross-tech web site

Here's a good sanity check for the status of your MAF. Do a full-throttle run all the way to redline in a single gear (second works fine). Group 002 usually shows air mass in g/s (in many modern ECU's, consult your Factory Repair Manual for the specific group for your particular vehicle). Your peak airflow should be roughly 0.80 times your horsepower. So, if you have a stock 150 hp 1.8T, expect around 120 g/s. If you see significantly less than that, you MAF may be on the way out.

I will try 3rd&4th as suggested but i ran it today on my own and man its fast red lining in 3rd&4th , i had my son read the lap top in the rear of the car last time but i dont fancy them speeds with him in the car so i will have to get another bod.

Crasher
28-02-2008, 09:49 PM
Isn’t it a lot easier to just fit a new genuine MAF?

RSTuning
29-02-2008, 01:22 AM
Yes,i followed this taken from ross-tech web site

Here's a good sanity check for the status of your MAF. Do a full-throttle run all the way to redline in a single gear (second works fine). Group 002 usually shows air mass in g/s (in many modern ECU's, consult your Factory Repair Manual for the specific group for your particular vehicle). Your peak airflow should be roughly 0.80 times your horsepower. So, if you have a stock 150 hp 1.8T, expect around 120 g/s. If you see significantly less than that, you MAF may be on the way out.

I will try 3rd&4th as suggested but i ran it today on my own and man its fast red lining in 3rd&4th , i had my son read the lap top in the rear of the car last time but i dont fancy them speeds with him in the car so i will have to get another bod.


Ok, unokug the MAF, does it go better?

davec573
29-02-2008, 08:08 PM
Isn’t it a lot easier to just fit a new genuine MAF?

If i knew it was the maf yes..but if its not, its a waste of £62 don't you think??


rstuning- dunno i will try it,cheers

Davec

davec573
29-02-2008, 09:23 PM
Ok, unokug the MAF, does it go better?

Unplugged it and its very erratic/pulsing up & down from normal idle 1000rpm ish dropping to allmost cutting out.
engine management light up again today,seems to be every 100mls,i'll post up my scan.

Davec

davec573
29-02-2008, 09:39 PM
Unplugged it and its very erratic/pulsing up & down from normal idle 1000rpm ish dropping to allmost cutting out.
engine management light up again today,seems to be every 100mls,i'll post up my scan.

Davec

heres the scan...

VAG-COM Version: Release 409.1-US
Control Module Part Number: 8E0 906 018 B
Component and/or Version: 1.8L R4/5VT 0003
Software Coding: 11701
Work Shop Code: WSC 63351
Additional Info: WAUZZZ8EZ1A026150 AUZ6Z0A0012083
2 Faults Found:
17544 - Fuel Trim: Bank 1 (Add): System too Lean
P1136 - 35-00 - -
16486 - Shareware Version. To Decode all DTCs
P0102 - 35-10 - Please Register/Activate - Intermittent

and a screen dump from measuring blocks at idle...

Crasher
01-03-2008, 03:47 PM
A Denim Blue Audi A4 quattro 1.8 with an AVJ engine built on 31/01/2001 and registered in the UK on 01/03/2001)

Normally I would say "no power, no codes new MAF" but as your car has fault code “16486 P0102 035 Air mass metere-G70 Signal too low” I would certainly say replace it if that was read before you disconnected it.

RSTuning
02-03-2008, 12:39 PM
Just realised these will run crap with no MAF.

As crasher says, try a maf as it's always handy to have a spare anyway!

Paul