Hi everyone,

I have a MK1 Octavia VRS 2003. My engine management light has recently illuminated. I borrowed a gizmo from my brother which has given me the code P0171. After researching this site i was led to the breather hose which i found to be split. this was repaired and the warning light reset.

the engine light has now returned with the same code P0171. On cold wet mornings the car coughs and splutters until warm and once warm it accelerates as though its taking 2 steps forward half a pace back. I have checked for other split hoses and found none. i have read that it might be due to the maf sensor. People have mentioned that i can remove / disconnect the maf sensor to return the car to factory settings and this will tell me whether or not it is the sensor at fault. If i do try this do i simply unscrew the sensor and remove it?? also if i replace or clean the sensor do i have reset anything afterwards.

I am a novice at mechanics. i have replaced ignition coils and that was my limit. i would appreciate any advice in laymans terms please and also if you think this is beyond my expertise then please say so, i will only break something else whilst trying this if it isn't easy.

Thank you in advance for your advice.

Chris

Just unplug the multiplug from the MAF sensor then go for a short run in the car, if it feels like it's driving better with the MAF sensor unplugged then the MAF is knackered and needs to be replaced. P0171 (16555) is a MAF fault code so that seems likely.

I think there is a MAF adaption you can do using the VCDS/VagCom software (check on the forum here to see if anyone local to you has it) but I don't think it's essential, it's more to do with if you're replacing the standard MAF with a bigger diameter one (e.g. S3 or Modshack ones), your ECU should be used to using the standard 2.5" MAF.

Yep sounds like a dead MAF. As above just unplug the connector on the MAF, & go for a run. Don't buy an aftermarket MAF as they usually don't work correctly, get a genuine VAG MAF. You don't need to reset anything for the new MAF as the ECU will self adapt over a few driving cylcles, but you'll probably have to get the code cleared to put the engine management light out.

Thanks to you both, new maf fitted today, cost £82 from VW Daybrook nottingham. Car running like a dream.

Appreciated your quick replies

Hi

for some time ago it appearing an error code P0171 on my RS Octavia Mk1 2002.

I just use some cheap bluetooth obd with my phone (torque) , so the error it was just in the ecu not on MIL .After a while the error appeared more freqvently and become a permanent error code written in red

Then appeared on dashboard too (mil).

So i had to find a solution to resolve the problem .

As i read in many forums , likely is the MAF or Broken hose, or O2 , i started with hoses because last year i had two hoses broken.

I started to check by listening at the engine and while i was concentrating on a special leak sound , i started to move the pipes all around, was hard with those on bottom part of pcv.

Then i heard the leak sound changing in frequency gotcha ,,....i touched the whole hose by finger and found two cracks.

I changed with home made way better quality hose and i cleared the error code from the ecu.

Today morning i tested and drived 5-10 km and the error did not came back and the car was pulling way better , the idle was smoother than before i think ,so i'm happy , and hope that this error not comming back soon

The cost was 0 , just 10min diagnosing and finding the problem , and 30 min to change .

I just shared my case because more solved problems lead to help people quicker and more precise.

Edited 13 May, 201313 yr by gjenck