Hey guys name is Jay and my GF has an 03 A4 which just threw a P0171 CEL which I found out was a MAF. Does anyone have the directions in how to clean the MAF first before we buy a new one? I also read that it could be a hose or a crusted up MAF. If the car idles funny and bucky slightly does it need to be replaced or can I try cleaning it for her? I have also been reading it could be one of 4 vacume leaks. Does anyone have a diagram of the 1.8T on which hoses i need to check? Any help would be appreciated.


THank you

Jay

 

http://wiki.ross-tech.com/index.php/16555/P0171/000369

That's the probably causes. Like you said clean it up first, check AudiDIY or A4mods to see if you find a step by step guied on how to clean the sensor, don't buy a new one until you have tried all the possibilities on that wiki Ross-tech page.

 

there is 4 or 5 check valves i believe depending on model. if u suspect its the maf u can unplug it and see if the studder gets worse or stops if it stops its the maf and if it dosent its probably a check valve or vac line loose.

 

OK guys yesterday my friend came over who is a mechanic. We looked at the vacume lines and sprayed some carb cleaner on and around the lines to see if the car would stumble. It didnt do anything but we noticed some possible oil in and around one of the spark plugs(didnt have a tool to get the plug out). Car was driving today and at idle the CEL flashed so I had my GF bring the car home. I called Carquest and ordered a new MAF and plug just in case (MAF was $125 OEM). Anyhow I am going to try and remove the MAF today to see if I can clean it first. What size and specific tool do I need to take off the MAF?

Jay

 

OK guys yesterday my friend came over who is a mechanic. We looked at the vacume lines and sprayed some carb cleaner on and around the lines to see if the car would stumble. It didnt do anything but we noticed some possible oil in and around one of the spark plugs(didnt have a tool to get the plug out). Car was driving today and at idle the CEL flashed so I had my GF bring the car home. I called Carquest and ordered a new MAF and plug just in case (MAF was $125 OEM). Anyhow I am going to try and remove the MAF today to see if I can clean it first. What size and specific tool do I need to take off the MAF?

Jay

 

you need some special star bit to remove the security bolts, but thet can also be turned with vice grips or some other pliers.

 

So I ended up changing the MAF and took it to my friend. He stated it was misfiring so change the coilpacks and plugs. I ordered the packs and plugs the pack I got are Carlin. Does it matter what coilpacks I use? I am going to return the MAF most likely also as it was not the issue.


Jay

 

So the car is still bucking even after finding a cracked hose thinking that was the vacume leak. Turns out my mechanic thinks its this box thing which was near the hose that cracked. He started telling me what it was however I lost him when he was talking about fuel pressure. This vacume leak issue has been nothing but problems. I wish her A4 was as reliable as my WRX

So hopefully this fixes the issue and I can return the MAF however I think Im stick with the coilpacks.


Jay

 

its a good idea to do some testing to narrow down the list of potential problems before purchasing parts, and start out with cheaper fixes first

actually audi just put out a recall letter for coilpacks, your girls car may be on the list, you might want to check into that and see if you can get reimbursed

 

So needless to say the car is now fixed and runs like a champ. The issue was a very small hose a $12 part from Audi so in total it was just over $100 to get the car fixed. Alot of frustration we had before taking this car to the right place which was www.northbayimports.com I tell you what after 30-45 min of getting there they narrowed down the problem and ordered the part. I am so glad i was able to return the MAF however I have to call VW usa regarding the comment above on the coilpacks to see if they will give me my $ back. Anyhow after weeks it was a very small hose underneith the intake manifold.


Jay