Hello everyone; I have an 2003 A4 3.0L Quattro w/94,000 miles.

I asked this before on this forum but I didn't get any response so maybe i get lucky this time.
https://www.audiforums.com/m_661670/tm.htm

It now got worst today the car started acting funny and I took it toAutozone and theypull up the codes P0421, P0431 (same as before) and P0300, P0301, P0303 & P0304.


The check enginee light came on a few days after I have Firestone do the oil change on the car but I noticed that they didn't put any windshield fluid as the light came on after I try to use it 1 time and ran out of fluid.

P0421, P0431 Some thing aboutcatalyst issues.
P0300, P0301, P0303 & P0304. Some thing about the enginee coil

Do anyone know about the codes and how to fix it without taking to the dealers? I'm out of warranty, This is not the first time I take it to the dealer about Enginee Coil are they that BAD or are they just putting bad quality parts? Is there a recall on the enginee coils for this car?

Thanks a lot in advance! [8D]

 

u prolly have a vacuum leak. no idea where to tell u to look. also check ur plugs. does ur car have individual coil packs or is it one large one. and the catalysts codes is either ur bank 1 which is the passenger side ( same as the 2.8 engine i believe) wel the problem is either the cat O2 sensor or the cat conv itself. get under ur car and hit the cat conv with ur fist and see if u hear rattling. if u don't it's most likely ur O2 sensor.

 

It have 3 Ignition Coil on each side. Not too long ag I took the car to the dealer and they replace 2 and few years back they replace some as well... Everytime is the Ignition Coil. Are they that bad or what can be causing this to fail so much?

[IMG]local://upfiles/25881/4E965DD216FF414E889998AEA9F8C3BB.jpg[/IMG]

[IMG]local://upfiles/25881/0DCBA3BC13AD4E6AB5F60567F70A5BC4.jpg[/IMG]

 

= P0300, P0301, P0303 & P0304 misfire, P0421, P0431 = catalyst or O2 sensors, I don't think its the O2 sensors but more the misfire issue so change the coil packs on cylinders 1/3/4 or the spark plugs

 

what mods and spark plugs?