Go Back  AudiWorld Forums > Technical Discussion > Performance and Tuning
Reload this Page >

Help resolving P0303 Cylinder Misfire

Performance and Tuning Discussion forum for various performance tuning techniques and questions
Sponsored by:
Sponsored by:

Help resolving P0303 Cylinder Misfire

Old 03-04-2018, 02:52 PM
AudiWorld Newcomer
Thread Starter
Join Date: Mar 2018
Location: Western NY
Posts: 1
Likes: 0
Received 0 Likes on 0 Posts
Default Help resolving P0303 Cylinder Misfire

Hi - I'm new to Audi and this forum, so please forgive my potential ignorance. I'm trying to find the cause of a P0303 CEL code. I bought my 1999 A4 2.8 Quattro (AHA engine) from a friend this past summer. Only 80K miles and well kept - all service records, routine maintenance always performed, etc. Current milage is 83K. I was driving down the highway at about 72 MPH when the vehicle started to run very roughly, the CEL came on and also flashed on and off during acceleration. I ran OBDII scanner diagnostics and determined the CEL was for a P0303 - Cylinder 3 Misfire Detected.

Rather then read through a stack of old service receipts to see if/when the plugs & wires were replaced, I just decided to replace the plugs and wires and then have a baseline for future reference. The problem didn't go away. I swapped the cylinder 2 & 3 wires and the problem remained on cylinder 3. I tested the compression and verified that the compression was the same on all 6 cylinders. I also verified that cylinder 3 was firing via in-line spark test. I haven't checked the injector yet, but that would be the end of the line for me as far as trouble shooting goes. I don't have the expertise to do much more - as I am just an aspiring backyard/weekend mechanic. I am posting this thread with the hope of gaining some insight as to other potential causes of a cylinder misfire. Any assistance would be greatly appreciated!
Fairport-A4 is offline  
Related Topics
Thread Starter
Last Post
A4 (B6 Platform) Discussion
03-10-2009 05:54 PM
VAG-COM Discussion
10-11-2007 06:19 AM
A4 (B5 Platform) Discussion
11-10-2006 07:49 PM
A4 (B5 Platform) Discussion
02-17-2006 07:30 AM
VAG-COM Discussion
10-21-2003 02:30 PM

Thread Tools
Search this Thread
Quick Reply: Help resolving P0303 Cylinder Misfire

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

© 2019 MH Sub I, LLC dba Internet Brands

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.
  • Ask a Question
    Get answers from community experts
Question Title:
Your question will be posted in: