Login  |  Register
Nissanhelp.com - All About Nissan
Do-It-Yourself Maintenance Owners Manuals Recalls/Campaigns Service Bulletins Service Manuals Nissan OBDII Codes Glossary & Acronyms More...
Member's Ride Photos Stock Photo Gallery
Classifieds - For Sale Classifieds - Wanted To Buy Classifieds - Mechanic Wanted Classifieds - Auto Services Search Auto Parts
Register FAQ Social Groups Mark Forums Read
HELP!!! Pesky P2A03 code! Forums > > HELP!!! Pesky P2A03 code! HELP!!! Pesky P2A03 code!
Forgot Password? Join Us!

Frontier Nissan Frontier/HB/Truck Discussion Forum

Thread Tools Display Modes
Old 10-19-2018, 05:48 AM
belholm belholm is offline
Registered User
2006 Frontier Crew Cab
Join Date: May 2016
Posts: 3
Default HELP!!! Pesky P2A03 code!

Ok, so this has been driving us insane for about a month now. For reference, I've got an '06 SE 6cyl. We changed the coil-packs and plugs in early September(idle was getting a bit rough, apparently they were the originals) and about 30-40 miles afterwards the P2A03 code tripped.

We ended up replacing the indicated sensor. Again, roughly 40 miles later, the code was back. This time we dug into the freeze-frame data.

Our tame mechanic says that the P3003 indicates a misfire in cylinder #3. Going off of that, we removed the plenum and replaced the gaskets, thinking that may have been the problem(we neglected to do so when we replaced the coils). Just for good measure, we swapped the coils for #2 and #3 to see if the code followed it. No luck.
Next order of business was to try a relearn procedure that is recommended for whenever you change an O2 sensor. Again, the code was back.
Just a few days ago, we took everything apart to check if any seal or gasket had rolled and made a vacuum leak. Everything seemed clean, no cracks, rolls, splits, etc. Aaaand the code is back. Again.
Nothing specific seems to trigger it, nothing seems wrong with the rest of the engine, and everything responds just the same as it always has. Does anyone have any suggestions as to what the issue might be? Obviously, we're trying to keep it out of the shop if it can be avoided. Thanks in advance!
Reply With Quote
Old 10-19-2018, 05:50 PM
mpe235's Avatar
mpe235 mpe235 is offline
2015 Rogue
Join Date: Jun 2006
Location: New York
Posts: 5,538

Check for an exhaust leak at the flage to the catalytic converter, specifically the weld at the flange for the front pipe .
Reply With Quote
Old 10-19-2018, 10:42 PM
smj999smj's Avatar
smj999smj smj999smj is offline
Master Enthusiast
2006 Pathfinder
2003 Frontier King Cab
2003 Frontier KC SVE 4x4
Join Date: Jun 2012
Location: Prospect, VA
Posts: 1,803

Definitely check for exhaust leaks around the flange, as mpe235 recommends. There have been a number of people that have reported cracks there. Also, the flange gaskets at the catalytic converter can leak. Try starting the vehicle and after a couple of minutes, look for signs of leaking condensation at the flange gaskets, manifold gaskets and also at any potential holes in the exhaust near the incident sensor. Make sure you erase the self-learning memory or the code may re-trigger. The code is triggered when the ECM detects a lean condition based on that sensor's input. Replacing the intake gasket wasn't a bad idea. If the previously mentioned suggestions don't help, I would check the fuel pressure and make sure it's not below and, if good, possibly consider replacing the fuel injection for #3 cylinder and/or have a professional fuel injection service performed. Also, make sure the spark plugs are not due for replacement. A really dirty and restrictive air filter or a dirty or faulty mass air flow sensor can also cause this code to trigger. Also, check for splits in the rubber connectors of the air intake between the throttle body and the air filter. If they are split, Dorman has a kit to replace them (Nissan makes you buy the whole intake assembly).

Last edited by smj999smj; 10-19-2018 at 10:56 PM.
Reply With Quote
Old 10-26-2018, 05:53 AM
belholm belholm is offline
Registered User
2006 Frontier Crew Cab
Join Date: May 2016
Posts: 3

Apologies for the long time for this response, it has been a crazy week. We've looked at the seals, and can't find any leaks. They're old, yes, but not leaking. No hissing, condensation, anything. The plugs are brand new(must not have said that correctly in the original post, sorry), and we've tried swapping #2 and #3 just like the coils to the same effect. I guess next thing would be the fuel system. We'll check that and report back. Thanks again!
Reply With Quote
Old 11-06-2018, 02:38 PM
belholm belholm is offline
Registered User
2006 Frontier Crew Cab
Join Date: May 2016
Posts: 3

OK, so now we feel really, really, stupid. Turns out it was a missing bolt on the reverse side of the joint at the cat. Found it 2 days after the last reply, fixed it, and no light. I guess that's what we get for concentrating on the engine and not the exhaust... Thanks again for the help!
Reply With Quote


code, p2a03, pesky

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

All times are GMT -8. The time now is 06:04 AM.

Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2019, vBulletin Solutions Inc.
Search Engine Optimisation provided by DragonByte SEO v2.0.42 (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.