Quaintbucket Posted July 29, 2014 Share Posted July 29, 2014 Ok, I am having a lot of trouble with my pathfinder passing smog and I am literally stumped. I am taking it to a mechanic to do a professional diagnose because I don't know where to go from here. My NOX is high and my HC and CO is fine. I have done the following in this order: 1) inspect and clean EGR. It wasn't gunked up or anything. 2) sea foam intake manifold Took it to smog again and the test results got worse. Huh??? 3) inspect and clean MAF sensor 4) found vacuum leak on air intake duct boot to intake manifold 5) replaced spark plugs 6) replaced spark plug wire 7) replaced dist. Cap 8) replaced dist rotor 9) replaced fuel filter 10) replaced air filter 11) check for exhaust leak (none...) 12) relocated knock sensor (threw a code) No codes anymore. Took it to smog test after driving 150km. Failed aircare but not as... Horrible? Still no codes. I'm at loss for words. Any ideas? The vacuum leak was brutal (two major cracks) that threw p0171. I'm starting to think I should just throw in acetone in the fuel tank just to cheat. Any ideas?? Link to comment Share on other sites More sharing options...
Quaintbucket Posted July 29, 2014 Author Share Posted July 29, 2014 Also, for more information if it helps some people figure this out... When I am driving, if I try to slam the gas pedal to the floor, it will rev about 4k rpm but the speed will not go up unless I ease off on the pedal then it will surge forward. Link to comment Share on other sites More sharing options...
Slartibartfast Posted July 29, 2014 Share Posted July 29, 2014 Sounds like it's still running lean. Maybe there are more vacuum leaks? Check the oxygen sensors? Also sounds like your transmission is slipping. That's not good. Link to comment Share on other sites More sharing options...
Quaintbucket Posted July 29, 2014 Author Share Posted July 29, 2014 Wouldn't it throw a P0171 code? My reading was double the maximum allowed. Did not see any obvious vacuum leaks. Haven't checked 02 sensors. On way to mechanic for a diagnosis. Link to comment Share on other sites More sharing options...
Quaintbucket Posted July 29, 2014 Author Share Posted July 29, 2014 02 sensor was not ready. Evap was not ready. I am taking it for a good drive and then will bring it back. The mechanic noticed the MAF sensor. Brought it to me caked in gunk. I was surprised. He cleaned it free if charge. Guess I did not clean it as well. I was scared to touch it. After driving it for a bit... It feels a lot better. I did the iron foot test and it did not do that surge. More to drive. Coffee break and heading back. Cheers. Link to comment Share on other sites More sharing options...
Quaintbucket Posted July 29, 2014 Author Share Posted July 29, 2014 Drove it. Get all system ready. Pulled 2 codes. p0440 and po446. Small evap leak most likely. This suggest the cats are fine. Shop is busy right now but will do a smoke test early afternoon. Right now I'm going to the park with my daughter to have lunch and have fun. My question is: can an evap leak cause nox? I know the MAF SENSOR would most likely be the biggest cause because it was so caked on with gunk. Would make sense because accerlation did feel like the car was choking. Link to comment Share on other sites More sharing options...
Quaintbucket Posted July 30, 2014 Author Share Posted July 30, 2014 PASSED. it was the mass air flow sensor caked with gunk. Test results was amazing. It was if I just bought it after 2003. 1 Link to comment Share on other sites More sharing options...
Terranovation Posted July 30, 2014 Share Posted July 30, 2014 Phew at least it's fixed now! So glad we don't have these emission tests here in Oz Link to comment Share on other sites More sharing options...
Quaintbucket Posted July 30, 2014 Author Share Posted July 30, 2014 Yeah now I have p0440 p0450 and p0446. All EVAP. I think it is just one part doing this. Will just go to a junkyard and do a part swap. Not critical to my emission, fuel mileage, or performance, Link to comment Share on other sites More sharing options...
Alkorahil Posted August 4, 2014 Share Posted August 4, 2014 Yeah now I have p0440 p0450 and p0446. All EVAP. I think it is just one part doing this. Will just go to a junkyard and do a part swap. Not critical to my emission, fuel mileage, or performance, These are the classic early R50 3.3L evap cannister issues. The charcoal in the evap cannisters after about 10 years decayed and destroyed the cannister valves. I would recommend replacing both the cannister and the valve with the newer versions Nissan now provides. A vehicle in the salvage yard will most likely already have the same problem or create the same problem. Link to comment Share on other sites More sharing options...
Quaintbucket Posted August 5, 2014 Author Share Posted August 5, 2014 Damn, that's definitely not something I want to hear. do you have the part numbers for those new ones? What caused the evap to fail like that other than age? Just out of curiousity because this is the first I've heard about it. Link to comment Share on other sites More sharing options...
Precise1 Posted August 5, 2014 Share Posted August 5, 2014 PASSED. it was the mass air flow sensor caked with gunk. Test results was amazing. It was if I just bought it after 2003. Interesting to know that a dirty MAF has such a profound effect, and it sounds like the mechanic is a good one. Might want to keep him in mind... B Link to comment Share on other sites More sharing options...
Quaintbucket Posted August 6, 2014 Author Share Posted August 6, 2014 I have used him in the past when I had a Kia Sportage. He is closer than my other mechanic who helped me with my Ford Ranger. Both are great mechanics. He already found the problem with my evap system. The vent solenoid is not working properly so I'm going to try to clean it and see if yhT clears the code after a drive cycle or two. If not, I will replace it. $53 compared to $173. Link to comment Share on other sites More sharing options...
Alkorahil Posted August 6, 2014 Share Posted August 6, 2014 Damn, that's definitely not something I want to hear. do you have the part numbers for those new ones? What caused the evap to fail like that other than age? Just out of curiousity because this is the first I've heard about it. There are a few variations for those parts. If PM me your VIN and I can get you the prices for your vehicle. Link to comment Share on other sites More sharing options...
Alkorahil Posted August 6, 2014 Share Posted August 6, 2014 He already found the problem with my evap system. The vent solenoid is not working properly so I'm going to try to clean it and see if yhT clears the code after a drive cycle or two. If not, I will replace it. $53 compared to $173. More than likely cleaning it will not do anything as the part is damaged from the small pieces of charcoal from the cannister blowing though it. When the charocal in the cannister starts to break down it blows through the solenoid and damages the inside of the solenoid. If this problem goes on for a long time, there is no charcoal left in the cannister, thus making it not function. We have cracked a few open before that felt very light and they were empty. Replacing the cannister by itself doesnt fix the valve issue and replacing the valve will either cause it to get damaged again as the cannister continues to break down. So what usually happens is: Bad cannister + damaged solenoid -> Check Engine Light. Bad Cannister + Good Solenoid -> Check Engine Light Damaged solenoid + Good Cannister -> Check Engine lLght I have even seen a few that had to have the evap lines blown out with compressed air because the charcoal had clogged up the evap line. Link to comment Share on other sites More sharing options...
Manik Posted August 6, 2014 Share Posted August 6, 2014 Be glad we're all driving pathfinders. I have a 01 4Runner that the canister is leaking on and that thing at the JY is over $400, just short of a new one between $450-500. Rediculous the cost of these things. Link to comment Share on other sites More sharing options...
Quaintbucket Posted August 6, 2014 Author Share Posted August 6, 2014 More than likely cleaning it will not do anything as the part is damaged from the small pieces of charcoal from the cannister blowing though it. When the charocal in the cannister starts to break down it blows through the solenoid and damages the inside of the solenoid. If this problem goes on for a long time, there is no charcoal left in the cannister, thus making it not function. We have cracked a few open before that felt very light and they were empty. Replacing the cannister by itself doesnt fix the valve issue and replacing the valve will either cause it to get damaged again as the cannister continues to break down. So what usually happens is: Bad cannister + damaged solenoid -> Check Engine Light. Bad Cannister + Good Solenoid -> Check Engine Light Damaged solenoid + Good Cannister -> Check Engine lLght I have even seen a few that had to have the evap lines blown out with compressed air because the charcoal had clogged up the evap line. Oh wow, that's no good and depressing at the same time. PM sent w my vin number. Why would they not put a filter media between the solenoid and the charcoal canister? Doesn't seem like it would take very much unless it would restrict the flow more than necessary? Link to comment Share on other sites More sharing options...
Alkorahil Posted August 6, 2014 Share Posted August 6, 2014 Oh wow, that's no good and depressing at the same time. PM sent w my vin number. Why would they not put a filter media between the solenoid and the charcoal canister? Doesn't seem like it would take very much unless it would restrict the flow more than necessary? I hear that, it is but just one of those 3.3L R50 things. Yes it would, I base this on that I know certain model subarus had a filter on the canister that you remove because it clogs up! They even had a TSB about removing and deleting it. Link to comment Share on other sites More sharing options...
Alkorahil Posted August 6, 2014 Share Posted August 6, 2014 02 sensor was not ready. Evap was not ready. I am taking it for a good drive and then will bring it back. The mechanic noticed the MAF sensor. Brought it to me caked in gunk. I was surprised. He cleaned it free if charge. Guess I did not clean it as well. I was scared to touch it. After driving it for a bit... It feels a lot better. I did the iron foot test and it did not do that surge. More to drive. Coffee break and heading back. Cheers. I could defiantely see the gunked MAF would cause it to run lean for sure as it is not sending proper readings to the ECU about how much air is coming into the engine. You will probably notice an improvement in throttle response, power and some MPG. The O2 sensor not ready I find interesting though. Did it pass emissions barely or at the higher end of acceptable? OR did he test the emissions with the engine 'cold' or after resetting the ECU recently? Link to comment Share on other sites More sharing options...
Quaintbucket Posted August 6, 2014 Author Share Posted August 6, 2014 Oh, I should have clarified. What happened was I did some work on my pathfinder the weekend, I cleared to code to see if the P0325 would come back again (it did not). I just haven't completed the drive cycle before bringing it to the mechanic a couple days later. He said they weren't ready. Drove for 100km, following the FSM instructions to get all the system ready, brought it back with the new codes for the evap system. He quoted me $173 for the solenoid, I declined and brought it to AirCare and passed the same day. By the way, the P0450 disappeared last week. Just P0440 and P0446. Link to comment Share on other sites More sharing options...
Quaintbucket Posted August 6, 2014 Author Share Posted August 6, 2014 I could defiantely see the gunked MAF would cause it to run lean for sure as it is not sending proper readings to the ECU about how much air is coming into the engine. You will probably notice an improvement in throttle response, power and some MPG. The O2 sensor not ready I find interesting though. Did it pass emissions barely or at the higher end of acceptable? OR did he test the emissions with the engine 'cold' or after resetting the ECU recently? Oh, I goofed... let me just get the results. Pay attention to the dates. It was literally less than 24 hours in between. The only thing that was done was cleaning the MAF sensor. The throttle response, power, and MPG has changed dramatically despite being a hog with the AC. Night and day. Link to comment Share on other sites More sharing options...
Quaintbucket Posted August 8, 2014 Author Share Posted August 8, 2014 Ok, that was weird. It looks like my beck engine light went away. P0446 is no longer pending. Looks like it was definitely dirty because I haven't done anything I it yet. Will clean it this weekend and see if I can add a filter to protect it from charcoal. Any advices? Link to comment Share on other sites More sharing options...
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