Jacobg Posted June 30, 2010 Share Posted June 30, 2010 So i bought a pathfinder. Not smogged. Owner said check engine light came on and off. Went to smog it and light came on during the test. mechanic figured it needed a 02 sensor so he replaced that. It ran rough so he cleaned the maf and ecu connections. So it runs good now and no cel. He smogged and it passed but i had to test at a test only station and there it failed at 25 mph. I was trying to get an idea of anything else it could be. Mechanic checked the egr and it passed. Dont believe there are any holes in the exhaust and the car runs how it should. What can it be? Link to comment Share on other sites More sharing options...
RJSquirrel Posted June 30, 2010 Share Posted June 30, 2010 (edited) Check your ignition timing. You probably need to give the engine a tuneup: new plugs/cap/rotor/wires/timing. Sea-foam your engine to clean out the carbon. High NOX is usually caused by high combustion temperatures. You might also have a vaccuum leak, a clogged fuel filter, clogged fuel injectors, dying fuel pump. The engine might be overheating. Bad water pump/Thermostat/low coolant? Anything that causes the engine to run too lean/ too hot will have an adverse effect on NOX. Good luck. Let us know how it goes. Edited June 30, 2010 by RJSquirrel Link to comment Share on other sites More sharing options...
Jacobg Posted June 30, 2010 Author Share Posted June 30, 2010 it seems to run fine. and has been kept up on all maintenance. So possibly the carbon cleaning might help. Link to comment Share on other sites More sharing options...
silverton Posted June 30, 2010 Share Posted June 30, 2010 It might also need the catalytic converter replaced. Link to comment Share on other sites More sharing options...
Jacobg Posted June 30, 2010 Author Share Posted June 30, 2010 with the cat though. I would have thought some code would have come up and the cel would still be on . Link to comment Share on other sites More sharing options...
KovemaN Posted June 30, 2010 Share Posted June 30, 2010 There are no sensors after the cat so the computer won't know if it's bad or not. It shouldn't cost you too much to get a hi-flow cat installed. Make sure to recycle the old one. It could net you $75-100 at a recycler. Link to comment Share on other sites More sharing options...
Jacobg Posted June 30, 2010 Author Share Posted June 30, 2010 wouldnt i feel it running different if the cat was bad? Link to comment Share on other sites More sharing options...
KovemaN Posted June 30, 2010 Share Posted June 30, 2010 Different from what? Didn't you just get this truck? Link to comment Share on other sites More sharing options...
Jacobg Posted June 30, 2010 Author Share Posted June 30, 2010 Well not running normal. It feels like its running normal. This is my second pathfinder. Link to comment Share on other sites More sharing options...
Jacobg Posted June 30, 2010 Author Share Posted June 30, 2010 Also something off topic. does anyone on here have a picture of a pathfinder with SE wheels painted black? Link to comment Share on other sites More sharing options...
Tungsten Posted June 30, 2010 Share Posted June 30, 2010 why not look in members rides or off-topic sections Link to comment Share on other sites More sharing options...
Jacobg Posted July 1, 2010 Author Share Posted July 1, 2010 I found a car with them. Link to comment Share on other sites More sharing options...
R3DN1CK Posted July 1, 2010 Share Posted July 1, 2010 Do you have the readings from the smog report? Link to comment Share on other sites More sharing options...
silverton Posted July 1, 2010 Share Posted July 1, 2010 It wouldn't necessarily run bad. It would just be slower than usual, but not too much. Link to comment Share on other sites More sharing options...
Jacobg Posted July 1, 2010 Author Share Posted July 1, 2010 Do you have the readings from the smog report? yes i do.Ill tell u the numbers i got. 1st smog done by previous owner. Nox 15mph--Max 350---330 pass Nox 25mph--550---725 fail Smog by my mechanic before new 02 sensor 15 mph-- 1200 gross pollute 25mph---1600 gross polluter After 02 sensor smog 15mph-- 6 pass 25 mph--9 pass Next day test only station smog 15 mph-330 pass 25 mph--1170 fail After my mechanic passed it i still had to go to a test only because of the gross polluter fail in the beginning. Also the Rpm's at 25 mph were 1900 by my mechanic and were 2900 by both smogs done at other places. My mechanic says his computer tells him when to shift so hes gunna look at my car and call the bureau to see who is testing at the right rpm Link to comment Share on other sites More sharing options...
RJSquirrel Posted July 1, 2010 Share Posted July 1, 2010 (edited) You need to work out the test station issue, but regardless of that: At high RPMs, your engine is leaning out. This points to dirty MAF sensor (clean it, CAREFULLY), clogged fuel filter or seriously carboned-up engine from running super-rich with bad O2 sensor. Your timing may also be advanced too far, but if its all carboned up, I'd verify the EGR is really working as its supposed to (I know your mech said EGR passed). In order of expense, I'd do the following: 1) Verify correct ignition timing (free, if you have a timing light) 2) Clean MAF sensor (~free if you are careful, $$$ if you are not and damage the sensor) 3) Clean EGR valve making sure it operates properly(~free) 4) Techron Fuel injector cleaner (~$8) 5) Replace fuel filter (~$20) 6) Sea-foam engine & Change oil/filter ( < $50 ) 7) New plugs/rotor/cap/wires ( < $100 ) Beyond this, you'll want to look at the cooling system, Idle air control valve(stuck open?), Replacement of EGR valve and all vacuum hoses, new catalytic converter, or intake manifold vacuum leaks. Good luck. Edited July 1, 2010 by RJSquirrel Link to comment Share on other sites More sharing options...
Jacobg Posted July 1, 2010 Author Share Posted July 1, 2010 The mechanic cleaned the maf and replaced the 02 sensor so its not those. Link to comment Share on other sites More sharing options...
Jacobg Posted July 8, 2010 Author Share Posted July 8, 2010 Okay. so the mechanic tested it again and passed on what the machine told him. He called the bureau and it said that every other time the car was tested at 2k rpm and for some reason the test only tested at 2950. Any people in Ca know what rpm their smog was ran at for 25 mph Link to comment Share on other sites More sharing options...
RJSquirrel Posted July 8, 2010 Share Posted July 8, 2010 Jacobg: Is your Pathfinder a 5-speed? Could this be the difference in being on the dynanometer in say, 2nd gear, vs. 3rd? Link to comment Share on other sites More sharing options...
Jacobg Posted July 8, 2010 Author Share Posted July 8, 2010 yes it is a 5 speed. the test only said they werent suppose to up shift and the mechanic says to up shift. Link to comment Share on other sites More sharing options...
Jacobg Posted July 11, 2010 Author Share Posted July 11, 2010 Anyone know waht rpms they were smogged at for 25mph. Takin it to the referee on tuesday thinking i might seafoam my engine before i go. Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now