chris53378

Well the non-foulers got rid of the codes: p0420/430 but now I am getting a p0021 which has something to do with the camshaft and VVT sensor. Every time I fix something on this car another thing pops up ?. Any suggestions? I know it can cause damage if it's not tended to in a timely manner.

Alright so the dealership had a tough time with this one as well but I got my car back a couple weeks ago so here is a brief summary of why they think this happened and what brought the pathfinder back to life: - Installing aftermarket sensors (MAF and IAC) led to some sort of shorting out in the ECU after some time - I bought a used ECU from a totaled pathfinder for $140 (as per the head mechanics recommendation) and payed about $500 for a stock MAF and IAC valve - They programmed the 'new' ECU to my vehicle and now it runs great! Total Cost: roughly $1000 A day after getting the car back I received both a p0420 and p0430 and seeing as I don't have the money to get new O2 sensors or catalytic converters I am going to buy some defoulers and see if I can get rid of these codes Once again thank you to everyone who chimed in on this post! although I wasn't able to figure it out on my own y'all helped me eliminate a lot of potential causes.

Well after Testing the IMMU and seeing that it has power and is communicating with the ECU it appears I may have tripped the NATS so I'm getting the car towed to the dealership this week because I don't have the CONSULT-II to diagnose the specific issue. Hoping I don't have pay an absurd amount of money to get this fixed. I'll be back with a diagnosis after we've resolved the issue. I greatly appreciate everyones input, definitely helped narrow things down!

Ok so I was wrong about the source of the buzz... it's coming from the transmission, sounds like it could be a faulty solenoid but now I am wondering if this would have anything to do with the park neutral relay being faulty (I did not get a code for it but I've heard they go bad after awhile and I don't know if it has ever been replaced). There is no spark either! Could this have anything to do with park neutral relay or the anti theft mode? both of my keys cause the security light to turn solid red once the ignition has been on for 3 seconds but I don't know if it has always been like that because normally I would just start the car right away (not wait three seconds to see if the security light turned on). An unprogrammed key turns the security light red immediately after the ignition is turned on so im wondering if that 3 second difference is significant.

I had to replace the starter 3 years back but the buzz is coming from above the location of the starter, I'm gunna try to see if i can pinpoint its location but no promises.

Unplugged the ABS and rechecked all the fuses and the problems persisted. Swapped the fuel pump relay and nothing happened, I don't believe its a fuel pump issue because when I did get it to run the other day (before doing the Idle re learn process) it was flooded. Going to buy a spark tester today so I'll get back to y'all with what I find.

@colinnwn Thanks for your suggestions! There is continuity between the engine ground these sensors are connected to and the sensors themselves and the battery connection is fine. Do you remember where the buzzing noise was coming from? For me it appears to be coming from the the passenger side, halfway down the engine bay, back toward the firewall which is no where near the IAC.

@fleurys I did open the ECU when I changed the IAC because I had heard the horror stories of people burning out that module and paying all that money for a new ECU. Nothing looked out of the ordinary, no cracks, no burns, and the car ran fine for quite awhile after changing it. Thank you for the response!

Hello! My 01 LE pathfinder will turnover but will not start and there is a buzzing noise coming from the passenger side when the ignition is in the ON position (Buzzing noise STOPS when gas pedal is floored). I have searched through forums for hours and cannot seem to find anyone who has managed to resolve this issue. What happened leading up: 4 months ago I was on a three hour drive and about half way the car shut off on the highway. I got a P0100 so unplugged the MAF sensor and plugged it back in (I had replaced it about a year earlier; thought maybe it had gone bad again) and the car started up and drove fine for the rest of the way. Two days later the same thing happed again and then the problem went away for a couple months. A couple weeks ago my car died at a red light and this time my MAF trick didn't seem to work, I got a P0100 and a P0505 this time (IAC has recently been changed). The car would start but not stay on, luckily I was close to home and I made by feathering the gas to keep it running. How I've tried to fix it: Downloaded the ECS repair manual, and turns out the MAF, IAC, and one of the crankshaft sensors were not getting proper voltage. They all traced back to the ECM relay so I changed that today and the engine still wouldn't start. Then I found that 7.5A fuse for the one of the engine coils was blown and after replacing it all of the the error codes went away (P0100, P0505, and P0335) and THE BUZZING STOPPED! The sensor harnesses were getting proper voltage and after doing the Idle relearn process I got the car to stay on. I had taken off the harness to the ECU connector during the diagnosis process and needed to put it back on. I turned the car off, disconnected the ECU, put the harness back on the connecter, connected the ECU, put my dash back together and went to turn the car on to go get gas but THE BUZZING RETURNED! ? Car is back to turning over but not starting, sensor harness are back to their inadequate voltages, and the buzzing persists while the ignition is on except for when the gas pedal is pushed to the floor. I've checked fuses and other relays but can't find the issue here. This car is my first car and I love it but its driving me crazy (no pun intended). Any suggestions? Edits: - I should also add that the security light comes and and stays solid red 3 seconds after I turn the ignition on (this occurs with both of my programmed keys). I have 2 other unprogrammed keys that turn the security light solid red immediately after turning the ignition on. Not sure if this is an indication of the Anti-theft mode or not. - BUZZING IS COMING FROM TRANSMISSION