Nissan Versa Forums banner
1 - 20 of 30 Posts

·
Registered
Joined
·
19 Posts
Discussion Starter · #1 ·
Sorry if this is in the wrong section but....


Hello everyone,

I am no mechanic but think that I might be close after all of my issues with my 08 versa sedan non cvt. OK bottom line is that my fuel trims are crazy. So while driving the trims are normal but when stopped at a light they will usually run rich up to max measurable limit of +25%. The car will run fine but I do smell gas. If I am driving in the city with stop and go traffic the rich mixture seems to pile up and then force the car to stall. But sometimes it runs super lean with -25%. Either way the car will stall. It does start back up with a longer than normal crank. Sometimes the car will want to stall. RPM's will dip low then it will correct with high RPM. Then when I turn off the car I can hear fuel popping in the exhaust also sometimes while driving I can hear it pop. It does have a CEL for a catalytic convertor but I would think its from the rich mixture. So now the list of parts thrown at this problem....remember I'm no mechanic and im at my wits end so I have tried anything I could think of.

Fuel pump
Checked all injectors and replaced 1 just to make sure. Car ran perfect for 1 day.
Fuel rail.
checked for any vacuum leaks
fuse relay box (Holds fuel pump relay)
all filters
purge solenoid
both o2 sensors
serpentine belt
all coils
all plugs
coolant temp sensor
cleaned throttle body multiple times


I am missing some things im sure but please!!! help me. I know that this has to be an easy fix because when the car runs properly its smooth as glass. The car has 216k but still pretty strong. At this point I refuse to lose.


John
 

·
Registered
Joined
·
19 Posts
Discussion Starter · #5 ·
Do you know what the codes are that are stored in the ECU? May be no help but who knows. I know P0420 is a catalyst codes and I think think there are a couple others but was wondering there are any codes that might also present other problems.
That is the only code that comes up P0420. I did some more driving with the scan tool tonight and the upstream o2 sensor will read steady at about 2.2v until I let off of the gas and then it will go all the way up to about 5.0v for about 3-5 seconds then return to normal. At the same time the short term fuel trim will remain normal until I come to a stop then it will fluctuate from +8% to +25%. Once I take off it will normalize to +/- 3%. I did some more research as I am running out of parts to replace but I did see that a malfuntioning PCV valve that is stuck open would act as a vacuum leak. That is the next step I think unless something else comes up. My scan tool does see an EVAP leak but it has not triggered a code. Fingers crossed.
 

·
Registered
Joined
·
393 Posts
the PCV valve is actually quite easy to replace. You have to disconnect a hose in the engine compartment (passenger side) and then pull and replace the valve. Let us know!!
 

·
Registered
Joined
·
19 Posts
Discussion Starter · #7 ·
It's already ordered and should be here in a few days but if anyone else has any thoughts please send them my way. If this actually fixes the issue I don't know if i'm going to be pissed because it was so easy and so cheap or break down in tears because i'm happy that it was so easy and cheap to fix. I just took the most expensive route possible to get there.
 

·
Registered
Joined
·
393 Posts
It's already ordered and should be here in a few days but if anyone else has any thoughts please send them my way. If this actually fixes the issue I don't know if i'm going to be pissed because it was so easy and so cheap or break down in tears because i'm happy that it was so easy and cheap to fix. I just took the most expensive route possible to get there.
well....if this gets it fixed it looked at it in the happy mode: you replaced a bunch of stuff that now you know it's in pristine condition!

This should get you going for a long time :)
 

·
Registered
Joined
·
466 Posts
The signal from the upstream 02 sensor should constantly be oscillating between 0.1v and 0.9v giving it an average reading of approximately 0.5v. 0.1v is lean 0.9v is rich. According to what you have posted your always running lean which makes me think you have a vacuum leak somewhere. Does the intake have to come off to replace the plugs on your Versa like it does on mine? If so, the intake gasket should have been replaced when the plugs/coils were changed. If it wasn't changed that could be the source of you vacuum leak.
 

·
Registered
Joined
·
19 Posts
Discussion Starter · #10 ·
The signal from the upstream 02 sensor should constantly be oscillating between 0.1v and 0.9v giving it an average reading of approximately 0.5v. 0.1v is lean 0.9v is rich. According to what you have posted your always running lean which makes me think you have a vacuum leak somewhere. Does the intake have to come off to replace the plugs on your Versa like it does on mine? If so, the intake gasket should have been replaced when the plugs/coils were changed. If it wasn't changed that could be the source of you vacuum leak.
Yes the intake needs to come off but I did not replace the gasket. When I was looking for the leak I did try to test that area but did not find any leaks there. I will go down that road after I replace the PCV valve. I am hoping for a miracle with that. Thanks for giving me the idea!!! Much appreciated.
 

·
Registered
Joined
·
393 Posts
The signal from the upstream 02 sensor should constantly be oscillating between 0.1v and 0.9v giving it an average reading of approximately 0.5v. 0.1v is lean 0.9v is rich. According to what you have posted your always running lean which makes me think you have a vacuum leak somewhere. Does the intake have to come off to replace the plugs on your Versa like it does on mine? If so, the intake gasket should have been replaced when the plugs/coils were changed. If it wasn't changed that could be the source of you vacuum leak.
good idea!

what gasket are you referring to, between these two?

thanks

I might replace the plugs too soon, so it's good to know.
 

·
Registered
Joined
·
466 Posts
Another thing you might test is the cam position sensor. I'm sure there's a way to test it. The procedure can probably found online. The cam position sensor plays a roll into when the injectors fire and can cause all sorts of drivability problems including random stalling.
 

·
Registered
Joined
·
19 Posts
Discussion Starter · #16 ·
Another thing you might test is the cam position sensor. I'm sure there's a way to test it. The procedure can probably found online. The cam position sensor plays a roll into when the injectors fire and can cause all sorts of drivability problems including random stalling.
The cam position sensor might be the next attempt but the car doesn't just shut down like I think that sensor would make it. It will sputter and then eventually die.

Just an update on the piece of Versa. I have put in the PCV and it did seem to help with the stalling (for 1 day). It ran much better without the flutuation in RPMs and stayed pretty steady at about 900 rpm when idleing. The idle was rough but didnt flutuate like it had in the past. I drove it about 300 miles for the day without issue. That evening I did the manual idle relearn as instructed in hopes of fixing the rough idle as it was still running rich but it was more steady and not as rich as in the past. The next day I went to the gym and when I was leaving I pulled out of the parking spot and by the 1st stop sign it had stalled. It was different this time as it stalled while I was in motion and not stopped for a light. It started right back up but with a flutuating idle (FML). As I stated before it does have a CEL for a catalytic convertor but I think it is just not burning off fuel like it should and does not seem to be plugged. I do seem to have a slight loss of power but it is throughout the powerband and highway speeds do not seem to be limited as I was easily able to reach 80MPH on the highway. I am also contemplating boring out the convertor as it is already bad and see if it will alleviate the issue. It is always possible that it is partially plugged. I will try to attach recent picturs of my car data to see if anyone can shed some light on this. The data is from a cold start with about 10 mins of idle. The CEL had been cleared also. If the pictures dont show please let me know.
Finger Electronic device Text Technology Display device
Finger Electronic device Text Technology Display device Finger Electronic device Text Display device Technology Finger Electronic device Text Technology Display device Finger Electronic device Text Display device Technology Finger Electronic device Text Technology Display device Finger Electronic device Text Technology Display device Finger Electronic device Display device Technology Electronics Finger Electronic device Display device Text Technology Electronic device Product Display device Text Technology
Finger Electronic device Text Technology Display device
Finger Electronic device Text Display device Technology
Finger Electronic device Text Technology Display device
Finger Electronic device Text Display device Technology
Finger Electronic device Text Technology Display device
Finger Electronic device Text Technology Display device
 

·
Registered
Joined
·
19 Posts
Discussion Starter · #17 ·
Another update. I know that my scan tool says that there is an evap leak but I have no codes for it. So I have looked into that. Ive learned that the popping noise that I thought was excess fuel burning in my exhaust seems to now be pressure releasing from my fuel tank. I put positive pressure into the tank via the evap system and I can reproduce the sound. Now what??? It seems that its not releasing the pressure like it should. Even when the evap system is taken out of the equation. I thought possibly the pressure release at the fuel filler cap was clogged but I was able to blow air through that. All of the purge valves and the valve on the canister are good. I did try and test the valve on the canister but it does not seem to close when car is started for a leak check. What else should I check? Still all a mystery for me.
 

·
Registered
Joined
·
19 Posts
Discussion Starter · #18 ·
Anyone have any ideas. Pressure builds up in my fuel tank. Pressure valve has been replaced. Evap canister has been replaced. purge valve replaced. ANYONE PLEASE????
 

·
Registered
Joined
·
342 Posts
Check the voltage at the EVAP pressure sensor. It should be about 4.1v with the car running.

High fuel trims at idle that get better when holding some rpms shows a vacuum leak. Watch stft while spraying brake cleaner at suspect areas, or using unlit propane.

On these, the front sensor is an A/F sensor that should read 2.2v most of the time. Less than that is lean, more is rich, but these respond much quicker than o2 sensors and go right back near 2.2v. You can create a vacuum leak by pulling a vacuum line and create a rich condition by inducing unlit propane I to the intake. The A/f and o2 sensor should react.

This sounds like a maf sensor issue, but it's hard to say without seeing/testing other stuff too.
 
1 - 20 of 30 Posts
Top