man i keep getting a check engine light for an evap leak, i get it reset and it goes away for about 1-2 weeks and comes back, i get good gas mileage, the gas cap looks fine, what else should i look for, thanks guys

 

I have the same problem 0304(knock sensor) and 0111(EVAP control system/FLOW). I reset the ECU and get 0505(No Failure), a day later the same code comes back. Any help would be appreciated....thank you

 

Check for a vecum leak in your evap system

 

you think i shoudl replace the gas cap ayways

 

how do i check for a vacuum leak?

 

i dont know what that black box is called, but its on the opposite side of the exhaust and it has a bunch of hoses connected to it, well the really long hose that goes around to the back of the box than connects to some circular canister than has like a exhasut hose, well at the begining of the hose there was no clamp so i pulled the hose off without any effort, i replaced the clamp hoepfually this will fix my prob but the light is still on ill let it go away on its own

 

Ya...I've had EVAP problems too. Past two times the light came on, it was EVAP canister. This last time it came on, I left it alone for a month, and a few days ago the light just turned off..either its fine or it got impatient.

 

The black box is the Evaporative Canister...... Its filled with charcoal and it traps gasoline vapors from the gas tank

 

Now that you guys mention it, I believe thats the code that nissan pulled when my dad took the car in for sceduled maintinence. I never actually did anything about it, cause they didn't seem to think it was a really big problem. What exactly are the negative effects of EVAP problems? seems like my car is running perfectly .. well minus my sticking calipter but .. yah

 

You wont notice much of a difference in performance or the way the car runs....

 

my car runs fine too, i just want to get the light out cuz its annoying as hell

 

This last time I had the check engine light, it was the 3rd time. I didnt check them though. The last 2 times were EVAP leak. I was planning on taking it to the mechanic, but 2 days ago it just...went away. I'm so happy.arty: