# EVAP system, help pls...



## diamond (Oct 24, 2002)

I have a 98 altima GXE, 63,000km (about 40k miles)

I have found flash codes 0309, 0705 and 0304 from my SES light, which I have diagnosed as:

The EVAP canister vent control valve,

"small leak in EVAP" system, and

Engine Knock sensor tripped.


Does anyone know how to fix these items?

Is it something I can do myself? I have a Haynes manual, but it doesn't show any pics for the 98-01 models...

Thanks,

diamond


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## Asleep (Jan 19, 2003)

for the first two, if i remember right, you have to get a vacuum tester and test the cannister. for the knock sensor, it hardly ever goes bad and thats a good thing, at 275 bucks at autozone, its hardly something you wanna replace "for the hell of it". you know? for the knock sensor, remove the connector and spray both sides of the contacts, male and female, with an electrical contact cleaner or with brake parts cleaner. it usually gets oil or dirt on it and quits registering. while the plug is disconnected, get a wrench and make sure the sensor is tight. theyve been known to loosen up and trip a code. this usually takes care of it. otherwise, check your timing, get better gas and reset the ecu.


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## BORNGEARHEAD (Apr 30, 2002)

The knock sensor will not set off a c.e.l. If you have a code for vent control valve and small leak, chances are that you need to replace the vent control valve. Behind the driver side rear wheel there is a charcoal canister(black box). On the front of it is your vent control valve. To remove the valve remove the 2 10mm bolts, electrical connector and hose. To test the valve just run 12v of power to the valve. As you reverse the leads, you should be able to hear the valve "pop" back and forth. A lot of times in the northern states corrosion builds up on the valve and does not allow it to open and close causing the leak. Look inside the valve and look if there is rust building up on the plunger. I have seen a # of those go bad on a lot of Nissans. Let me know what you find out. Hope this helps.

D.J.


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## diamond (Oct 24, 2002)

Ok, I dound the evap vent control valve- it looked a bit corroded.

Replaced the valve- but left the canister in place. I hope this works!

I was looking at my warranty- and it says that in places where there is a yearly emission testing program, the valve would be under the 8 yr/130,000 warranty! I asked my dealer about this, but it was not applicable where I am. 

Whose rather dumb idea was to put a valve behind a wheel well?


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## altikris (May 30, 2003)

cars arent meant to last forever my friend.


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## diamond (Oct 24, 2002)

it's a NISSAN, it should last forever!

well, at least gimme 10 to 15 years!


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