supertool

Hi. My check engine light comes on with these codes that I self diagnosed.
9-3 EVAP Canister vent control valve
3-4 Knock Sensor
This happens after about 20 -30 minutes of hiway driving. During the week, I drive city streets, so it doesn't happen. Nothing noticeable changes in engine tone or anything. I tried it with different gas.
I keep resetting it. Well I was down in L.A. so I had to get back.

My mods are listed below.
Anyways, has anyone else had these symptoms, and what's a fix for these?
Thanks.

supertool

Thanks, but I don't think that's it.
EVAP canister codes have to do with the way gasoline fumes are handled, not AC.
But I need to know exactly what the problem/solution is.

kchida

many people believe that the knock sensor code accompanies other codes such as the O2 sensors, etc. I think this is incorrect. the 0304 knock sensor diagnostic trouble code is the only one that does not cause your check engine light to go off. (according to my '98 factory service manual) so you can have a malfunctioning knock sensor and not know this for many miles. I got my knock sensor for approx. $140 and was easy to replace (I used a universal joint and a long extension). I'd read up on previous post for tips on replacing your KS. I tried to get it professionally repaired but they quoted me $400-$500 because they wanted to take apart the intake manifold to access the KS. Although Nissan recommends this, I dont think removing your intake plenum is necessary in order to get to the KS. A malfunctioning KS is not a great big deal. It may affect your gas mileage and engine performance. most likely you wont notice a difference. however, it is something you want to fix.

like your said, 0309 DTC is EVAP canister vent control valve(circuit). this valve is located on your EVAP canister next to your rear left tire (looks like a metal box). either the circuit between your valve and the ECM is shorted/open, or the actual valve is malfunctioning. you should get it checked out to see if its a problem in the circuit or in the valve. if the valve is malfuncioning then you can simple pop in a new one in place of the old one. like the KS, i dont think this problem is too serious either. you might want to take care of the EVAP problem first to see if KS DTC goes away. you never know. hope this helps.

supertool

And see if it's the circuit of the valve? I'd rather not replace the valve unless it's broken. Also, replacing this valve would any gas be leaking out?
Could a JWT popcharger cause knock sensor to go off?

supertool

I need to know if a DIY mechanic can fix this, and how.
Or do I need to take it to the shop.

supertool

bump

Rutnick

Once you got the old KS removed, how did you get the new one threaded? I am not going to be able to get my hand in there.

kchida

shoot. your gonna have to remove your upper intake plenum unless you can find someone with smaller hands that can help you out. i forgot exactly how much space you have to work with, but you can try putting the head of the nut in some flexible rubber tubing and work it in there(much like spark plug installations). then finish it off with the extention and joint. i never had this problem so i cant tell you how to get around it except to take apart your intake.

supertool

What do I gotta do with the evap canister?

Rutnick

I never thought I had large hands until I tried getting to my KS.

supertool

I just took a look at the knock sensor, and I don't think I would be able to fit my d!ck in that space, much less my hand
I guess I gotta get some anorexic friends in a hurry

supertool

BTW, does anyone have the part number for the knock sensor?
Thanks.

maxwillden

Sorry about the Evap A/C connection... Bad info from the local mechanic...

Anyway, since you have a 96 SE, I may have the answer to both of your questions...

I have a 96 Maxima SE with 87k on it, and was having the same trouble codes...

See this link for more information:

http://forums.maxima.org/showthread....557post1043557

By the way, I've heard that the O2 Sensor, and the Knock Sensor trouble codes may be connected, and that is why you're getting the 0304 Trouble Code... Get your O2 Sensor replaced first (hopefully under the recall) and see if it fixes your KS problem.

sinewave

I just read in AAA magazine that overfilling gas tanks can set off all kinds of EGR and vapor control error codes. If you are in the habit of topping off the tank when you fill up, try discontinuing the practice to see if it ends the canister error code. I doubt, however, that it has anything to do with the knock sensor code.

maxwillden

You are ABSOLUTELY correct! The Knock Sensor has nothing to do with the canister, or EVAP system. Nor did I claim it did. What I did claim, based on the dealers expertise is that the Knock Sensor may be related to the O2 sensor... According to the dealer, a bad O2 sensor could be related to a knock sensor warning... Maybe they're wrong...

SuDZ

I did not think my hand was gonna fit either and I was right so I resorted to more drastic measures. I went in the house after messing iwth it forever trying different tools etc. I soaped up my arm really good up to the elbow. Then I went back outside without washing off the soap and help in one hand the knock sensor and the wrench with a socket on it. Unplugged the green harness in fron of the whole for some space. I looked at the hole and said to myself "Your either gonan get in there or break your hand trying" So I arched back and punched as hard as I could at the thing driving my hand in(kinda hurt my pinky finger a bit) and got sliced from the wrist to the forearms on a stupid metal tab .... but I was in. Worked on unscrewing the bolt etc in there the whole time cutting my arm more on thattab but did it. Then took about 10 minutes to get my hand out of there since it was kind of stuck but finally it was working.

So you can do it with big hands but the stakes get a bit higher hehe

SuDZ