new member w/2001 Quest with questions about obdII codes

[rustysmith52]

Hi everyone, Rusty here... hope someone can help. I've got a 2001 quest with 117,000 miles on it. Had very little trouble with it, but I've got the service engine light. Took it just to see what it was to Autozone and the codes are 0325 (knocksensor) and 1440 (evap small leak). I have the Haynes manual but where it shows the charcoal canister to be located, mines not there and I can't locate it. Also, the connector that you can jumper across to clear the codes isn't where its supposed to be nor is the connector for the knocksenser where it's supposed to be. Can anyone share any info on where these parts are located. Also do you think it would be worthwhile to take this car to a nissan dealer and let them put there machine on it to further diagnose it.

Thanks for any help.

[SteveTheTech]

Hey there Rusty Welcome to Nico.

The knock sensor code will not set your CEL, so your primary DTC would be the evap small leak.

First thing to check is the gas cap. If it wasn't tightened properly a code will set. If that gas cap is tight and the seal inside is in good shape than testing will be needed. Evap testing can quickly become a PITA so paying the 1hr diagnostic fee at the dealer may give you an answer with the minimum amount of work.

The operating pressures in the evap system operate at a fraction of 1 psi so finding a leak is not easy.

Click Here for a link to the factory service manual. The EC.pdf is the engine control section.

The "stealership" is not always a ripoff and they should be able to resolve this once and for all, or at least be able to tell you what's wrong.

Good Luck

[Q45tech]

The VALUE of dealership or the very rare Nissan specialty independent shop is pure and simple VOLUME, EXPERIENCE, and parts inventory.When a technican works on hundreds of identical same year models, he or she gets GOOD at it! Learning all the symptoms and solutions to get efficient at soving the problems fast.

A GENERIC shop may not see your model even once per year, it all depends.

For a specialist the vehicle speaks to the technican in secret subtle ways.

But everyone starts the same, with reading OBDII codes, then looking them up in FACTORY SERVICE MANUAL or All Data and follows the step by step written proceedures to narrow things down.

Just like a dealer parts department KNOWS what breaks and needs replacement, the independent doesn't have a clue.

We have a data base cross referenced by year and model of Infiniti for every part we have purchased in the past 9 years.

I can estimate pretty accurately when [on average] a part will fail and need replacement and what the average life is [at least for Infiniti in the South].

If you don't have a lower cost TRUSTED Nissan Specialists available the dealer is the best bet.

[rustysmith52]

Thanks for the reply. I pulled the battery so I could get to some of the connections that I thought was the one to clear the codes. I found the evap cannister and made sure everything was tight and the hoses were ok. I also checked the connections for the knock sensor. I put everything back together and no check engine light. I had disconnected the battery before, but the light came back on. Its been about a week and still no light. I'll probably go by autozone and see if the knock sensor code is still there