Help!!!!!

[jarred15801]

Well i got the check engine light lastnight and did a diagnostic test on it today. I got p0302 code 2 times for cylinder 2 misfire, p0325 code 1 time for knock sensor circuit bank 1, and p0330 code 2 times for knock sensor ciruit bank 2.

Is the misfire just plugs or wires most likely? And the knock sensors a bad harness probably? What else could this stuff be? Help pleasee!!

[qship96]

Wires? Have you ever even Looked under your hood? There are no wires- coil on plug ignition system

Most likely you have a bad coil, as this seems to be a frequent problem on the Q41 series. Replace both knock sensors and harness, and anything rubber on the way to get to them {hoses,gaskets,etc}

[jarred15801]

this is the coil i'll need correct? number 1 on the diagram

http://www.trademotion.com/par...gid=2

can anyone find me a link to a place for the knock sensors and wiring harness for them because i dont see them on that site?

[maxnix]

You need to read a few threads on the stumble at idle.

You need to switch coilpacks, clear the codes, then see if the fault follows the coilpack or not. About $173 from Joe.

Be sure to study FSM.

Any maintenance history on fuel or intake system? If not, run some ISO-Heet and BG44K after cahnging out fuel filter and air filter before doing the above.
Modified by maxnix at 10:24 AM 4/14/2008

[jarred15801]

The motor wouldn't miss or stumble at idle. It would idle fine and the power felt normal when i accelerated quickly. The only time it would miss or stumble was between 1500 and 2500 rpms when id slowly go through the gear. it usually doesnt do it other then that. and as far as maintenance history i don't know? i just bought the car last week from a dealer. it's a 97 with 99k miles.

I have a list of things to do like differential fluid, oil and oil filter, radiator fluid, spark plugs, fuel filter, transmission filters and fluid,air filter, clean off all the O2 sensors, and bg44k in the gas. I plan on doing all that and clearing the codes and then seeing if they come back. if so ill switch the coil pack and see if it follows like you said above. Does that sound like a good idea so far?

[Q45tech]

Replace both knock sensors and their harness first thing so the diagnosis gets simplified with fewer known codes...............knock sensors can create the stumble you mentioned.

[maxnix]

as far as maintenance history i don't know? i just bought the car last week from a dealer. it's a 97 with 99k miles.

Return to your favorite service writer at the dealer and have them print out the Infiniti dealers perforemd service history. They owe you that.

[NightRiderQ45]

God, I'm blessed that my Y33 has been maintenance/problem free. There was a great owner before me and I'm still continuing the trait... Maxnix, what exactly does ISO-Heet do? It gets the water out of your fuel lines correct? Wally World has a 6-pack of ISO-Heet for $3 .

Is this a fluid that you add everytime you fill up?

[NightRiderQ45]

Any maintenance history on fuel or intake system? If not, run some ISO-Heet and BG44K after cahnging out fuel filter and air filter before doing the above.

Modified by maxnix at 10:24 AM 4/14/2008

According to BG 44k, you don't have to change out the fuel filter because it "suppose" to clean the fuel filter also.

[qship96]

According to BG 44k, you don't have to change out the fuel filter because it "suppose" to clean the fuel filter also.

Exactly how is BG44k suppose to disolve all the particles of metal, rust ,sand, dirt, etc trapped in your fuel filter? IT CANT

change fuel filter annually, it is less than $15 and easy to do yourself.

[jarred15801]

Return to your favorite service writer at the dealer and have them print out the Infiniti dealers perforemd service history. They owe you that.

It wasn't an infiniti dealer though. He only had the car on his lot for a couple weeks.

[jarred15801]

And what is a site that i can get the knock sensors and wiring harness from?

[NightRiderQ45]

Yeah, this is something that I need to do on my car, but I WONT do it myself though.

[maxnix]

God, I'm blessed that my Y33 has been maintenance/problem free. There was a great owner before me and I'm still continuing the trait... Maxnix, what exactly does ISO-Heet do? It gets the water out of your fuel lines correct? Wally World has a 6-pack of ISO-Heet for $3 .

Is this a fluid that you add everytime you fill up?

No car is maintenance free. There are only degrees of maintenance between abused and as new OEM.

It's difficult to know how much water is in the gasoline you buy. Try it in two straight tanks first, and if that improves anything, then back off to every other tank and see how that goes.
Modified by maxnix at 5:01 PM 4/14/2008

[maxnix]

It wasn't an infiniti dealer though. He only had the car on his lot for a couple weeks.

Then register your car with Infiniti Customer service and they will dictate the dealer service records to you. Wise owners never buy a car without reviewing these first. Helps point to where the Tech may want to look a little more deeply.

Every owner needs to have a relationship with a writer or service manager at the dealer.

[maxnix]

According to BG 44k, you don't have to change out the fuel filter because it "suppose" to clean the fuel filter also.

If you believe that, then you haven't read Q45tech's recent fuel injector posts. He uses BG44K more frequently than a priest uses wine. He had a nice goo from recently introduced ethanol.

[maxnix]

And what is a site that i can get the knock sensors and wiring harness from?

One of our prime sponsors if you will look at the NICO Sponsors on the right of your screen.

http://www.infinitipartsusa.com

Call them with your VIN

[jarred15801]

Then register your car with Infiniti Customer service and they will dictate the dealer service records to you. Wise owners never buy a car without reviewing these first. Helps point to where the Tech may want to look a little more deeply.

Every owner needs to have a relationship with a writer or service manager at the dealer.

Well i do know that the car was regularly maintained up to 70,000 miles with the warranty. From 70,000 to 99,000 i couldn't find any paperwork on it in the car. But thanks i will look into that.

[maxnix]

Like the cliché, it's out there.

[jarred15801]

Well the day after the check engine light came on it went back off. Dopes that mean the problem went away? And becasue it gave the knock sensor codes does that actually mean the sensors are bad? or couldn't it just be that the engine had knocking?

couldn't the misfire have caused the engine to knock?

[qship96]

chances are the light will come back on-sounds like a coil going bad

knock sensor code only shows if sensors or harness are bad, not that the computer knew the engine was knocking.

bottom line , you still have both problems to deal with......replacing knock sansors and harness and tracking down the intermittant cylinder misfire which is most likely a coil going bad

[jarred15801]

Okay thank you very much

[maxnix]

couldn't the misfire have caused the engine to knock?

A Nissan tech told me almost anything will also set a KS code, so they fix everything else first, erase teh codes and monitor it.

[jarred15801]

If the knock sensor doesn't detect engine knocking then what is the point of it?

[Q45tech]

"A Nissan tech told me almost anything will also set a KS code, so they fix everything else first, erase teh codes and monitor it."

He better go back to school and study OBD2 on how KS work and set codes.

The FSM is pretty clear that you don't depend solely on codes but immediately proceed with series of diagnostic test to measure the sensor which applies to the code.

Easy to check resistance of KS [on the engine] to decide how bad they are cracked and when the intermitent codes will become continuous [always happens eventually].

[maxnix]

To clarify, if there is a cylinder misfire code, quite often it will also throw a KS code according to him. So standard procedure is to address all other codes first, then the KS if the code returns with no others.

[Q45tech]

Even in OBD2 the KS code is only activated when the KS doesn't pass the start up or periodic resistance test check. The KS code has nothing to do with KNOCK.

Note it says knock sensor not engine knock.

The ecu just has a fill in the blank space for a number from KS microprocessor +3. +2. +1, 0, - numbers to -15 degrees[in hex# or oct# of course]..................it just adds that number in to arrive at a final number of advance degrees.

[maxnix]

Well, when I was getting a cylnder misfire code and a KS code, I no longer recieve any codes after faulty coilpack replaced and ECU reset.

Always had cylinder code paired with KS code before repair. OBD II.