HELP!!!

[ydlee]

I have a 1999 QX4 and I originally installed a aftermarket cone air filter and everything was good until my stupid *** installed a after market tube. So I installed a chrome aluminum aftermarket tube without connecting the two hoses and the car would not start. So I re-installed the factory tube and kept the cone filter on now the car doesnt start unless I press the gas and have to have the gas press over o rpms other wise it stalls. I know I am an idiot. Any suggestions? I tried unplugging the battery and I tried having the gas pressed at different rpms from 3k all the way down to 250 rpms but when I let go the rpms go to zero and the car dies and has check engine light. Is there a way to clear the ECU besides batter disconnect? Please help!

Modified by ydlee at 12:27 AM 9/17/2005
Modified by ydlee at 12:29 AM 9/17/2005

[quiksilvia]

are u just disconnecting then reconnecting right away or waiting? if u leave it off and reinstall everything back to stock and then reconnect it after like 5 mins it should work

[NISTECH]

You have a very large air leak. Either those hoses are swapped or you have a hole in the intake tube or rolled rubber at one of the joints.

[ydlee]

So I took it a local gas station shop, only reason because I was afraid to go any distance the fact everytime I come to a stop I have to keep it above o rpms or else it dies on me. Anyways they did a diagnostic and it was nothing because I cleared it with disconnectin the battery overnight and they ended up tighting up the throttle body or something and now the car turns on fine but the engine light came on and I took it to autozone and had some codes of P05050 and P0325, which are idle malfunction and knock sensor.

[ydlee]

Should I check the intake tubes if there is a leak still? Because I figure tighting the throttle really fixed the problem of starting up.

[NISTECH]

he tightned the hose I was talking about where it connected to the throttle body.

[ydlee]

He tightened the throttle but it still had engine leak. I took your advice and checked all the piece of intake there was a split or crack in the rubber arm connected to the plenum. The rubber is hard and old so that is what must of caused all this. Thankyou your the man!! Do you by chance know where I can buy this piece? The rubber arm connected to the plenum and the plastic intake tube?

[ydlee]

He tightened the throttle but it still had SES light. I took your advice and checked all the piece of intake there was a split or crack in the rubber arm connected to the plenum. The rubber is hard and old so that is what must of caused all this. I used another rubber to cover the crack temporaryly and cleared my ECU by disconnecting the battery and drove around for 20 mins and no SES. Thankyou your the man!! You know you stuff! The people at the gas station didnt even check that part. Do you by chance know where I can buy this piece? The rubber arm connected to the plenum and the plastic intake tube?

[NISTECH]

Try one of our dealer sponsors. Or you can try to locate a cold air intake like you initially tried but one that has the PCV and Idle air control hose fittings.[ those are the 2 hoses coming off of the plastic tube]

[ydlee]

What is this called the thing I circled in yellow? And do you know where I can find this part for replacement? That is what was cracked. Thankyou. I really appreciate it.

[NISTECH]

Intake boot. at the throttle body.

[ydlee]

Alright Sorry to bother again, I replaced the intake boot bought part at Nissan dealer and cleared ecu with unplugging battery. The SES light still comes on with the codes P0505 and P0325 any ideas? Should I just put the OEM airbox back in and take off the cone filter?
Modified by ydlee at 9:15 PM 9/17/2005

[NISTECH]

Have the codes cleared by autozone or something and redrive the vehicle to see if the code comes back. Your not suppose to be able to clear codes on OBDII vehicles by disconnecting the battery. Have them cleared with a scan tool. BTW the p0325 code will not turn on the light. I suspect that is a problem with an open circuit to the knock sensor. It is a real pain to change on your truck too.

[ydlee]

After clearing codes do you think I am better off with the stock air box and K&N drop in air filter? Or is the cone filter better? Do believe the cone filter even gives more horsepower vs. stock air box with K&N drop in filter?

[NISTECH]

I dont really think you will see an enourmous gain. In theroy I am sure the cone promotes better air flow as the box is not a straight shot to the intake tube so you get some turbulance in the intake airflow.

[ydlee]

Ok this morning I went to start the car the (QX4) and it had problem even starting and after a couple of attemps the rpms catched at 700 rpms and finally were stable. And I turned off the car and started it up again it had a couple of rough starts but it ran fine after that. Do have any ideas? So I decided not to even clear the codes because there is something wrong, I have to take to a shop. Do have any ideas?

[NISTECH]

the code may be legitamate for the idle control then. It needs to have a functional test done with a scan tool to see if it is operating right.

[ydlee]

Yes I tested the car with a OBD scanner and came up with p0505,p0325 should I clear the codes SINCE I replaced the air intake boot and it starts up rough/stalling? Is the car starting up rough/stalling because the code is still present and thinks there is something wrong? And the gas station did adjust something on the throttle by adjusting it and now since the leak was fixed is this affecting the computer?

[NISTECH]

No I mean there is a functional test you can do with the nissan scan tool that will activate the idle control valve to test it, not simply pull codes.

[ydlee]

Well I finally took it to a mechanic with the codes P0505 and P0325 which are for the knock sensors, idle valve control. The shop gave me an estimate with parts and labor for $1400 ridiculas huh. $700 for parts and $700 labor. I walked out on them because on the net or ebay the prices are cheap. Anyways I took it to an honest mechanic shop and they are charging me for parts and labor for $783 not bad from $1400.

[NISTECH]

The knock sensor will not cause the check engine light and I suspect a lrage part of that repair if for that. The Knock sensor is located in the middle of the engine under the intake manifold, Which requires heavy labor. You should have inquired about how much just the 505 repair would be. The knock sensor will not hamper performance all that much, certainly not enough for you to notice. The idle valve will however have very adverse effects on the engine.

[ydlee]

What would happen if I dont do the repairs on the knock sensor or I mean replacing it? I might have a chance to cancel the order on the knock sensor and it will save me some money on only repairing the idle valve.

[NISTECH]

You timing will not advance as far as it possibly can during hard acceleration. The knock sensor is there to prevent pinging on hard accel, It allows the ECM to "see" if the engine is preigniting. When the knock sensor is "playing along" [working] The ecm will allow the timing advance to go as far as possible until it sees a signal from the sensor then it trims it back slightly. If the knock sensor is not "playing along" [ has an open circuit] The ecm reverts to a still helpful advance but limited. So to sum it up. You might not get quite as good of quarter mile times at the track as you would if say it was working.

Basically if you not a die hard performance buff you wont hardly notice it. Now I must warn you though if you do start experiancing frequent events of pinging you may want to look into getting it done. Chances are though if you are running the recommended premium gas you probably wont experiance it.

[ydlee]

You dont by chance know the hub size for a 1999 QX4? I bought rims with a hub size of 106mm will this be a problem?

[NISTECH]

This I dont know. You may wanna try posting in the tires and suspension forum.

[ydlee]

NISTECH is this a good deal for $1650

My previous repair:

Knock SensorIdle Control ValveADDED ON:Timing BeltWater PumpValve Cover/GasketsTune Up90K Service

[NISTECH]

Yea thats a good deal. I hope your at a dealer where the person working on your car knows what he is doing? Also being very very familier with your vehicle will notice if something is not right. Where as a tech not familer with your car and quite possibly nissan wouldnt notice it.