Throttle Body Replaced, now Idle is high (950)

[Laker4ever]

I have a 2003 Nissan Pathfinder SE. VQ3.5 AT with about 76,000 miles.
Never had any issues since day 1, only oil and filter changes.
Last couple of weeks i had days where after starting the vehicle, pressing the Gas pedal would do nothing. Turning off the engine and turning it back on, would fix it, and it would drive great. Then came a (CEL) check engine light and i read a P1121 code (throttle body actuator). So i cleared it couple times, and it came back after a week or so. Two days ago, i started the engine and it would die right after starting. Pressing the gas pedal when starting didn't change a thing.
So I was able to buy a new HITACHI replacement part and installed it with a new gasket. I torqued it according to specs of about 70 inch/lbs. The first time i started the engine, it stalled. Then i attempted to follow the reset sequence that i found on the web. (one was for 350Z, the other for Altima), they were the same. The last step of the reset (volume air adjustment) shows that the CEL should blink after the 20 second of gas pedal press and then you need to release the pedal within 3 sec of the light getting solid again. My CEL never blinked, it was always solid under IGN ON, ENG OFF. I cleared the old code P1121.
But still, after doing that, the engine starts well and only problem is high idle speed. I remember that in P or N and AC off, it was doing about 750 RPM, with AC slightly higher. Now with the new TB, in P and N it revs at about 950-975 RPM. At one point i got another CEL code of P0507 (High Idle speed) which make sense.
I've found that this issue is common on such TB replacement jobs, but i couldn't find a solution.
Is there a different reset scheme for the 2003 Pathfinder? Was that OK that i never got the CEL to blink towards the end of the reset sequence?
Is that true that the ECM will eventually tweak the idle speed down by itself?
Or do i have to go to the dealer for them to connect it to the computer (Consult II) to have it programmed correctly?
Thanks much for the feedback.

[Towncivilian]

Try following the three relearn procedures found on page EC-81.

[Laker4ever]

Thanks Towncivillian.
This might be dumb question but what is "PNP switch: ON" ?
The scheme is exactly the one i followed. I did it couple of times and never managed to get the MIL to start blinking...
It also mentioned:
============================================================
11. If idle speed and ignition timing are not within the specification,
“Idle Air Volume Learning” will not be carried out successfully."
============================================================
My idle speed is about 950RPM...so this by itself is out of spec, and maybe prevent me from successfully completing the air volume relearn process...
However, it doesn't make sense, as this whole relearn process suppose to fix the idle speed....
The thing thing i was thinking about is the position of the throttle when the engine is off. When i installed the new part, it looked like the "Door" was not 100% closed, and i believe the old TB part "Door" looked like "more closed" position, if you know what i mean.
Can i or should i physically attempt to push it in the direction of "closing" it further? Or will that damage it?
On top of the TB, there is a small screw that looks like a tune screw. Does that screw can "fine tune" the position of the "door" ?

[Towncivilian]

Park/neutral position switch - basically ensure you're in Park.

I have no experience with the electronic throttle/drive-by-wire systems of the 2003-2004 R50s. I don't think you should touch the "idle screw" though. I can see why you went with an aftermarket TB - a new OEM one is $520.99! Ouch.

I'm unsure of how to proceed regarding the relearn procedures, I've never had to perform any of them either, and the process is probably different for my 2001.5 anyway.

Have you ensured that your air intake assembly has no leaks?

[chicoson]

do not touch the idle screw! i messed with mine and it instantly threw a code. if you do it will know lol.

[Laker4ever]

I don't think that i have leaks. I torqued the TB with new gasket.
The TB that i got is i think the OEM. As it say HITACHI on it and the place where NISSAN was engraved was shaved off. I think because of the trade name. Cost me about $160.
Ok so i will not touch the screw...
I'm still curious to know why i couldn't get the MIL light to blink at the relearn sequence.

[ARKQX33V6]

If all is set, and that's a big if...check the coolant temperature switch sensor, a cold engine whether cold or a bad sensor will create a high idle to help speed up the warming cycle.


You may have to read the book to find the resistive values at different ambients and coolant temperatures to verify that sensor.

When the heat gauge is about at normal, at that time the engine shifts down to 750 RPM, watch your temp and see if any engine RPM even indicates a change.

[Laker4ever]

Update,
I had to do some other unrelated work on the Pathy, so i had to disconnect the battery for probably 4-5 hours...
So after i was done, I reconnected the battery and to my surprise, the RPM got back to the 750 RPM it was before...
Obviously the MIL light also is gone (previously it was on because of the High Idle RPM "P0507")
thank you everybody and hopefully this info will help others too.

[calwell]

I have a 2002 QX4. The idle speed fluctuates and the engine idles at 1300 rpm. Before I replaced the throttle body, the engine speed would fluctuate from 1000 rpm to 2000 rpm, after replacing the body it fluctuates 150 rpm, but still idles at 1300 rpm. Does anyone have an idea about the diagnosis and repair?

[Laker4ever]

make sure you don't have vacuum leaks. 1300 is way too high.
It is rarely that one has two problems, so if you replaced the TB with a brand new one and problem didn't get solved...maybe the TB was not the problem.
Also, you can follow my advice and disconnect the battery for about a full 24 hours...that would clear the ECM.
You can also attempt to do the calibrations discussed, but I had less success in that.

[i3igmind]

I don't think that i have leaks. I torqued the TB with new gasket.
The TB that i got is i think the OEM. As it say HITACHI on it and the place where NISSAN was engraved was shaved off. I think because of the trade name. Cost me about $160.
Ok so i will not touch the screw...
I'm still curious to know why i couldn't get the MIL light to blink at the relearn sequence.

where did you buy your TB from, i am having a hard time to locate one for my 97 QX4.

thank you in advance

[i3igmind]

Try following the three relearn procedures found on page EC-81.

hello ,
what will be the relearn procedures for a 97 infinity QX4 please

[Laker4ever]

I bought it at Oreilly's. Came to one of their stores, paid, the ordered it from their distribution or another location, called me within 3 hours to pick up.
Their price was the best considering no core charge.

[i3igmind]

if you don't mind posting the part no. i can not find it in their website. thank you

[Laker4ever]

I'm not sure if your 97 is the same as my 03 part.
I think you have VG33E engine while mine is the VQ35.
When i think about it....isn't your just mechanical TB that has a mechanical cable that it opening the flap door.
On the VQ engines it is electronic....

[i3igmind]

I'm not sure if your 97 is the same as my 03 part.
I think you have VG33E engine while mine is the VQ35.
When i think about it....isn't your just mechanical TB that has a mechanical cable that it opening the flap door.
On the VQ engines it is electronic....

yes mine is mechanical , i can't find a good picture of the element kit thermo and how the cam fast idle lay on top of that. the mechanic guy say its messed up and thats why i am having high idle @~1100 rpm . in my post am not getting any response so i start looking around , trying to get this baby running.

P.s: i was able to locate a TB for $40 i will go pick it up after work, any special instruction on how to change/replace it.

thank you in advance

[Laker4ever]

I'm not sure if your 97 is the same as my 03 part.
I think you have VG33E engine while mine is the VQ35.
When i think about it....isn't your just mechanical TB that has a mechanical cable that it opening the flap door.
On the VQ engines it is electronic....

yes mine is mechanical , i can't find a good picture of the element kit thermo and how the cam fast idle lay on top of that. the mechanic guy say its messed up and thats why i am having high idle @~1100 rpm . in my post am not getting any response so i start looking around , trying to get this baby running.

P.s: i was able to locate a TB for $40 i will go pick it up after work, any special instruction on how to change/replace it.

thank you in advance

I'm not sure.
I know it would be wise to use a new gasket, and make sure there are no vacuum leaks.

[Towncivilian]

On the VQ engines it is electronic....

2001-2002 Pathfinders have mechanical throttle bodies, 2003-2004 have electrical.

There are no idle relearn procedures for a 97 QX4, but there is a fast idle cam inspection and adjustment procedure. See EC-27.

[i3igmind]

Well i replaced my TB, which came with a TPS (so i hooked it as is , after i cleaned it with TB crc) , i have also replaced my fan coupling because it was not spinning causing high fan sound ( i found out that there were two screw out of four that are damaged , split in halfs, so now there is only two screws attaching the fan coupling to the water pump pulley). so my RPM drpped but not by much am at ~900 RPM.

Two questions:

Can i drive the car with the fan coupling delima , are there any danger i should be aware that might be caaused

What else should i look /replace to get my idle to the normal RPM which is ~750 rpm please

thank you

[Towncivilian]

I would not run the engine with the cooling fan not bolted in properly. An improperly installed fan can cause it to wobble and possibly separate from the fan coupling and cause quite a bit of damage.

If you haven't yet, try following the fast idle cam inspection and adjustment procedure I mentioned in my previous reply.