[sentraracer487]

I have a 2004 sentra spec-v and i need help. i recently got a check engine light and idle issues after cleaning the throttle body with ams oil power foam throttle body cleaner. the dealership tells me that the computer lost memory of the correct idle and that i need to have them reset the computer. but i dont want to pay them to do it because ive worked on cars for the past 5 years however i never messed much with ecu's. i would like to know how i could reset the ecu on my car or how to fix this problem or if anyone else has had similar issues.

thank you
sentraracer487

 

[saint0421]

first off, our TBs are uber sensitive. Spraying TB cleaner directly into the TB most times causes them to go hay wire.

You can do the idle air volume relearn to steady your idle: http://myspecv.com/f/t160671.html

Resetting the SES light: ECU code listing and how to (SES light) - MSV

 

[metro273]

^^^Not only that but forcing the throttle plate open with your fingers could damage the throttle chamber entirely. This has happened numerous times at our dealership! Hopefully he needs to just relearn the idle...

 

[sentraracer487]

Thanks Saint all i had to do was reset the ecu and the problem cleared right up, and to metro i made sure not to force the plate open i just sprayed a little bit at a time while idling. thanks guys

 

[sentraracer487]

ok so resetting the computer only worked for a little while, i got info on how to relern idle somewhere else because your link didnt work saint. how can i fix this the idle has gotten worse, coming up to a stop it fluctuates between 1000 and 2000 rpm back and fourth unless i sit for a minute. the dealership said that they might have to replace the throttle body, should i order one? one more question i still have a factory powertrain warranty, however they say the throttle body isnt covered wtf?

 

[saint0421]

Taken from another forum:

This is referenced straight from the Nissan Service Manual

From a 2004 Spec V, but the same for all Nissan's with electronic TB and accelerator pedal.

I hope this is beneficial to all who use it. Note: Timing in this procedure is critical in order for it to be successful.


PREPARATION
Before performing Idle Air Volume Learning, make sure that all of the following conditions are satisfied. Learning will be cancelled if any of the following conditions are missed for even a moment.
● Battery Voltage: More than 12.9V (At idle)
● Engine coolant temperature : 158-203°F
● For A/T vehicles: PNP (Park/Neutral Position) switch: ON
M/T vehicles: Neutral switch: ON
● Electrical load switch: OFF
(Air conditioner, headlamp, rear window defogger)
On vehicles equipped with daytime light systems, if the parking brake is applied
before the engine is started, the headlamp will not be illuminated.
● Steering wheel: Neutral (straight-ahead position)
● Vehicle speed: Stopped
● Transmission: Warmed-up (Drive vehicle for 10 minutes)


OPERATION PROCEDURE
Without Consult-II
NOTE: ● It is better to count the time accurately with a clock.
● It is impossible to switch the diagnostic mode when an accelerator pedal position
sensor circuit has a malfunction.

1. Perform "Accelerator Pedal Released Position Learning"
a) Make sure accelerator pedal is fully released.
b) Turn ignition ON and wait at least 2 seconds.
c) Turn ignition OFF and wait at least 10 seconds.
d) Turn ignition ON and wait at least 2 seconds.
e) Turn ignition OFF and wait at least 10 seconds.

2. Perform "Throttle Valve Closed Position Learning"
a) Make sure accelerator pedal is fully released.
b) Turn ignition ON.
c) Turn ignition OFF wait at least 10 seconds.
Make sure that throttle valve moves during above 10 seconds by confirming
the operation sound.

3. Start engine and warm it up to normal operating temperature.

4. Check that all items listed under the topic "PREPARATION" (previously mentioned) are in
good order.

5. Turn ignition OFF and wait at least 10 seconds.

6. Confirm that accelerator pedal is fully released, turn ignition switch ON and wait 3
seconds.

7. Repeat the following procedure quickly five times within 5 seconds.
a) Fully depress the accelerator pedal.
b) Fully release the accelerator pedal.

8. Wait 7 seconds, fully depress the accelerator pedal and hold for approx. 20 seconds untill
MIL (Malfunction Indicator Lamp, a.k.a. SES light) stops blinking and is turned ON.

9. Fully release the accelerator pedal within 3 seconds after MIL (SES) turned ON.

10. Start engine and let it idle.

11. Wait 20 seconds.


Procedure timing chart
IAVL pic.bmp


12. Rev up the engine two or three times and make sure that idle speed and ignition timing
are within the specifications.

 

[sentraracer487]

thanks for getting back to me so quick saint, ill try this and get back to you if it worked. but if it doesnt work do i have to replace the tb or is there any other options for me? and also i apologize about seeming stupid on this but this is my first car with electronic throttle and ive worked in a garage that isnt nissan specific so i only know generalizations.

 

[saint0421]

If the idle doesnt stick then it would very likely point to the TB since you had already sprayed the TB cleaner. For our electronic TB, it's much safer on the TB to spray cleaner on a rag to wipe away the gunk build up instead of spraying directly on the TB.

 

[sentraracer487]

ok well its better today but not by much, the idle is still going between 1000 and 1500 rpms. do you possibly know of a company selling either oem tb's or maybe even an upgraded tb ported or larger? im hoping to start work on this engine and possibly start taking it to the track with my friend any suggestions will be greatly appreciated.

 

[saint0421]

Larger/upgraded TB are gunna have to be a custom job. Yay for electronic TBs (sarcasm). IIRC altima QR TBs ought to fit as well. Dont know of a specific company selling OEMs besides the usual autoparts stores/dealers.

 

[sentraracer487]

is there anything else i can do to fix this before i go out and buy a tb. i really am tight on money, yay college.

 

[saint0421]

is there anything else i can do to fix this before i go out and buy a tb. i really am tight on money, yay college.

A vacuum leak would cause an idle issue as well.

 

[sentraracer487]

would that cause such a great fluctuation in the idle?

 

[sentraracer487]

A vacuum leak would cause an idle issue as well.

But would a vacuum leak cause a 700 rpm fluctuation?

 

[saint0421]

But would a vacuum leak cause a 700 rpm fluctuation?

Yes, it could