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Need help. Power loss.

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Old 08-17-2010 | 06:11 PM
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Ok so I just finished doing those resets. Doesn't appear to be any change. Oh and apparently the p0300 code for multiple random cylinder misfire came back
Old 08-17-2010 | 06:25 PM
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Are the coils mounted properly? No damage to any of them? I can't think of anything else. Have the coils checked to see if they're working properly.
Old 08-17-2010 | 06:33 PM
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Originally Posted by dmroberson
Ok so I just finished doing those resets. Doesn't appear to be any change. Oh and apparently the p0300 code for multiple random cylinder misfire came back
is your car idle right at 1 rpm?

when you cleaned your throttle body, did you remember to disconnect the battery first? And did you manually open the throttlebody butterfly to clean the inside? if so, then that code is most likely that and you messed up your throttle body.
Old 08-17-2010 | 06:54 PM
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Originally Posted by Q8y_drifter
Are the coils mounted properly? No damage to any of them? I can't think of anything else. Have the coils checked to see if they're working properly.
As far as I can tell there is no physical damage or anything. They appear to be seated firmly
Old 08-17-2010 | 06:58 PM
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Originally Posted by SuperBlack350z
is your car idle right at 1 rpm?

when you cleaned your throttle body, did you remember to disconnect the battery first? And did you manually open the throttlebody butterfly to clean the inside? if so, then that code is most likely that and you messed up your throttle body.
The idle is where it has always been, between about 750 and 1000 when warm.

Yes. I unplugged the battery, as well as the connector to the throttle body, itself. And yes. I poked it open with my finger.

I read that the throttle body has to be reset if you open it manually but I didn't try that yet. Looking for the steps in the service manual
Old 08-17-2010 | 07:17 PM
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Originally Posted by dmroberson
The idle is where it has always been, between about 750 and 1000 when warm.

Yes. I unplugged the battery, as well as the connector to the throttle body, itself. And yes. I poked it open with my finger.

I read that the throttle body has to be reset if you open it manually but I didn't try that yet. Looking for the steps in the service manual
Accelerator Pedal Released Position Learning
DESCRIPTION
Accelerator Pedal Released Position Learning is an operation to learn the fully released position of the accelerator pedal by monitoring the accelerator pedal position sensor output signal. It must be performed each time harness connector of accelerator pedal position sensor or ECM is disconnected.

OPERATION PROCEDURE
1. Make sure that accelerator pedal is fully released.
2. Turn ignition switch ON and wait at least 2 seconds.
3. Turn ignition switch OFF and wait at least 10 seconds.
4. Turn ignition switch ON and wait at least 2 seconds.
5. Turn ignition switch OFF and wait at least 10 seconds.

Throttle Valve Closed Position Learning
DESCRIPTION
Throttle Valve Closed Position Learning is an operation to learn the fully closed position of the throttle valve by monitoring the throttle position sensor output signal. It must be performed each time harness connector of electric throttle control actuator or ECM is disconnected.

OPERATION PROCEDURE
1. Make sure that accelerator pedal is fully released.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
Make sure that throttle valve moves during above 10 seconds by confirming the operating sound.


Idle Air Volume Learning
DESCRIPTION
Idle Air Volume Learning is an operation to learn the idle air volume that keeps each engine within the specific range. It must be performed under any of the following conditions:
 Each time electric throttle control actuator or ECM is replaced.
 Idle speed or ignition timing is out of specification.
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: 70 - 100°C (158 - 212°F)
 Park/neutral position (PNP) switch: ON
 Electric 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
For A/T models with CONSULT-II, drive vehicle until “ATF TEMP SE 1” in “DATA MONITOR” mode of “A/T” system indicates less than 0.9V.
For A/T models without CONSULT-II and M/T models, drive vehicle for 10 minutes.


OPERATION PROCEDURE

With CONSULT-II
1. Perform EC-42, "Accelerator Pedal Released Position Learning" .
2. Perform EC-42, "Throttle Valve Closed Position Learning" .
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. Select “IDLE AIR VOL LEARN” in “WORK SUPPORT” mode.
6. Touch “START” and wait 20 seconds.
7. Make sure that “CMPLT” is displayed on CONSULT-II screen. If
“CMPLT” is not displayed, Idle Air Volume Learning will not be
carried out successfully. In this case, find the cause of the incident
by referring to the DIAGNOSIS PROCEDURE below.
8. Rev up the engine two or three times and make sure that idle
speed and ignition timing are within the specifications.

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 EC-42, "Accelerator Pedal Released Position Learning" .
2. Perform EC-42, "Throttle Valve Closed Position Learning" .
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 switch 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 keep it for approx. 20 seconds until the MIL stops blinking and turned ON.
9. Fully release the accelerator pedal within 3 seconds after the MIL turned ON.
10. Start engine and let it idle.
11. Wait 20 seconds.
12. Rev up the engine two or three times and make sure that idle speed and ignition timing are within the specifications.
13. If idle speed and ignition timing are not within the specification, Idle Air Volume Learning will not be carried out successfully. In this case, find the cause of the incident by referring to the DIAGNOSTIC PROCEDURE below.
Old 08-17-2010 | 07:23 PM
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I did all 3 of those, as well as the Exhaust Valve Timing Control Learning, since I have a Revup. Nothing changed after doing any of that.
Old 08-17-2010 | 07:30 PM
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did the check engine turn off then turned back on?
Old 08-17-2010 | 07:33 PM
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was flashing as expected, during the relearns, but it hasn't come back yet.
Old 08-18-2010 | 01:00 AM
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OK, so the plan this weekend, will be to tear it down again. At that time, I'll look at the coils again, and make sure they're ok. Once that's done, I'll start to rebuild, and make sure that everything is tightened down completely. And we'll see what happens from there.
Old 08-18-2010 | 08:02 AM
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I suggest concentrating on the MAF. I really think that is your culprit.
But it doesn't hurt to doublecheck the coils are securely connected.
Old 08-18-2010 | 08:36 PM
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Originally Posted by Zazz93
I suggest concentrating on the MAF. I really think that is your culprit.
But it doesn't hurt to doublecheck the coils are securely connected.
I just ordered another MAF for $85, so I'll give that a try when it gets here... but in the meantime, I'll check everything else out.
Old 08-21-2010 | 01:00 AM
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Update:

Ok, so we took the engine all the way down again. Double-checked all of the gaskets, even added silicone to make sure we had a good seal. Swapped in the new spark plugs, since we know they're not bad, and also looked at the ignition coils. Everything went back together smoothly. Fired the engine up. Sounded much better. The engine sounds much more throaty now that the MREV2 is in.

However, there is no change. Still getting the CEL. This time, it was flashing first, then it remained illuminated...

It's really annoying me. I don't understand what could have possibly gone wrong with this thing...
Old 08-21-2010 | 02:05 AM
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One area to look if all else fails.
I have heard of this in later models VQ when a sensor fails.

NTB03-124 December 19, 2003
VOLUNTARY RECALL CAMPAIGN
ENGINE SENSORS

INTRODUCTION
Nissan has determined that some 2000-2003 model year Nissan vehicles may have a
defect which relates to motor vehicle safety. The engine might stop running while being
driven if the crank position sensor or cam position sensor fails. This may also result in the
“Service Engine Soon” light coming on or reduced engine power. If the engine stops
running while driving, this could result in a crash without warning.
Old 08-21-2010 | 04:08 AM
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If your light is 'flashing' that means something is very wrong with the ignition system.. Either you still have some coils / injectors wiired wrong or a bad coil pack. You should be able to hear the misfire pretty clearly by the time the light flashes meaning 'gross misfire'.
Old 08-21-2010 | 06:51 AM
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I think it was said before but I know the #4 and #6 leads are easily misconnected to each other. I did that and destroyed a cat. Double-check those leads and make sure they are connected to the right places. I'd show you a picture of how if should look but my car is still in pieces from the engine rebuild. I would say to flip them and start it up, if it doesn't sound immediately better and more repsonsive cut it and put it back before getting too much fuel to the cats.
Old 08-21-2010 | 10:34 AM
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Just to add to this, I have the exact same problem. It started out that I'd misfire very rarely, but now I'll misfire and cant drive the car. I thought I had a vacuum leak but couldnt find anything. Bought a brand new TB and replaced the plugs. I cant get the car to tell me which cyl is misfiring because theres an overriding P0102 code that I cannot get to go away and cant find a simple explanation for. I'm lost and fed up
Old 08-21-2010 | 02:06 PM
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Another...
I saw this on another forum once...forgot where..

The 05 had an issue with the fly wheel, and needed to redesign it as when it got hot, it expanded and rubbed against the sensor, so they replaced the sensor again, and replaced the fly wheel
Old 08-21-2010 | 02:18 PM
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this is after we put it back together. Hope this helps
Old 08-21-2010 | 05:53 PM
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Originally Posted by Zazz93
I think it was said before but I know the #4 and #6 leads are easily misconnected to each other. I did that and destroyed a cat. Double-check those leads and make sure they are connected to the right places. I'd show you a picture of how if should look but my car is still in pieces from the engine rebuild. I would say to flip them and start it up, if it doesn't sound immediately better and more repsonsive cut it and put it back before getting too much fuel to the cats.
I did make the mistake of connecting #4 and #6 backwards, but I found that and fixed that early on. Everything is connected in the proper order.


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