Just had my spark plugs changed with NKG laser platinum plugs and as I reassembled and started the car I noticed the RPM became notchy. On the start the RPM bleep has pauses in its movement instead of smoothly going up and down. The same is when you press gas, its not a smooth delivery. There are hesitations and then rapid increase in power delivery when you're accelerating. So strange, I changed the air intake manifold gasket when doing plugs and checked for any air leaks or loose vacuum lines; nothing. Its not throwing any codes, idles smooth, drives overall fine but with this shaky RPM, the car reacts accordingly, eats gas noticeably more as well =[

Here's a warm start vid and idle. At cold start its more noticeable and during first to second gear changes.Ill try to get more videos today. Not sure how to go about fixing it, please help.
Thank you guys!

 

I guess you hook it up on the OBD scan tool. Did you clean the throttle or move the butterfly? Check all the connector that you previously unplug. Clean the maf sensor. You need to reset the ecu by doing the idle relearn procedure.

 

Thank you colt.
I did see some black buildup on the butterfly. Kind of scared to clean the maf sensor, people here have mentioned how it starts acting up after cleaning.

To reset the ecu, do I follow this instruction?
http://forums.maxima.org/5th-generat...u-02-03-a.html

And Idle relearn by following this?
http://nissanhelp.com/diy/altima/pro..._procudure.php

 

Just clean the outside area of the throttle with a rag mildly soaked with throttle cleaner . Do not touch the butterfly.
Read this: page 2 relearn procedure
http://www.nwpengineering.com/NWP%20...0Bore%20TB.pdf

Read this:http://www.nicoclub.com/FSM/Maxima/2002/

After deleting any error code, if the OBD Scan tool have a live feed, it will give you a pending code without SES to reset this you need to do the drive cycle.
Read this
http://repairpal.com/how-to-perform-a-basic-drive-cycle

 

Thanks a lot colt, will get right on it!

 

After cleaning my TB, I did the relearn procedures a few times before the idle stabilized. Once I finally got it, the next day it was a bit screwy again.

I finally did the relearn a few more times until it was just right, then I put the headlights to the parking setting, turned everything off, disconnected the battery and left it for 24 hours.

Once I connected the battery again and turned the car on, the idle was perfect and everything has been great since then. Since I did the relearn more than a few times and the inconsistent idle always came back... I have to assume that disconnecting my battery did the trick. I have read some threads that say it only requires about 15 minutes, but I wanted to make sure the relearns stuck in the ECU.

 

Disconnecting will not do anything on 5th generation maxima, it might work on the 4th gen. Ideally you need a stopwatch to do the right timing of sequence of relearn. I guess you got it right.

 

Did you check the gap on each yourself and torque the plugs to spec? Gap is 0.043 (3.0) or 0.044 (3.5) and torque spec is 14-22 ft/lbs. If the issue wasn't there before the plug change, chances are one of these is your issue. Or, a loose connection to a coil pack.

 

Sorry, I believed the spark plug torque range for VQ35DE is 13-15 ft-lb.

 

Have you checked for a vacuum leak around intake manifold? Mine did the same thing after I changed my plugs and I hadnt tightened a bolt completely and there was a slight opening where the intake lead into the runners of the manifold.

To check for a vacuum leak, start the car, let it warm up and come to an idle, then spray brake cleaner where the pieces of the intake mani meet/bolt together. If there is a leak, the brake cleaner will be sucked in and bog the engine.

 

Both are the same procedure...

 

if you ever figure this out please reply back... i have the exact same issue rpms stick when going up and down. i figured its a **** tach or the connection.

 

Thanks a lot for your responses guys. I haven't had a chance to look into it yet. Car has been sitting. I did check for vacuum leaks around the intake manifold, nothing.

Going to try the relearn and if not will have go in and check torque.

 

Did the ecu reset a few times, nothings changed. Going to check each plug next =/

 

Use dielectric grease inside each coilpack boot....inspect your coilpack boots for rips, holes or tears!