I just installed injen intake~!!
I am really satisfied with injen~!!
But I got some problem with it. I am not sure everyone is having this kind of problem or not..
After i installed injen, it was ok but after 2~3min later, the RPM went down and the engine was almost tune off.
It works really fine while i am driving but when i park and leave it for while, RPM drops down to 4~4.5. ( It used to be at above 6)
Plz let me know if there is something that i am missing..
Thank you everyone......

 

By 4.5, I assume you mean 450 and not 4500?

Mine used to idle at about 750 but now with the grounding kit and my AEM intake, it sits at about 5-600 and is very smooth.

Not sure why it drops off on you. Anyone else with an Ingen have this problem?

 

I have a new exhaust and injen CIA on my Z it also is having this same problem. It seems from the other forums I have read that the newer injen intakes with the small filter that connects to the smaller hose that branches off from the main intake pipe might be the cause??????

 

I have INJEN CAI, Fujitsubo exhaust and no problems whatsoever, the car idles smooooth.

You might want to check the orientation of the air flow sensor, for some reason INJEN was specific that the connector be on top.

You might want to try a grounding kit as well, I had one on before the CAI so I don't know if it will have an effect for you.

 

Yes! I have the same problem too! only mine is around 600 and when idle there are some sudden drops in rpm really close to 500. my sensor connector is placed on top. installed the HKS circle earth grounding kit after and it's much smoother now but the rpm is still very low at idle.

 

hahahha Sunghoon....wassup man...I just came back to Korea and looked at your thread. Well, I got grounding kit and Injen CAI too, (Short Ram version for now tho) and experiencing same low idle rpm, but not that bad. Well, dunno maybe you f**ed something up while you are installing it
Anyway good luck and see ya later this summer.

 

adjust your throttle position

 

Haven't had a single problem like that, and I've had my InJen installed for a while now. Did you disconnect the battery while you installed it?

 

~!!
i forgot to disconnect the battery while i am installing..~~!!!!!!
do you think that why i am having this problem??
what should i do then?

 

Us G35 owners has a similar problem with our Injens. When we are going 75+mph, and hold down the clutch so the car is coasting. THe engine will just stall out. I have contacted Injen about this, and they said it was because of the sensitive MAF. Do the test, see if you car does this too. Drive 80mph on a straight empty highway, then just shift in nuetral, and let the RPM's slowly drop down to idle. 3/5th of the time, the engine will just shut off. Injen is currently redesigning the intakes for the G because this minor flaw might be very dangerous for the unexperienced driver.

 

Just wondering if anyone had a fix for the rough idle problem? I think the car drives better with the CAI, i can feel more power and it drives smoother, easier to drive, maybe because i reset the ECU when i put the CAI in, but the idle still sucks. Sometimes it sticks at 750, but then it drops down to 500-600 and feels a little rough, but so far mine hasn't stalled.

 

I thought it was a little rough when i first put it in, but after a day, it stabilized back to about 750rpm.

 

Maybe. Try disconnecting the negative battery terminal for about an hour when you get home one night. The InJen instructions say to do this to allow the ECU to readjust. If it doesn't get better after that, you might want to call them and see if they have any suggestions. Good luck!

 

Did you try resetting the idle learning as per the service manual? dwnshift posted the directions towards the end of this thread:

https://my350z.com/forum/showthread....threadid=26115

 

I have had mine for a while as well, I haven't had any problems thus far.

 

Oh! disconnect for an hour?! i guess i will try that. i only disconnected the battery for about 5 min after the intake installation and then went out for a spin... ok, an hour

also, can someone please post a pic of the stock intake especially where the sensor is located? thanks!

 

Having the same problem....

When I turn on the A/C compressor, though, the idle stabilizes quite nicely....

Going in for the window TSB tomorrow... dealer installed the Injen for me... I'll ask about the battery and take a peek at the position of the sensor.....

Cheers!

 

Your ECU or ECM (computer in your car) has not adjusted yet. give it time and it should correct itself. I had the same problem with short ram intake and it went away after a couple of weeks.

 

Hey although this is an old thread, I had a similar problem with the JWT popcharger. I realised I had made a stupid mistake which was causing the same problems you listed. When I bolted the MAF on the intake, I didn't keep the horizontal alignment of the MAF sensor, but bolted it on vertically. I immediately had problems with a rough idle. I then rebolted to horizontal, and voila, problem fixed.

I don't know if this could be the same problem you were experiencing, but maybe it might help others.




meta:
STALL IDLE ROUGH INTAKE

 

My Z idles at 600 in 59 degree weather. Im also highly modified with a apexi cold air intake, Injen exhaust, crawford headers, cats, plenum, unorthrodox racing pulley, HKS grounding kit, and im going to be installing JWT cams soon . So i called technosqaure they told me when i get my reflash done they can higher my idle for my cams and my mods i have now. Im going to have my idle set higher at 900 for my cams to run smooth with my mods. So if your worried about the idle i would call technosqaure, or have nissan higher you idle. It should not take them longer then 10 minutes to do.

Thanks Glen