To start out, I have a IX and these are my mods: Intake, tbe, fuel pump, O2 housing, boost controller, 93 octane flash. The problem is that my car will not idle at a constant rpm like it should. When it is cold and warming up, it idles fine. When it is warm it does not. It idles around 950 rpm for a few moments and then the car sputters a little and almost stalls. The rpm drops and you will see in the video that the car goes real rich and then it returns to normal only to do this again and again. It has kind of always done this since I began modding it, but it is getting a lot worse now. I am buying some new spark plugs to see if that helps any even though the car runs really strong. This idle problem is really bugging me bad. Any ideas?

Video: http://media.putfile.com/Idle-troubles

edit: that is my gauges making noise in the background.

 

Take that intake off and all your troubles will be fixed!

 

and i didnt even watch the video

 

Have you checked for boost leaks?

 

Yes, w/ the home made tester, my car held 30 psi solid (I didn't test any higher than that).

 

That'd be the first thing I'd check; unmetered air is probably making its way past the MAF.

 

what intake do you have?

 

The intake I have is the HKS RS. I am positive there aren't any leaks. I've double checked everything and the boost leak test was good. I am beginning to wonder if something is wrong mechanically. I was looking at the map I was tuned w/ and my original map before any tuning and the idle settings were never changed. It should idle just like stock. MAF sensor going bad possibly? Maybe my knock sensor acting up? I have no clue.

 

Do you get frequent SES? Has the car been on a scan tool to check for DTC's? What other mods are on the car?

 

What is SES? The only other mod I have that I forgot to mention is a fmic. I have not checked for any DTC's. There is not a CEL, but I could check tosee if there are any "ghost" codes.

 

I had this problem on the dyno over the weekend with my new IX after installing a bleeder tube and then switching to an MBC. It was pissing me off.

Turns out the plug to the MAF on my IX didn't make as positive "click" as my VIII, and it wasn't "clicked home" so to speak. I uninstalled and reisntalled the maf pipe, maf, and airbox, then cleared the ECU and it went away.

Disconnect your negative terminal battery for a few seconds, leave a dome light on to sap all the power. Disconnect the MAF clip to the MAF and make sure there is no dust/obstruction on either side of the electrical connection. Reattach MAF clip to MAF then battery terminal. Start car and tell me if it goes away.

 

bet u any amount of money its the intake lol. my car idles just like that when its cold out. it doesn't bother me tho lol

 

*Update*
I recently installed ARP head studs and put the car completely back to stock except for a cat-back. All vacuum lines are secure, no boost leaks, etc. This means stock intake again. Well, there is no change at all. My IX MR still does this weird stumbling idle. I even changed the map in ECUflash back to stock and it didn't make a difference. I am at a loss at this point. I have got to figure this out, no one seems to know why it does this.

 

Check your coolant temperature sending unit if it is getting erratic readings it could do this as well. The gauge itself may not move fast enough to see blips in the readings if there is a minor short in the circuit.

Good luck

 

HAve you checked or tried swapping out your coil packs?