Here's the deal: I installed the Stillen Air Box, it caused my coupes idle to run weird, sometimes dying after high revs. I took it off and replace the stock air box. All problems where gone. Yesterday I put the Injen Cold Air Intake, and the crawford plenum, and my CAR RUNS GREAT, except, I am having the idle issue again. The car idles at 600 rpms, it should idle from 700-900 rpms. It also tries to die or drop below 500 rpms after high revs. Sometimes it bounces back up to 600-1100, or goes all the way to 0. Any opinions? Car techs, does anyone have a clue what is causing intakes that no one else has a problem with, to mess my idle up so bad?

 

Had the same problem with my JWT pop charger. I now have the Injen intake and no problems. Just let you ECU adapt to the new mods. It took my car a couple of weeks to adjust. I was stalling every time I was at high revs and let the rpms drop on their own. It went away after a while and have not had a stall in 15,000 miles.

 

I had a rough idle with my injen too. Take the negative batery terminal off overnight. That helped mine out.

 

Negative Battery Terminal.... what did that do? That's a new one. What a cool little trick.

 

Some cars stall under these conditions with the stock air inlet system.

I highly recommend you try the following procedures. This is what your dealer would do to start with.


Accelerator Pedal Release Position Learning Procedure.

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


Throttle Valve Closed Position Learning

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


Idle Air Volume Learning (Throttle Position Learning)
It is better to count the time accurately with a clock.

1. Perform “Accelerator Pedal Released Position Learning”.
2. Perform “Throttle Valve Closed Position Learning”.
3. Start engine and warm it up to normal operating temperature.
4. Turn ignition switch “OFF” and wait at least 10 seconds.
5. Conform that accelerator pedal is fully released, turn ignition switch “ON” and wait 3 seconds.
6. Repeat the following (steps 7a, 7b) procedures quickly five times within 5 seconds.
7a. Fully depress the accelerator pedal (HARD)
7b. Fully release the accelerator pedal.
8. Wait 7 seconds, fully depress the accelerator pedal and keep it for approx. 20 seconds until the Check Engine Light (CEL) stops blinking and turned ON.
9. Fully release the accelerator pedal within 3 seconds after the CEL is ON.
10. Start engine and let it idle.
11. Wait 20 seconds.
12. Rev up the engine two or three times and make sure the idle speed and ignition timing are within the specifications.


DaveO

 

by removing power to the car for an amount of time, will reset your ECU and should adapt to the new mod

 

Be carefull of excessive oil on the filter element. even pre-oiled filters may allow a slight film to build up in the MAS and cause a slow response in fuel enrichment, rough idle and stalling.

 

I have heard about the oil on the MAS. Is there a proper way to clean it without harming it?

 

I thought that does not work on the Z and you have to go through the reset process.

 

I use a NON-RESIDUAL Contact cleaner after removing the MAS from the car. Carb or Brake cleaner can leave a film on the sensor that can bake on and damage the sensor.

 

taking the negative battery terminal off does infact work. I had a check engine light and I disconnected the negative terminal and let it sit over night. when I started it up no check engine light. so it resets the ecu.

 

OK, I've got some questions regarding this that hopefully someone can help with. I'm a bit concerned now, as I run the Stillen intake which puts a very large oiled conical K&N filter directly in front of the MAS. I've cleaned and re-oiled it once using K&N cleaner and oil and following the directions closely. I made sure to wipe off any excess oil from the filter areas and even blot the surfaces of the filter lightly to take up any excess oil. I haven't had any problems, but I'm a little worried.

1. Can you give an example of a good non-residual contact cleaner?
2. Would denatured alcohol work?
3. Is it a good idea to periodically clean your MAS in this way if running an aftermarket oiled filter?
4. Will cleaning it over time damage the MAS?
5. How much is it to replace if you f@&! it up?

 

1. Brody and CRC make good cleaners that are quick drying and non-residual. There are more out there.
2. If the denatured alcohol doesn't state that it is a non-residual cleaner for electrical components I woundn't use it. Besides, doesn't denatured alcohol melt some plastics?
3. If you use only a small amount of oil on the filter it shouldn't be necessary.
4. It is possible. However if you notice a repeated problem with this after cleaning and oiling your filter, you should reduce the amount of oil you are using on the filter.
5. TOO MUCH!!!