high idle - evo4

[Dnos]

hey, ive read other topics about this but they all were about after market problems while mine is stock.

Since ive had the car this idle has slowly been getting higher and higher. When i got it it was idling about 900 which was great for me.

Now after a 2 hour open road drive with a average speed of 140km/s i get to the town i was heading to pull up at lights and its now at 2.6rpm (before the drive was at 1.8rpm)

anyhelp would be great.

oh and just to make sure the idle control is the small screw under the throttle control under bonnet? very sorry dont know the name of it. If so which direction should i screw it to lower, as i havnt had luck either way

 

[HermaN]

When adjusting the idle screw you need to park the stepper motor, otherwise you will be fighting with the ECU as to what idle you want. To park the stepper you need EvoScan and an Open Port cable.

You can also reset it by removing the battery for 10 mins, plugging it back in, turning the car on, let it idle with everything turned off, then for another 10 mins with everything (wipers, lights, heaters, heated screens, cd player, etc) turned on.

However that will be more of a temp fix, you need to park the stepper, sort the base idle, then do the above 10 mins idle with everything off and again with everything on.

If they don't sort it, then sounds like a possible boost leak and when on idle the vacum created sucks in un-metered air that causes idle to go high.

 

[RsvRob]

As Above

 

[Dnos]

thanks for reply. Dont have evoscan. So i'll try the battery trick when i get to work. Temporary or not its gotta be better than it reving so high

 

[Dnos]

just got from work, the battery trick didnt work. when that failed i played with idle screw and got idle down to 1000rpm. Guess the ECU reset it? As when i left work it still high.

So got a serious problem? I've checked all the hoses that have to do with air. Well least i think i have, not that knowledgable in veichles

 

[HermaN]

When adjusting the screw you need to park the stepper with EvoScan or similar. Either buy the cable and software or take it to someone that has the cable and software, park the stepper then adjust the base idle.

Boost leak is also possible, pressurise the intake system up to 1.5 bar and listen for any leaks. Or take it to a company that can smoke test the intake pipework.