Hi ,
recently I encountered this problem - when I start the engine in the morning, Idle is fine even when the engine gets warm.

But when I stop at lights after a longer and a litte bit aggresive driving, my idle jumps from about 300 to 1000 rpm, and sometimes it even drops to 0 and engine stops. My idle is set to 800 rpm in ECU.

Any idea?

 

possible vac leak? Thats where I would start. Not sure what your running (stock?). More info would be great. Have you done any work on your car as of late (recently)?

 

I was thinking about tha vacuum leak as well, I checked the lines that can be seen well from the top of engine, maybe I will have to do a better check.

Why does it run wel after starting the engine in the morning? Am I right thinking leak would cause problems all the time?

 

Have you looked at this?

https://www.evolutionm.net/forums/ev...s-do-asap.html

 

Thanks, I will check as soon as I get from work.
Martin.

 

np

Are you anywhere near or in Moravia?

 

Yes I am in Moravia near Ostrava

I checked the lineas and seem OK, the idle stopped hesitating after I disconnected MAF sensor, could it be malfunctional? The car only has problems with idle...

 

one more try - I have cleaned MAF and air filter, as they dry I will try if it gets better

 

didn´t help :-(

 

There was a TSB flash for US based cars to fix the idling issue. Was that available to you in the Czech republic?

 

Is your car stock? If so, the erratic idle was a common issue and was addressed by a dealership flash of the ECU (as mentioned by the guy above me). Not sure what was available to you since you're not in the USA.

If you're not stock, you should discuss with your tuner and whomever installed your mods. It could be a number of different things.

 

Unfortunatelly not...

 

My car is stage 2 with drop-in, but I had no issues with it in the past.

 

WTF - today I got CELs:

1) cylinder 2 misfire
2) O2 sensor #1 no activity

After clearing them they did not come again - could the problem be O2 giving wrong signal?

Why does it work fine (stable idle 1000rpm) when I disconnect MAF?

 

Because there is limp home feature, kind of safety net, when some of the sensors goes nuts, that you can drive to the dealer