Rough idling...

[JEZ 8553]

Not sure if this is normal but i recently changed to a FMIC and Forge re-circ, now when the engine is warm it idles at about 800 rpm but causes quite a bit more vibration through the car, almost as if its idling too low. Ive adjusted the idle speed screw by 1 turn which has helped but is this normal when changing to a FMIC or different BOV/Re-circ or have i now got a gasket blowing (doesnt sound abnormal when driving and no noticable loss of boost) ?

* - Btw its not a coil issue as i recently replaced 1 faulty coil so i know what its like running on 3 cylinders.

 

[DeanS15]

hey jez - glad you finally got it fitted:nod:
i didnt notice any difference in idle when the fmic was fitted, seemed to feel a little bit more eager but the amount of vibration did go up a little (by no means a lot though). i put this down to the fact that it is all hard pipes now so there is no longer much articulation between the engine and cooler, which is bolted to the chassis without any rubber bushes or shock absorbing washers like the original. guess any engine movement shows up through the cooler/chassis now. idle speed sounds good 800-850........

 

[JEZ 8553]

Yes mate, got it done weekend before last as i only got the FMIC a couple of weeks ago. Cheers for lending me the holesaw

To be honest its not bad, just the vibration felt worse, obviously if this is to be expected its all fine i guess. Setting the idle slightly higher helps reduce most of the vibration anyway.

 

[GUEST_JDM]

does the idle jump and go fall a little by any chance?

 

[JEZ 8553]

No not really, it idles fine, doesnt really hunt about at all just theres more vibration than before fitting the FMIC and Forge Re-Circ, i was wondering if anyone had noticed before incase its a very small hose/gasket leak. Im guessing what Dean said will probably be the case with all the piping being bolted to the engine and chassis is transferring more vibration than before.

 

[spoonman]

bringing up a old thread about a similar issue. since installing my new dump pipe a tomei 2 3/4" (was told it was a 3") my car has trouble maintaining idle speed once hot, at cold it will idle at 800 - 850 but once hot it struggles to maintain idle speed and keeps going up to 800 then droping to 500 back up to 800 drop to 500 and so on.
Still on the factory ECU, i have just had the turbo off to replace the oil/water lines with braided ones
Mod list so far is
FMIC, POD filter, heat7 pugs, dump pipe, stock front pipe(temporary for next week) 3"cat back, running on 96 Octane.

Could this just be the factory ECU does not know what to do with the funky exhaust going from 2 3/4" to 2" to 3" or is this something else.

heres a clip, the rattle is something sitting on the dash.

anyone know how to post embedded links?

<iframe width="425" height="349" src="http://www.youtube.com/embed/W8MOJZ45X34" frameborder="0" allowfullscreen></iframe>

 

[JapanS15]

have you checked for leaks in all your piping?

 

[spoonman]

year tight as, but i really want to try that trick where you remove the MAF and pressurize the intake to check for leaks