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Poor Idle with Power FC???

Steve

By Steve,
in Engines & Forced Induction

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Steve Grand Master

Steve

Posted
Posted

Has anyone else had troubles with the idle quality of their car after fitting power fc?

Since fitting mine, it has a tendancy to hunt. Mainly when coming back in revs, and it will settle down after a while - but initially it is pretty poor.

I dont believe it is the decelleration fuel cut recovery rpm setting, as I have tried different settings with no avail. The car will idle smoothly if left long enough at idle, so I dont think it is the AAC valve either?

Has anyone else has had this problem, and had any luck with fixing it?

Cheers

Steve

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JimX Grand Master

JimX

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I've got the same problem, although it is still better than the stock ECU. Sometimes it will die soon after starting, and I have to give the accelerator pedal a few pumps to get it to idle properly for maybe 10 seconds or so when cold. But it's not always like this when cold for some reason.

My idle setting doesn't seem to do anything either, the car seems to idle wherever it likes, and it changes every so often up or down. I might have a faulty idle control motor or something.

SeD Apprentice

SeD

Posted
Posted
Unrelated id say.

Shitty idle most likely due to 0/2 Feedback still being on, makes idle pretty crap turn that off and idle will be great.

<----------------- how is this done??? how can u turn it off. soz dont know much about this topic but im interested. and finally how much can a PFC get picked up for brand new/ second hand

cheers

Steve Grand Master

Steve

Posted
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Posted

If you turn off your 02 feedback, it could result in worse economy.

02 feedback is used for closed loop running, such as cruise or idle - it will try and get the mixtures as lean as possible - AFAIK

I tried switching off 02 feedback, and it made no difference. This is something that happened as soon as the power fc was plugged in. with stock ecu it was fine. Cant run stock ecu anymore though, as I have injectors and afm upgrade.

JimX Grand Master

JimX

Posted
Posted

Hmm, I can't see how your economy wouldn't suffer from turning that off. My idle isn't bad enough that I'm willing to sacrifice economy. I think I'll leave it on.

Maybe the O2 sensor is faulty? Or would the PowerFC detect the fault and give you a warning light? I'm sure mine is fixable without sacrificing economy, it probably just needs a professional to tune correctly.

Guest INASNT

Guest INASNT

Posted
Posted

I have a really bad idle problem which occurs at all different times. It will start surging from 400rpm to 2500rpm and after a while stall. I think mine is a vacuum leak somewhere coz it happened about a week after i drove with the pfc.

I havent driven my car for 7 weeks anyway, being built plus i am away for work, so hopefully i can sus the problem out when the new turbo etc finially goes on and i actually get to drive my car again.

R33man Enthusiast

R33man

Posted
Posted

After getting my Power Fc I noticed this a bit to. It does not idle as high when cold and then idles higher when warm. The factory ECU would idle at about 1400 RPM when cold and drop to 800 when warm. The FC idles at about 1200 RPM when cold but after about 30 seconds it drops to 1000 RPM and stays there. Ive also noticed it sometime varies its idle speed by 100 or so RPM. Not something I worry about but it just caught my attention.

JimX Grand Master

JimX

Posted
Posted

INASNT I did the 30 minute idle thing and it seemed ok, but then it started to have a mind of its own. Is there a way to reset the idle self-learning thing again without reseting the whole unit?

  • 2 weeks later...

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