VY s pac series 2

[jdcasagrande]

ROUGH IDLE ON COLD START!

Hi Guys and Girls,

I currently have a 2003 VY s pac series 2, and ever since ive had the car it has an extremely rough idle on a cold start up. Basically the rev go up and down for about a minute whilst the engine shakes violently, and then the idles settle down and run smoothly.

I have consulted a mechanic about this and he said that most turbo and supercharged cars have a rough idle on cold starts.

Has anyone experienced a similar problem to this? and what step should i take to fixing it?

cheers

[Mohi]

hi mate
I gt a 03 Vy , had same trouble with it and spent like $600buks but couldnt get it fixed, tried with holden but they said all Vy's had a bit of rough idle , i got my plugs, leads , coil pack all replaced with full service but had no luck , it improved a bit but not much, so i am just living with it....(
but mine is not a super charge or turbo...but i wish i had .

[TMM]

What kind of fuel do you guys run?

My dads VY Ecotec is hard to start (requires 2-3sec of cranking to start, sometimes even longer). Sometimes when you start it, it sounds like its running on 5 cylinders and shakes like a bitch until you give it a rev, then it idles properly. He uses Shell 91 and Woolworths (Caltex) 91.
My Ecotec was the same up until I started only using BP 95, and now it always starts with less then 1 second of cranking, and idles smooth even when freezing cold.

[jdcasagrande]

Hi, i currently run standard shell unleaded which i think is 91 octane. I dont think this is the issue, so far from what ive gathered the VY holdens rough idle may be caused by the ECU, the ECU can be reset by anyone, theres instructions on the internet how to do it, i havn't got around to doing this yet.

another suggestion was that the battery may be on its way out, and the rough idle is caused by low battery power until the alternator kicks in and gives the battery some life. Another suggestion was also that the air vacuum lines had a crack or may have come apart, ive checked the lines and they are all fine.

MOH: i think your problem would most likely be worn engine mounts, apparently the VY engine mounts are only good for 6 years, once they get too old they lax and cause the engine to idle rough. Mine are slightly laxed at the moment too, but my idle on cold start pritty much shakes the whole car and then comes good after 30 seconds.

any more ideas would be appreciated

[a1k3m1]

i would say myself to give it a few tanks of V-Power or some high octane premium petrol, and some injector cleaner.. My VY runs like crap when i use anything less than 95 Octane, feels like its got getting enough grunt to spin the engine around... But then when i use the premium stuff it works heaps better.. And if you always go to the same petrol station .. try going to a different one as the one your using might have a shitty batch of petrol or something

im Pretty sure it has nothing to do with the alternator or battery..

[ausrs]

funny i also have the same issue with my vy series 2 wagon ,i cleaned the throttle body and it stopped it for a day or so .then it came back i then changed the fuel filter and it went away for about 2 weeks and it has just come back ..........i am going to run a couple of tanks through with injector cleaner and see what happens ............with what i have done it is definitely NOT electrical
1st start of the day feels like it is on 5 cylinders ..from then on it is perfect !

[Dr HaxZaw]

if you run the car on anything lower than 95 i find its a bit of a bitch cold... i just stick with v-power now to save myself the feul and annoyance

[jdcasagrande]

at first i thought electrical because the dash lights dim and go bright while the car is running rough and then goes back to normal when the revs come good.

I will replace the fuel filter and run a full tank of V power this week and il post the results.

How do i clean the throttle body?

[jdcasagrande]

ok so i cleaned out the throttle body, and i replaced the fuel filter, and filled up the car with Shell V power 98 octane along with some injector cleaner, ive gone through about a qaurter of the tank of fuel so far and the car still has a violent shuddery idle on start up. I have noticed the car does idle like this for a shorter time, down from like 20 seconds to maybe 12 seconds (rough guess). Ive also noticed by changing the fuel filter the car is more responsive and deffenetly has a lot more power (possibly due to the V power fuel also).

Any more suggestions as too whats causing this violent idle on start off? it seriously only lasts a few seconds, but without my foot on the accelerator, the car comes close to stalling. The problem is less noticable in warmer weather.

cheers