Vy v6 Rough idle

[VY_SP4C]

Hi

I have a 2004 vy spac ecotec 3.8 i have come across a rough idle while in drive parked at lights or stopped in traffic it is slightly there in neutral/park if i bring the revs up to about 1000rpm it dissapears. it has progressivly got worse when plugged in to a computer by a mechanic he came up with nothing, i have so far changed coilpacks, leads, plugs, engine mounts and the gearbox mount i have the twin cat setup someone told me this could be the problem? Also i noticed while the car was running if i unplug the air temp sensor the maf sensor or the IAC sensor nothing seems to change it still idles exactly the same.

any help would be appreciated Thanks

 

[acarmody]

Hi

I have a 2004 vy spac ecotec 3.8 i have come across a rough idle while in drive parked at lights or stopped in traffic it is slightly there in neutral/park if i bring the revs up to about 1000rpm it dissapears. it has progressivly got worse when plugged in to a computer by a mechanic he came up with nothing, i have so far changed coilpacks, leads, plugs, engine mounts and the gearbox mount i have the twin cat setup someone told me this could be the problem? Also i noticed while the car was running if i unplug the air temp sensor the maf sensor or the IAC sensor nothing seems to change it still idles exactly the same.

any help would be appreciated Thanks

Sound like a vacuum leak.

 

[NU13]

Is it like a shudder everyone 4 or 5 seconds?

 

[VY_SP4C]

i have checked all the vac hoses and cant seem to find a vac leak and yeah there is like shudder every four to five seconds.

 

[NU13]

My SS does this as well. I drove my bosses Acclaim last week and his does it as well. Apparently it's common. I've been chasing the same thing from when i got SS but have now realized that many do it.

 

[someguy360]

I can also agree this seems to be a common thing with the VY.

I have driven a few VY V6's and they all do it, unless its a full on missfire and causing issues I wouldn't worry about it.

the ecotec was never a smooth engine to begin with.

 

[VY_SP4C]

iv had a vs a vt and now this vy ecotec and this is the only one that has done it it is a constant vibration that is quite annoying that like surges every four to five seconds and it only does it in drive or reverse its not so bad in park or neutral.

 

[someguy360]

iv had a vs a vt and now this vy ecotec and this is the only one that has done it it is a constant vibration that is quite annoying that like surges every four to five seconds and it only does it in drive or reverse its not so bad in park or neutral.

yeah, i know the feeling, may be a VY thing.

90% of people don't really notice it, but some people that are anal about anything vibration, tick, knock or clunk me included, these things piss me off to the point where I must fix them where most would ignore them

 

[SavVYute]

I could be wrong, but I think a slight random 'stumble' at idle is a normal trait of the series II VY ecotec engine management system.

But if it is something new that the car never did previously you might look at investigating something like
*an intake manifold gasket leak
*slight exhaust leak upstream from one of the catalytic converters
*getting the injectors cleaned and serviced with new seals

What does it drive like?

 

[VY_SP4C]

yeah it definately wasnt there when i first got the car it drives fine once the the revs go up you wouldnt even know it had a problem i have read about the vy common random stumble but that is on top of the constant vibration through the car.

and i will check those things out thanks