Welcome to Just Commodores, a site specifically designed for all people who share the same passion as yourself.

New Posts Contact us

Just Commodores Forum Community

It takes just a moment to join our fantastic community

Register

VT Sputtering at idle

madrx3boy

Member
Joined
Aug 25, 2008
Messages
78
Reaction score
0
Points
6
Location
New Zealand
Members Ride
98 VT Acclaim
Hi everyone,

My VT 3.8 Ecotec has had a bit of a sputter since I got it 1.5 years ago. For a long time I never really noticed it unless I walked round to the back of the car, then I could faintly hear the exhaust sputtering (sounds like a pffft sort of noise). I didn't think too much of it at the time

But lately it's been a lot more noticeable - now I can feel the car shaking at idle - and now it's really starting to bug me. One by one I've replaced the air filter, plugs, and leads but it's still doing it.

I can't say I notice anything while the engine is under load - maybe a slight decrease in performance, hard to say due to the fact that the problem was already there when I got the car, and partly because it's gotten worse slowly over a long period of time.

I've got a couple more ideas of what it could be, but want to get some advice before I start replacing parts unnecessarily.

I'm thinking either: Coils (How can I test them?), Fuel Filter, Cracked vacuum hoses. Although I would have thought that if it was any of those, then it would be even more noticeable once I open up the throttle more and more?

Any ideas will be much appreciated!
cheers
 

Nut Kracker

Donating Member
Joined
Oct 18, 2012
Messages
4,760
Reaction score
135
Points
63
Age
61
Location
Echuca Vic.
Members Ride
VT SS 304ci (195i)
Why not think out of the square for a change and check that the muffler or cats aren't blocked.
 

VTSS304

New Member
Joined
Oct 6, 2013
Messages
90
Reaction score
1
Points
0
Location
Australia
Members Ride
VT SS 5.0L Manual
As Nut Kracker said it could be a blocked exhaust section. Also you could try something like and upper engine clean (comes in an aerosol and you spray it into intake while the car is running, then let it sit for 15-20 mins, then it will be hard to start and will blow smoke for a few minutes but then should either improve from before or go back to how it was) It could still be a coil because at higher revs the spark might be strong enough to jump the break and run as normal. Possibly a partially blocked injector?
 
Top