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

Oxy sensors cause rough idle?

2005vzute

Djabringyagrogalong
Joined
May 26, 2010
Messages
362
Reaction score
3
Points
0
Age
28
Location
Glenfield 2167
Website
forums.justcommodores.com.au
Members Ride
2005 VZ Ute M6
G'day,
so since i've bought my car its had a rough idle, it felt like a vacuum leak somewhere before because it wasn't a major rough idle and would sometimes stopped, i sealed everything up, tested everything, no vacuum leaks, still a rough idle though...i've run fuel injector cleaner thoruhg my tank a coupla tank, still nothing, maf sensor has been cleaned, new filter etc...finally got around to doing my spark plugs last night hoping it would fix it...no luck...its feeling more n more like a misfire as the engine kicks more violently now everytime i sit in it...all i could think of now is possibly oxy sensors? would they cause a misifre/rough idle?

does anyone have any ideas on why it could be idling rough/misfiring

cheers everyone:)
 

bigdaddycool

Member
Joined
Sep 5, 2008
Messages
500
Reaction score
9
Points
18
Location
Brisbane, Queensland
Members Ride
2009 VE SS SILVER SEDAN
My car has a similar issue:

1. Replace throttle body 90 degree hose (full proper part)
2. Coil packs? (mine car doesn't miss when accelerating only on idle so dunno if they need doing).
3. Raise idle to 630rpm if you have VCM Suite
4. O2 Sensors may cause your car to 'lean out' fueling wise, this would cause this sort of event. Easy way to check, unplug all 2 or 4 (depending on your model) of the O2 Sensors, reset the ECU (remove the 10amp ecu fuse in the engine fuse box for 15 seconds, and reseat). Take the car for a drive for an hour (to let it relearn things) and then see how it is for a few days. If the issue goes away then it's your o2's probably, if not........ something else. It should use a tad more fuel as the o2's will be off so the car should run richer and only off the MAF sensors temporarily.
5. Battery condition - need power to run injectors and electrics?
6. Buggered if I know, goto holden? :D

PS. Dont worry about a powerchain message if you get one, just leave it there for a few days. Once you plug back in your o2's all you have to do is another reset of the ECU via the fuse and the powerchain message should go away.
PS2. If you haven't reset your ECU since you got the car, maybe just start there.
 

ADR 40

Member
Joined
Nov 14, 2010
Messages
42
Reaction score
2
Points
8
Age
56
Location
South Oz
Members Ride
VZ Lumina..... VEII Equipe Sportswagon
6. Buggered if I know, goto holden? :D
.

Not a bad idea.... and it doesn’t have to be a Holden dealer.
You can eliminate a whole lot of possibilities if you take her in to have a diagnostic check.
Once they’ve plugged her in they should be able to let you know what is causing all the grief.
It will save you a lot of time (and money) trying to pin point it yourself.
 

2005vzute

Djabringyagrogalong
Joined
May 26, 2010
Messages
362
Reaction score
3
Points
0
Age
28
Location
Glenfield 2167
Website
forums.justcommodores.com.au
Members Ride
2005 VZ Ute M6
yea true...i might try resetting the ecu, if its still shitty i'll try the oxy sensors...its a brand new battery too pretty much haha, only about 4 months old:p
 

Warrior

New Member
Joined
Nov 1, 2005
Messages
23
Reaction score
1
Points
3
Location
Brisbane
Members Ride
VZ one-tonner
I've had same problem since my car was new. It get worse when I use Woolworths 95 oct. fuel. I'm now using BP ultimate only which has reduced the shaking to only a bit now and then. I'd like to see or hear from anyone who has solved the problem. Holden certainly can't.
 

bigdaddycool

Member
Joined
Sep 5, 2008
Messages
500
Reaction score
9
Points
18
Location
Brisbane, Queensland
Members Ride
2009 VE SS SILVER SEDAN
lol u could get some carby cleaner too and clean your throttle body and intake piping etc........... along with the maf sensor .......... oil builds up and causes rough idle ........ just another hint
 
Joined
Jul 24, 2013
Messages
4
Reaction score
0
Points
0
Location
United Arab Emirates
Members Ride
Lumina S
My Lumina S does the same

lol u could get some carby cleaner too and clean your throttle body and intake piping etc........... along with the maf sensor .......... oil builds up and causes rough idle ........ just another hint

As you know Chevorlet Lumina S another name of Holden VZ SV6. Mine engine in same 175 kW Alloytec. Mine one exactly does the same if you give throttle there are no jurks. But some time i keep it on idling some time it start kicking and kicks pass all over the body and they are random some time engine goes very smooth sometimes issue feels very frequently. For this i replaced all spark plugs. I checked all the circuits for leaks checks EVAP solenoid PCV everything is fine but i come to know that during problem if i disconnect EVAP intake breather car get smoother. but EVAP operation is normal as it controlled by ECU and there is no function problem i feel. One thing observe that the problem varies from gas station to gas station some gas stations fuel gives more problem compare to other. Recently i install Fuel saving magnetizer and i have good results engine get more smoother but the problem still presist. So, i come to conculsion this the problem of ECU firmware, it has some issues to control the engine.

So, that is all.
 
Joined
Jul 24, 2013
Messages
4
Reaction score
0
Points
0
Location
United Arab Emirates
Members Ride
Lumina S
I have gone through all of the experiences, all of you guys have went through. I am here in UAE and the same holden commodore vz sv6 is marketed as as Cheverolet Lumina S. I bought a used one three years back. and from the very beginning i was facing the same rough idling problem. After the engine takes operating temperature on idling it starts shaking momentarily. To solve this issue i went through nearly all forums and public opinions. I did the following to fix it.

1. Spark plugs replaced with new one.
2. Checked for vacuum leaks.
3. Then i run OBDII diagnostic and analyse the real time trends. So i come up with following

i. MAF reading is not steady.
ii. Short term fuel trim is richer for one bank
iii. Short term fuel trim is leaner for the 2nd bank.
iv. Both trims are fluctuating badly.

To fix these issues i did the following:

4. Cleaned the throttle body with ACDelco Carburetor conditioner.
5. MAF cleaned with CRC Electronic Cleaner.
6. Then i reset the computer by just battery terminal disconnect.
7. In full tank i put 2 bottles of ACDelco Fuel Injector Conditioner.

And the rough idle issue is fixed. Specially if the AC is not running. Now if i connect the scanner the fuel trims for both bank remains at 0% with +1 or -1% fluctuation. Also MAF reading are much stable and reading g/s is improved. For example before cleaning it was giving 3.0g/s and now 3.8 or 4.0 g/s. Now i am feeling car is more powerful gives very quick response to the paddle and fuel economy is improved.

So these are my findings and may be it can help someone.
 

Benboy

Well-Known Member
Joined
Aug 26, 2007
Messages
2,466
Reaction score
96
Points
48
Location
Hill River, SA
Members Ride
2007 SVZ Wagon
Put a couple of bottles (not at the same time) of Fuel System Cleaner through your fuel tank. If that doesn't fix the problem, then clean the MAF Sensor, Throttle Body, check Air Cleaner is not restricted etc. I have begun using Shell distributed fuel with what I believe is smoother/cleaner running.
 
Top