Rough Idle and Start Issue, My approach!

[RSTEP]

Hi all interested forum members.

Just before i get started I have read through lots of info about my VY berlina both on here and online.
The community support from this forum is by far the best by far so thanks everyone.
I decided against creating a large post re all my issues and what i will be doing, in favor of shorter more specific threads.
I tend to be quite specific and pedantic with details with what i am trying to do and my approach is if it has to come off the car while doing something else you might as well service it as well.

After having an absolute CRUDDY and disgusting not to mention complete waste of time, money, experience and an absolute destruction of my trust for my mechanic and liability i have over the months begun to learn more about my car and become more informed as not to get ripped of for the 5th or n'th time
Not to mention actually ensure the safety of myself and family.


Righto
The patient:
Holden Commodore VY Berlina 2002
Regularly serviced at all service intervals.
117K Km's on the clock
Received from my late father at 80k Km's on the clock
Fitted LPG at 100k Km's


The problem:
For the last few months the car has somewhat frequently started roughly on either Petrol or LPG and only ever after being left off for extended periods of time, 12 hours or so / over night. it does not matter whether its a cold or warm day.
The idle is not stable and is considerably lower then when i originally got it. RPM just over 600 and wavers.
The Bloody car shakes like it has the shivers.
On occasion its really bad and stalls especially when you try rev it just a little (My experience shows this really does not work, and stalls with a clunch! only once though)
Normal idle when working fine 750 to 800

The Workaround
Not to rev it out
Turn off the car and turn it back on and all is good revs' go back to normal.
Remove the battery and charge it slowly for a day or so (THIS REALLY MAD A DIFFERENCE)
beforehand the battery would only reach 13.7 V when car was idling, after the trickle charge its happily sitting at 14.1V 14.2 V at idle weeks after the charge
The battery is a standard, getting on in its age battery 2542 at CCA 555 RC 95. I had it tested and was sitting at 470 CCA, So still workable. will need to consider a change at some point. Not sure about the required CCA for the VY though.

My approach to fix the problem and Questions
If any other member could offer advice/experience and or additions to what i list below and or answers to questions that would be Great.
As mentioned above I have checked, charged, and conditioned my battery terminals and connectors which has made a nice improvement however i would like to do the following.

To address this i have found that it can be a number of issues related to the Air intake system and ignition so i will be removing and cleaning and these parts
The air box.
Air snorkel
MAF. (Clean with dedicated MAF solvent spray)
Throttle body (Clean with throttle body cleaner)
Air Filter (Inspect, clean or replace)
Spark plugs (check Gaps, resistances, insulation faults and cracks)
Spark plug leads and Boots (Clean, Check condition and resistance, look for deposits, use of electrical contact cleaner and solvents)
Starter Coils (Not Sure about these yet)
All fuses / relays (test and contact clean)
Clean inside the plenum.
Using a fuel additive to clean the fuel system. (Ill take before and after images of carbon buildup and breakdown)

Others:
Belts and tensioners

Questions if people can help me
1:The Throttle body. I have been unable to definitively confirm if i can use my throttle body cleaner on this part. I cant seem to determine if my throttle body has a lacquer coating that would be removed by the cleaner. Can anyone confirm that i can clean this part and that it does not have a lacquer coating.

2: Spark Plugs. They should have been changed many times by name but is there a way to check if they are indeed still the stock plugs. I think ford puts coloured dots on theirs to identify OEM parts for warranty purposes, Does Holden do the same for stock parts?

3: Spark Plug leads and starter coils. Can someone shed some light how to properly remove these parts either by recommended procedure or common practice?

4: Any suggestions on what i can use to block the bottom of the plenum chamber whilst i clean it with the throttle body cleaner? any better way or should it be removed entirely?

5: I have had a look at my air intake Box where the air filter sits, to me it does not look like it is sitting correctly and that the box has deformed. Does anyone have a pic they can share of a stock box and filter so i can compare and decide whether or not to replace my air box.



Any help you can offer or additions to the list above would greatly be appreciated.

Cheers
RSTEP

 

[HSV 671]

Ok, is it a 6 or 8 cylinder. I'm going to assume it's an auto... Is there a " check engine " light on the LCD, whether intermittent with a chime or check lamp staying on. Have you replaced anything so far. I've been through similar problems with my Clubby. I may be able to help you.

 

[Interloper94]

Fuel Filter clogged? extra charge on the battery could give the fuel pump just enough push to keep it going.
Nevermind, Read you have problem on LPG too.

 

[wortus]

I'd be checking for leaky injectors and also I'm assuming it's a V6? then there is a solenoid on the back of the intake manifold that purges the fuel tank vapour canister. This solenoid is meant to open when the engine is warmed up and the car is cruisng at speed. It opens and the vapour in the cannister is sucked in. Soemtimes this solenoid can get stuck open and the result is a bad idle. The hose may have even come off or split as soem other small hoses on the inlet manifold.
If you look for this solenoid and the hoses are all connected and good you can test to see if it is closign off properly or just pinch off the hose for a while and see if the car runs better.

 

[Pollushon]

Questions if people can help me
1:The Throttle body. I have been unable to definitively confirm if i can use my throttle body cleaner on this part.

Yes you can. The TB should ideally be removed to clean it properly including removal of the IACV which should also be thoroughly cleaned. This is actually one of the most common causes of the issues you've described.

2: Spark Plugs. They should have been changed many times by name but is there a way to check if they are indeed still the stock plugs. I think ford puts coloured dots on theirs to identify OEM parts for warranty purposes, Does Holden do the same for stock parts?

You mean plugs from the factory? Why would it matter? If in doubt swap them out, it'll cost you next to nothing. OEM are ACDelco.

3: Spark Plug leads and starter coils. Can someone shed some light how to properly remove these parts either by recommended procedure or common practice?

Leads can be tricky with the heat shields, but you just reef them off. Pays to grab a new set of leads (which sound like they could be due) in case they decide to crap out on removal. I'd leave the coil packs until after you clean the TB and replace the plugs in case that resolves your issue.

4: Any suggestions on what i can use to block the bottom of the plenum chamber whilst i clean it with the throttle body cleaner? any better way or should it be removed entirely?

As per Q1, take the TB off.

5: I have had a look at my air intake Box where the air filter sits, to me it does not look like it is sitting correctly and that the box has deformed. Does anyone have a pic they can share of a stock box and filter so i can compare and decide whether or not to replace my air box.

Probably easier if you take a photo of yours or you could just hit Google images.

 

[HSV 671]

"The Workaround
Not to rev it out
Turn off the car and turn it back on and all is good revs' go back to normal."

Yeah I had this issue with mine. Unstable idle and shaking car like it was missing bad, throwing the Traction control to off and was extremely low on power, not to mention fuel economy went through the roof. After replacing the Iac with no difference, it Turned out to be the Throttle Position Sensor. I bought an eBay part which made it worse. In the end I Had to take it to Holden. No other scan tool could talk to it and had to get genuine part and code it.

 

[RSTEP]

UPDATE:
Hi everyone.
Sorry for the late reply.
The issue seems to be resulved now after i checked and cleaned the spark plugs and MAF.
I will post more detailed findings and a few more surstions after i reply to people.
I would like to the thougher so others can use this thread.
At the moment Start ups are very easy with minimal turnover of the starter needed, Smooth and effortness when starting and smooth acceleration.
Does not vibrate as much at normal operation either and the revs at idle cold and warm are rock steady.
they are still a little low but runs really well at 730rpm idle warm.

Ok, is it a 6 or 8 cylinder. I'm going to assume it's an auto... Is there a " check engine " light on the LCD, whether intermittent with a chime or check lamp staying on. Have you replaced anything so far. I've been through similar problems with my Clubby. I may be able to help you.

V6
Auto 4 speed
No dash lights
No LCD icons or messages
No trouble codes as viewed fron the Dash LCD in cop mode.
Yes problem happenes every second to third start cold or warm after the car has been sitting for a while.
I have not personally replaced any items but it has been serviced. I asked for filters, oils, belts to be replaced and other little things, Yet i am finding now i have to check everything done as a lot has not been.

Fuel Filter clogged? extra charge on the battery could give the fuel pump just enough push to keep it going.
Nevermind, Read you have problem on LPG too.

You Have a valid point mate and yes extra charge so to speake can have the efect you mentioned. But yes it also occurs on my vapour draw lpg system. the fule filter has suposedly been changed.

I'd be checking for leaky injectors and also I'm assuming it's a V6? then there is a solenoid on the back of the intake manifold that purges the fuel tank vapour canister. This solenoid is meant to open when the engine is warmed up and the car is cruisng at speed. It opens and the vapour in the cannister is sucked in. Soemtimes this solenoid can get stuck open and the result is a bad idle. The hose may have even come off or split as soem other small hoses on the inlet manifold.
If you look for this solenoid and the hoses are all connected and good you can test to see if it is closign off properly or just pinch off the hose for a while and see if the car runs better.

Good pointand worth a check either way. I would nothaveexpected not would hvechecked this.... lol i am a beginner here.
since i have started here anything i have looked at and removed has been cleaned and serviced.

 

[RSTEP]

Pollushon ill reply in detail son, ineed to attend to my litle girl who is now getting into stuff she should not be. Lol kids
HSV 671 i was considering replacing all sensors on the throttle body.

 

[RSTEP]

Yes you can. The TB should ideally be removed to clean it properly including removal of the IACV which should also be thoroughly cleaned. This is actually one of the most common causes of the issues you've described.

Yes i have been finding out as much re it being a common cause so i will clean it HOWEVER my question was in relation to the existence of a possible lacquer coating that could be dissolved off by my TB cleaner 'solvent' that i have.
Do the TB assemblies in the vy 2002's have such a lacquer coating and thus need a detergent based cleaner instead of a solvent?

You mean plugs from the factory? Why would it matter? If in doubt swap them out, it'll cost you next to nothing. OEM are ACDelco.

Yep, I mean how can i tell if they are from the factory/stock/OEM/Original.
It matters because my mechanic should have changed these plugs over by now and probably a few times. I suspect he has now done the work that has been paid for
Yes ill be changing them out as soon as i have another moment as it was late when i was doing this so cleaning was my option.
Never heard of ACDelco I was expecting to find NGK Spark Plugs

Leads can be tricky with the heat shields, but you just reef them off. Pays to grab a new set of leads (which sound like they could be due) in case they decide to crap out on removal. I'd leave the coil packs until after you clean the TB and replace the plugs in case that resolves your issue.

Thanks for the advice with the leads, I was going to replace these when i finally get some more spark plugs.

As per Q1, take the TB off.

Is there a guide or procedure to take it apart LOL and put it back to together. I also have an additional bolt on Colette for the LPG system from SprintGas that needs to come off also.

Probably easier if you take a photo of yours or you could just hit Google images.

Will do, im currently grabbing my Pics off my Tablet, Ill post them up after this post.

Ill also post my findings re my Spark Plugs, It looks like my mechanic has installed the incorrect ones, but they still work. it may also be different to accommodate the LPG system.

It will be interesting to see what you all say.
Cheers
RSTEP

 

[RSTEP]

Righto. Some pics and my findings.

Spark Plug:
They were very dirty with carbon all over more then i would expect. Heaps of carbon on the threads of the plug and threads in the engine block.
No visible cracks or damage
Black carbon and white ash over. I have also never seen a spark plug that has a rust coloured coating.
Resistances around 5.3K ohms.
Spark Gab 0.76mm on all of them!!!! I was expecting 1.5mm as per service manual

I would not expect my plugs to look like they did at less then 17K from scheduled change out. Have a look and tell me what you think


Engine Right
Plug#: 2 Front: 5.1K Gap 750 uM
Plug#: 4 Mid: 5.7K Gap 780 uM
Plug#: 6 Back: 5.6K Gao 760 uM

Engine Left
Plug#: 1 Front: 5.35K Gap 860 uM
Plug#: 3 Mid: 5.1K Gap 760 uM
Plug#: 5 Back: 4.82k Gap 760 uM


Some examples of what I saw:
Spark Plug Sample Cylinder 2

Above: the spark plugs removed from Cylinder 2. these represent the general condition i found all of them in. They are GM branded with part numbers ... made in Japan

Above: Shows the rust like colour deposit on the spark plugs. May be be cause of different burn temperatures over its operational lifetime or bad fule? Who knows

Above: Air Box Filter Gap. Not so clear here but it bows out and at least you can see the gab between the plastic lip and Filter rubber seal.Is this gap normal
Above: Throttle Body as is and not cleaned. Is this the usual Look for a TB after 100k's

Above: Measured Spark Plug Gap at 0.76 mm average

Cylinder 2:

Above: The Spark Plug Port Crusted in Carbon and loose deposits and a look inside Cylinder 2

Above: A Better look inside Cylinder 2, This shows the general state of all cylinders. I think this is pretty bad lol




Now that it is running much better, I am running it on 98 Oct with Nulon Fuel system cleaner, Highway and city driving.

Additional Questions

So can anyone hell be if these are my original factoy plugs?
and
If my throttle body can be cleaned with a solvent cleaner (DOES it have any lacquer coats that will be dissolved off?)
If it can without damage of the lacquer if any, has anyone got a disassemble guide or recommendations before i just get screwdriver happy?


Cheers
RSTEP