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

VY L67 Flat Spot/Hesitation ONLY when cold on acceleration.

Lex

Well-Known Member
Joined
Sep 19, 2012
Messages
5,753
Reaction score
5,000
Points
113
Location
Geelong Victoria
Members Ride
VT Executive S1 V6 6 speed Auto Wagon
Yes,
Checked the Plug and loom, in case it had a damaged, burnt pin or socket.
I did that this afternoon after I pulled the DFI off, which gave be a bit of roon to check the plug and wiring.

Were it NEVER misses a beat when warmed up, it actually runs perfectly.
Did you change the intake manifold gasket awhile ago (6 months ago?). Somebody did. The person said it fixed a miss.
The thinking on it is when cold there is a minor leak. When at normal operating temperature, the gap seals up. So no miss?
Only theory?
 

krusing

Well-Known Member, Possibly for the wrong reasons
Joined
Jun 21, 2014
Messages
5,345
Reaction score
3,936
Points
113
Location
Melbourne, Bayside
Members Ride
2002 VY L67 Calais Sedan, 2012 VE L77 Calais Wagon
Did you change the intake manifold gasket awhile ago (6 months ago?). Somebody did. The person said it fixed a miss.
The thinking on it is when cold there is a minor leak. When at normal operating temperature, the gap seals up. So no miss?
Only theory?


Yes I did,
I did a full LIM and Supercharger Gasket Kit,
As I was hoping it was that of the Hesitation,
where it did fix the fast idle when cold,
and the orange marshmallow milkshake in the radiator.
 

krusing

Well-Known Member, Possibly for the wrong reasons
Joined
Jun 21, 2014
Messages
5,345
Reaction score
3,936
Points
113
Location
Melbourne, Bayside
Members Ride
2002 VY L67 Calais Sedan, 2012 VE L77 Calais Wagon
@Lex,
I am beginning to think its a head gasket, as I was hoping its wasn't,
As the Water was very rusty, but not thick.
With everything I have thrown at it.
Both Belts [Alternator & Supercharger]
Supercharger Service Kit [from Mace Engineering - last year]
Full LIM Gasket Set,
Replacement Vac hoses
[Bypass the Boost solenoid at the back of the Left head]
TPS
IAC Valve
Air Filter
Fuel Filter,
Plugs,
Leads,
DFI.

Not much left to replace now :confused:

No DTC's displaying or in history.
What I might do now, is pull the Supercharger Belt off, and road test it,
might run like a bucket of bolts, but see if it still hesitates.
 

Lex

Well-Known Member
Joined
Sep 19, 2012
Messages
5,753
Reaction score
5,000
Points
113
Location
Geelong Victoria
Members Ride
VT Executive S1 V6 6 speed Auto Wagon
@Lex,
I am beginning to think its a head gasket, as I was hoping its wasn't,
As the Water was very rusty, but not thick.
With everything I have thrown at it.
Both Belts [Alternator & Supercharger]
Supercharger Service Kit [from Mace Engineering - last year]
Full LIM Gasket Set,
Replacement Vac hoses
[Bypass the Boost solenoid at the back of the Left head]
TPS
IAC Valve
Air Filter
Fuel Filter,
Plugs,
Leads,
DFI.

Not much left to replace now :confused:

No DTC's displaying or in history.
What I might do now, is pull the Supercharger Belt off, and road test it,
might run like a bucket of bolts, but see if it still hesitates.
Have you done a compression test yet? One cold, one hot. If so, what was the result?
 

krusing

Well-Known Member, Possibly for the wrong reasons
Joined
Jun 21, 2014
Messages
5,345
Reaction score
3,936
Points
113
Location
Melbourne, Bayside
Members Ride
2002 VY L67 Calais Sedan, 2012 VE L77 Calais Wagon
Have you done a compression test yet? One cold, one hot. If so, what was the result?

No not yet,
I do have some very old gauges back from the Red 179 days my Father left me, not sure if they will sure if they will fit the spark plug whole, being the plugs wholes are smaller.
It did cross my mind last week thinking what should I do next, Plugs, Leads etc etc
That's when I though I will wait till I replace the spark plugs, and see the condition of the old plugs.
Which they all looked in the same condition, which wasn't to bad, thinking if any one of them is different, it could be the heads gasket on that cylinder.
Probably best to do a dry compression test, and then a wet one.
 

Lex

Well-Known Member
Joined
Sep 19, 2012
Messages
5,753
Reaction score
5,000
Points
113
Location
Geelong Victoria
Members Ride
VT Executive S1 V6 6 speed Auto Wagon
No not yet,
I do have some very old gauges back from the Red 179 days my Father left me, not sure if they will sure if they will fit the spark plug whole, being the plugs wholes are smaller.
It did cross my mind last week thinking what should I do next, Plugs, Leads etc etc
That's when I though I will wait till I replace the spark plugs, and see the condition of the old plugs.
Which they all looked in the same condition, which wasn't to bad, thinking if any one of them is different, it could be the heads gasket on that cylinder.
Probably best to do a dry compression test, and then a wet one.
I thought you had already changed plugs, leads?

Have you ohm tested the leads?

You can buy adaptors, for the compression tester.
 
Last edited:

Immortality

Can't live without smoky bacon!
Staff member
Joined
Apr 15, 2006
Messages
22,472
Reaction score
19,901
Points
113
Location
Sth Auck, NZ
Members Ride
HSV VS Senator, VX Calais II L67
Can't you buy test kits that check for combustion gases in the coolant? Rather than a head gasket issue I'd be thinking a cracked head as this was a reasonably common issue but was under the impression the VY's used a later casting that kinda resolved that issue.
 

krusing

Well-Known Member, Possibly for the wrong reasons
Joined
Jun 21, 2014
Messages
5,345
Reaction score
3,936
Points
113
Location
Melbourne, Bayside
Members Ride
2002 VY L67 Calais Sedan, 2012 VE L77 Calais Wagon
Can't you buy test kits that check for combustion gases in the coolant? Rather than a head gasket issue I'd be thinking a cracked head as this was a reasonably common issue but was under the impression the VY's used a later casting that kinda resolved that issue.

Yes there is kits to test If there Is combustion gas’s in the coolant,
I think about $40 / $50.
They are a sold on eBay, as I did my research on there some time ago when the coolant wasn’t looking to well.
 
Last edited:

krusing

Well-Known Member, Possibly for the wrong reasons
Joined
Jun 21, 2014
Messages
5,345
Reaction score
3,936
Points
113
Location
Melbourne, Bayside
Members Ride
2002 VY L67 Calais Sedan, 2012 VE L77 Calais Wagon
I thought you had already changed plugs, leads?

Have you ohm tested the leads?

You can buy adaptors, for the compression tester.

The plugs and leads where done some time ago,
At 160,000 k’s, (as it’s almost done 190,000 k/m’s)
as I thought about doing them again if I was going to do head gaskets,
but opted to do the other hardware around the heads first, hoping it would fix the issue.

I did test the resistance of the leads some time ago
As for the adaptors, not sure, as they at old,
and in PSI :eek:
 
Last edited:
Top