2015 VF SV6 LACK OF POWER (FLAT SPOT)

[Murdoch]

Hey greenac, the throttle body was filthy indeed as for the TPS I don't know if this has anything to do with the butterfly plate position but it certainly didn't look completely sealed to me (closed off) key out of ignition, before I started cleaning. (See the attached pic)
View media item 35 This was its position when i took of the tubing?

It would be interesting to see throttle position from driver's seat if I had some sort of instruction I'd attempt it, but to be honest what will I achieve with that, Holden's should be trouble shooting this issue not me. Anyways I'm going back to the dealership on Tuesday morning, if I have no joy with the service department I'll be asking to speak to the dealer principle. If I don't get anywhere with that I'll contact Holden Warranty directly and speak to them, maybe I'll try another dealership prior though. I'm just really pissed that I've spent over my budget on a practically new vehicle with bumper to bumper warranty till 2021 and my first warranty experience almost wants to make me throw up, sleepless nights, unnecessary stress I feel like thumping the sh#t out of something or someone. I've only had the car for just over a week and I haven't even been able to enjoy it. Anyway thanks again for going to all this trouble to try and help me out guys, this is a great community and I don't know where I would even start if it wasn't for you guys. Cheers

I thought these SIDI V6's injected fuel direct into the cylinder , (unlike other engines where injectors sit in the manifold) which woud reduce dirty intakes, throttle bodies??
Are they prone to blow by then if they are still getting dirty??

 

[greenacc]

Murdoch, apparently so yes they still get dirty, whether it's crank gases from the pcv valve or what I'm not sure. Direct injection also means there's no cool fuel lubricating the valves...

 

[Murdoch]

Murdoch, apparently so yes they still get dirty, whether it's crank gases from the pcv valve or what I'm not sure. Direct injection also means there's no cool fuel lubricating the valves...

interesting..

To the OP.
re adaptive learning etc. I can confirm that my V8 firms up gearshifting and shift points if i give it a squirt. It will then take a a few days to get used to my gentle driving habits again.
Not sure if the V6 boxes are different than the V8 ones however. If they are the same, well you might have to drive "spiritly" 'to get your desired outcome. Or get the box tuned as they do with V8's as well.
My 2 cents anyway.

 

[occtec]

interesting..

To the OP.
re adaptive learning etc. I can confirm that my V8 firms up gearshifting and shift points if i give it a squirt. It will then take a a few days to get used to my gentle driving habits again.
Not sure if the V6 boxes are different than the V8 ones however. If they are the same, well you might have to drive "spiritly" 'to get your desired outcome. Or get the box tuned as they do with V8's as well.
My 2 cents anyway.

So over the last couple days I've been driving spiritly and I reckon I'm starting to see some improvements today, so fingers crossed it's all it will need. EDIT: must have jinxed myself, lol.. on the way home after picking up the kids from school it seemed to lack throttle again anyway going into Holden's Friday.

 

[greenacc]

Re the variable inlet manifold tuning device. It comes in at about 4000+ rpm from somewhere I've read. You don't appear to be getting to that RPM point very easily.

My point is the Variable inlet manifold could be faulty, stuck in the high 4000rpm + position so producing no low end torque ?
Just an idea. These gremlins are usually hardest to trace when the computer can't detect there's a problem so doesn't throw any codes.

 

[Murdoch]

So over the last couple days I've been driving spiritly and I reckon I'm starting to see some improvements today, so fingers crossed it's all it will need. EDIT: must have jinxed myself, lol.. on the way home after picking up the kids from school it seemed to lack throttle again anyway going into Holden's Friday.

sorry to probably bust your bubble.
But i dare say they (holden) will do stuff all mate....

 

[SavVYute]

Hey, i just purchased a VF SV6 and i'm concerned regarding the lack of power on acceleration, more like a delay. I purchased it from a Holden Dealer in Adelaide, the car has just over 50k on the clock. I believe going by the service book that this was a rental :-( Murphy Holdings trading as 'Budget'. When you first take of in the car it seems all OK, but from then on it's not until you put your foot down about half way before it responds, like there is a delay after the fact. Travelling down a freeway at 100 if i want to accelerate further when i put my foot down its like there is a flat spot before it responds. I took it into holden service today after a couple of hours i received a call that the car is ready for pickup, when i asked what they found they said that this flat spot is when the auto trans is downshifting and further explained that i must be placing my foot back on the pedal during this shift hence why i'm feeling the delay. I feel like they are feeding me sh*t. The service guy mentioned that the trans will relearn overtime but this can take quite some time. Any feedback would be gratefully appreciated, just a s a heads up i did mention to them that the loan car which was same year but Evoke did not have any delay at all at any speed, you touch the pedal to accelerate and it just went. The service guy didn't have much to say regarding my experience, feeling really stressed out as I've spent over my budget already getting this car. One other annoyance I've found is with the steering wheel feeling loose not until your doing 80k+ that it seems to firm up a little, is this normal? Thanks guys, ive tried to explain as best to my ability as possible, i'm not really mechanically minded but feel that something is not right. Look forward to a more sensible explanation and hopefully a solution, maybe better fuel like the high octane 98 would make some difference??? i don't know.

Cheers

Your symptoms could be a faulty throttle position sensor.
The TPS tells the brains in the car if the throttle is at idle, wide open throttle and any position in between. And it also tells the rate of acceleration. That determines the enrichment of the fuel mixture (just like the accelerator pump does on a carburettor).
Also tells the auto transmission when to change down.....

 

[occtec]

Your symptoms could be a faulty throttle position sensor.
The TPS tells the brains in the car if the throttle is at idle, wide open throttle and any position in between. And it also tells the rate of acceleration. That determines the enrichment of the fuel mixture (just like the accelerator pump does on a carburettor).
Also tells the auto transmission when to change down.....

Thanks mate, I'll be sure to ask the question when it goes in on Friday to the dealership. Could the throttle position sensor also cause the trans to slip? Few times know I've noticed on acceleration from stationary position its slipped into gear.

 

[CalaisNQ]

Your symptoms could be a faulty throttle position sensor.
The TPS tells the brains in the car if the throttle is at idle, wide open throttle and any position in between. And it also tells the rate of acceleration. That determines the enrichment of the fuel mixture (just like the accelerator pump does on a carburettor).
Also tells the auto transmission when to change down.....

If was the TPS, I would have thrown a fault code by now.
I know with any commodore I've owned, v6 or v8, you have give the accelerator pedal a quick stab, of half or more throttle to get them to change down a gear or 2 quickly, otherwise it would have think about for couple of seconds, before doing so.

 

[SavVYute]

Few times know I've noticed on acceleration from stationary position its slipped into gear.

Don't understand what you mean by that. Can you clarify?

When you drop your car off to the workshop they will (or should) do a full service on it.
Once that's done they've got a baseline to work from and can rule out service items as a cause.
They should clean the air flow meter, check all engine hoses for air leaks, might fit new plugs and leads/coils if they've not been done (or check their connections are clean and tight if they have) and check the voltage range output of the TPS and other sensors with their diagnostics.