vt loses power under acceleration, shudders/struggles to pick up speed...

[bobbie4]

Id say it would be the plugs,leads or if they are ok,one of the 3 ignition coils.These coils can run fine with no misfire or spluttering until they get put under load (going uphill or when accelerating fairly hard) then they can break down and cause the misfiring or spluttering.You can test the 3 coils with a multimeter,but Ive seen them show to be ok,but still cause misfiring. I keep a spare new coil just for testing purposes,just get the good coil,and swap it with the 3 coils ,one at a time, and drive it each time,if the problem goes away,then that coil that was removed is the problem.Its best to replace all 3 coils at the same time.Ive found fitting 3 new coils makes a big difference to the starting ,running ,and fuel economy,even when the coils are not faulty and are just old.They must slowly loose their performance over time until they get to a point where they die and cause mifiring.

 

[bobbie4]

Id say it would be the plugs,leads or if they are ok,one of the 3 ignition coils.These coils can run fine with no misfire or spluttering until they get put under load (going uphill or when accelerating fairly hard) then they can break down and cause the misfiring or spluttering.You can test the 3 coils with a multimeter,but Ive seen them show to be ok,but still cause misfiring. I keep a spare new coil just for testing purposes,just get the good coil,and swap it with the 3 coils ,one at a time, and drive it each time,if the problem goes away,then that coil that was removed is the problem.Its best to replace all 3 coils at the same time.Ive found fitting 3 new coils makes a big difference to the starting ,running ,and fuel economy,even when the coils are not faulty and are just old.They must slowly loose their performance over time until they get to a point where they die and cause mifiring.

Same problem with a VX on LPG and petrol, sluggish under load or going up grades would misfire. Changed the plugs and leads to no avail, then changed the coils on at a time, 2 were faulty, replaced all 3 and the old wagon is running well at 290,000K. Great advice, thanks!

 

[EQFish]

I had this problem with my vn v6. Ended up being the harmonic balancer & crank angle sensor changed it and she ran like a beast

Did your balancer make a noise when it happened? Like you lost power as you felt the belt slipping? Only wondering cause mines doing something similar...

 

[Chris Oogjes]

I have the same kinda problem, when taking off from a stand still, it has high lack of power and I put the boot into it, then she takes off or when I’m normally driving and I have to pick up speed quick, she lags a lot and just does not want to pick up speed at all and once again, boot into it and she goes, if I want to go up a hill, I need a run up for power,
But also noticed when I’m sitting on idle like fast food drive thru, idling ok for a bit then sometimes randomly when I have foot on brake, the revs tend to go up and down very lightly but well noticeable as if I’m actually reving up the car but I have the foot on brake

BTW it’s a s2 vt v6 sedan
Yeah high kms sitting on 303,xxx kms


I was thinkin Coil pack/DFI Module as I replaced plugs and leads at 290,xxxkms, I don’t know When coils and module was done last But I tested the coils with a multimeter set to 20k ohms and they were reading about 6k-6.2k and I’m pretty sure that’s normal
Fuel pump and filter where replaced just before Christmas last year, (bloody hate them clips tho, bloody bollocks)
Anyone have thoughts or ideas would be much appreciated
Cheers guys

 

[Sharp93]

Hey new here, not sure where to post sorry if not related to your post but complete newbie needs help I have 01 VT commodore that needs drivers seat replaced I can't find a VT seat what other models will go into a vt

 

[Chris Oogjes]

I been having sorta the same problem, there are day and times the car is fine but then there are days it struggles to pick up speed or go up hills but once I put the boot into it, it up and goes and other days after driving for a while it gets bad, also the idling, after the car has warmed up, when stopped at idle in drive still, car randomly starts sounding like I’m reving slightly when foot it on brake but only happens in a drive thru like maccas or KFC, I had the upper cylinder cleaning and throttle body cleaned along with the TPS switch replaced, was good at first but happening again, the mechanic (ultra tune) thinks it might be an internal problem with the transmission as it’s an older car, the trans does not slip at all tho and when the transmission was serviced, there was no metal in fluid, just dark old fluid, car is ex copper with a transmission police use but shouldn’t make a difference
I was thinkin idler sensor, plug and or lead, coil pack or even the DFI module
Peoples thoughts and opinions would be great thank you

 

[Lex]

Try your leads first.
If no good, then try dfi coil packs.