VE Surging under load on petrol - misfires on lpg

[ploth]

New here, never owned a commodore myself but had a VT Berlina Wagon & this VE for the missus. Don't hate on me I've owned LOTS of Holdens (pre commodore, HQ series, Torahs, EJ, HT etc) and only one ford I was given as a paddock basher for the kids. Didn't last long lol.

Just hoping someone can help -

VE (v6) starts & runs smooth, but if you put the boot in, it surges like CRAZY. Maybe it's better to describe it as the motor cuts in & out. i.e. it's like stabbing the accelerator for a second and off for half a second and keeps repeating. Feels like the engines mounts will snap. And very hard to make spin.

If you accelerate gently up to 3000/4000 revs it's fine.

Switch over to lpg and it feels like it's running crazy rich - or at least missing on a cylinder or two through the whole rev range but doesn't sure / cut in & out. Just hard to get to pick up speed.

Have read a number of threads here about O2 sensors, TPS, air leaks etc but thought someone in the know would be able to point me in the right direction before I go replacing everything & still have same issue...

Would O2 sensor explain the difference in issue between petrol & lpg?

Cheers

 

[MYVESSV8]

filters on the gas system, ok to steady accelerate but not good enough for boot full
plugs, etc

 

[whats up]

New here, never owned a commodore myself but had a VT Berlina Wagon & this VE for the missus. Don't hate on me I've owned LOTS of Holdens (pre commodore, HQ series, Torahs, EJ, HT etc) and only one ford I was given as a paddock basher for the kids. Didn't last long lol.

Just hoping someone can help -

VE (v6) starts & runs smooth, but if you put the boot in, it surges like CRAZY. Maybe it's better to describe it as the motor cuts in & out. i.e. it's like stabbing the accelerator for a second and off for half a second and keeps repeating. Feels like the engines mounts will snap. And very hard to make spin.

If you accelerate gently up to 3000/4000 revs it's fine.

Switch over to lpg and it feels like it's running crazy rich - or at least missing on a cylinder or two through the whole rev range but doesn't sure / cut in & out. Just hard to get to pick up speed.

Have read a number of threads here about O2 sensors, TPS, air leaks etc but thought someone in the know would be able to point me in the right direction before I go replacing everything & still have same issue...

Would O2 sensor explain the difference in issue between petrol & lpg?

Cheers

New here, never owned a commodore myself but had a VT Berlina Wagon & this VE for the missus. Don't hate on me I've owned LOTS of Holdens (pre commodore, HQ series, Torahs, EJ, HT etc) and only one ford I was given as a paddock basher for the kids. Didn't last long lol.

Just hoping someone can help -

VE (v6) starts & runs smooth, but if you put the boot in, it surges like CRAZY. Maybe it's better to describe it as the motor cuts in & out. i.e. it's like stabbing the accelerator for a second and off for half a second and keeps repeating. Feels like the engines mounts will snap. And very hard to make spin.

If you accelerate gently up to 3000/4000 revs it's fine.

Switch over to lpg and it feels like it's running crazy rich - or at least missing on a cylinder or two through the whole rev range but doesn't sure / cut in & out. Just hard to get to pick up speed.

Have read a number of threads here about O2 sensors, TPS, air leaks etc but thought someone in the know would be able to point me in the right direction before I go replacing everything & still have same issue...

Would O2 sensor explain the difference in issue between petrol & lpg?

Cheers

 

[whats up]

 

[blackve76]

Sounds like a misfire, plugs coils would be first, just changed coils plugs on my dual fuel at 190k(plugs done at 95k) cat wad running fine but thought should do coils as well, car running sweeter than ever

 

[kwaka738]

Sounds like ignition problems to me also (ie plugs and/or coils).

From threads I've read on LPG cars the ignition system needs to be in good condition for it to run well whereas running on petrol it will run slightly better with the same ignition system. So the symptom you have described (ie poor on petrol, terrible on gas) fits the model of an ignition system in need of maintenance.

 

[ploth]

Thanks guys - got to it today.
Seems to have been two issues:
The air inlet pipe had multiple cracks, the lpg dispersing ring had fallen out.

Runs great again. I tweaked the lpg mixture, has never run better.