VE OMEGA O6 When accelerating the revs surge up and down

[punternick]

When accelerating the revs surge up and down until you reach your cruising speed. Progressively getting worse used to happen only every now and then. Mechanic says it may have something to do with the coils...........any thoughts??

 

[Shamous69]

I am not sure what it could be but mine does this too, particularly around 1800-2200rpm and even more noticeable when cruising on highway up hills. My guess was going to be computer related but I haven't been game to go to holden to have it looked at for fear of losing a weeks wages!

 

[punternick]

What the mechanic said was that the diagnostic machine didn't pick up any fault but he said it is usually the problem.........looking at about $7-800. I'm not too keen to fork out either

 

[deano2]

perhaps spark leads?

 

[SavVYute]

When accelerating the revs surge up and down until you reach your cruising speed. Progressively getting worse used to happen only every now and then. Mechanic says it may have something to do with the coils...........any thoughts??

If it was a coil failing you would think it would misfire rather than surge. The diagnostics would throw a code for this.
Surging could be caused by a blocked injector.

 

[NVE_069]

U do know they dont have leads right ?

My mates does the exact same thing. When he drives it like misses but still increasers in power slowly. under heavy load it seems fine. ill get him to record it next time.

But I think it sounds spark related.

 

[Dz811]

Could you be more specific?

When you say the REVS surge up and down, sounds like a gearbox issue, not a misfire.
Besides, a misfire would bring up an error code for sure. Does the engine die and lose power? does it sound funny? Or does it change gear erratically?
Or do the engine revs just build up and then come back down again? I'm only going by what you're saying, but sounds gearbox related to me.

 

[SavVYute]

That's true Dz.
But if it's happening around the 80k/h mark when the torque converter locks up
I'd be checking the coils.

 

[Dz811]

I don't know alot about autos, just the basics, so please correct me if im mistaken.
But he says it is problematic on the way up to 80km/h? once it reaches cruise speed, then it stops? Is it possible that once the torque converter locks, and he is just cruising, then the problem is gone?

Again, im only guessing, because i doubt its coils or spark plugs. When coils died on my car, or my brothers car (he has an 05 vz wagon, still the same motor as mine or as the OP's) there was no gradual decline, they just failed there and then within about 10 mins of the first miss. And more importantly, the engine threw a code straight away, and ran like a dog, whether idling or driving.

It could also be the PCM, if it's failing to send a signal to any of the coils, but again the knock sensors should pick this up and throw a code...

Again, I'm not an expert, but i'd get the auto checked over

 

[denn91]

Hey mate my omega played up not 2 weeks ago
It was the coils and was making a cylinder misfire, and the check engine light was going nuts

Sorry I can't be much help