VY SS Shuddering when idling???

[shaunandcourt]

Purchased VY SS Oct 2008, immediately put on a cold air induction kit. approx 5 months ago it started displaying *CHECK ENGINE LIGHT*, then the troubles with mechanics began, after constant diagnostics, each saying a different code, most common was the Air flow sensor, we were advised to remove the cold air intake, assured it would fix it. Then after it still didn't fix it, and slowly began running rougher, we were told by another mechanic it was the O2 sensors, replaced both sensors immediately, the next day, the check engine light came back on. Now our mechanic is saying it could be the spark plugs and leads. I feel like we are getting ran back and forth, we just want it to be reliable as my wife and I are expecting our 2nd kid in 2 1/2 months.
The car starts fine, as soon as you reverse it out of the driveway it chugs, then once in drive it is as though it wants to stall and is hesitant to take off. When you stop at lights or intersections the car shudders when revs sit between 400/600 RPM. The check engine light only comes on once the car is warm, usually 3-4 mins after starting and when the temp has reached the lower part of the first 1/4 on the temp display. We have suspicions that it can be a vac hose, but which one? Also have read from other threads it could be the fuel filter? Any ideas?
Note, one thread I read said it could be to do with Traction control??? But this is an ex cop vy ss and we have been informed it doesn't have traction control in it?
Cheers for any help, it's appreciated =)

[Kingston_99]

mine did this all the time before as well.

i did a few tests and found out when i disconected the TPS (throttle position sensor) then check engine light came on.

if you have a mate with the same motor, try borrow his TPS and put it in yours and run it till it gets warm and see if that fixes the problem.
also could be the stepper motor. (dose it shudder with aircon on/off?)
also check all Vac lines/hoses for lose contections and signs or wear and tear on hoses.

also check all leads have a good conection to coil pack and spark plugs. my #2 lead allways falls of the spark plug and makes the car missfire and shudder, but no engine light comes on.

good luck with it mate

[Chrisvyss]

when all else fails suck it up go to holden and get it plugged it in, they built it they know how to fix it they just charge like money is free

[soop]

Crank sensor.

[Kingston_99]

when all else fails suck it up go to holden and get it plugged it in, they built it they know how to fix it they just charge like money is free

yeah ripped me off $75 to hook up their computere and see #2 cyclinder missing. check lead and see its have poped off. put the lead on correctly and fixed.... something i should if checked my self. could of had half a tank of fuel