I've noticed you guys talk alot about injectors..... what are the signs of wear or problems with injectors and also what are the non-turbo injectors worth reco or new each??? Are they hard to replace?? Just curious cause I don't know much about them and wanna know what to look for !! Some original photos have not been recovered yet.

The injectors are always under high pressure, and after a while the seals inside the injectors start to fail. This is normally noticeable by fuel leaking from the body of the injector, and this is the main reason people replace injectors, either that or to achieve increased flow rates. While fuel can leak from the short piece of rubber hose joining the injector to the fuel rail, more often than not it's from the internals of the injector itself, especially if they're the original items. If they're leaking slowly, you should still see fuel stains on the manifold below the injectors. It's worth replacing them if they are leaking, because they'll only get worse, and eventually the pressure will cause a major fuel leak, and we all know what happens when fuel goes exploring in a hot engine bay! 8O It also means they're not sealing properly, and not all the fuel is going where it should. As injectors get old, their spray pattern gets poorer, meaning the fuel tends to come out in drops and dribbles, rather than a fine spray. This means the heat in the combustion chamber doesn't vaporise the fuel as easily, which means not all the fuel is being turned into power, i.e. reduced power and probably increased fuel consumption to compensate. The other problem is that they all foul at different rates, so while the oxy sensor may be seeing the right mixture, it doesn't necessarily mean that each cylinder is getting the right amount of fuel. You could have 3 too lean, and 3 too rich, if some are much worse than others, but the computer will still see the right mixture when all 6 cylinder's gasses are combined in the manifold / turbo. You can get injector cleaner and pour it in the tank, which is OK for maintenance, but a much better method is to remove the injectors and get them cleaned out of the car - that way the flow pattern and leaks can be tested properly. Removing the injectors requires separating the plenum chamber from the manifold (there's the bolts you can see from the top, 4 I think, and two long ones underneath on the engine side of the manifold) and disconnecting all fuel connections. I got mine off in about an hour. It's worth replacing the rubber injector sealing rings at the same time, and if any of the hard black plastic injector holders are broken, replace them too. If they're cracked, the nose of the injector doesn't seal against the manifold properly, and air can be sucked past the injector under high vacuum, giving you a nice little untraceable miss at idle - had me stumped for months! Replacement injectors vary in price, starting from around $150-$200 each for equivalent or genuine items (when I say 'genuine', I mean the same as what's fitted, but not from Holden - expect to pay upwards of $400 per unit if you get them from GMH - but then you can buy a 'genuine' VL turbocharger from Holden and pay about $4200 - that's one expensive T03!). Non-turbo injectors don't provide as much flow as turbo ones, so don't bother with them unless you've got a NA VL. The genuine / equivalent injectors are good for about 15psi, beyond that and pinging can become an irremovable problem. The simplest upgrade if you want to go past 15psi, is Bosch 036's from what I understand. They're a similar price but have about 20% more flow than standard turbo injectors, so even if you're around 15psi and looking to replace your injectors, I'd recommend them just to be safe. They're a direct replacement, so there shouldn't be any fitting problems. Dave Keen from TurboTune (8297-1030) gave me this information several months ago, so he can probably answer any other questions you may have regarding the 036's, or a more potent upgrade if you're after that. Good luck!

Thanks sleeper.... I'm gonna keep my eye out for these symptoms.... I have a N/A Calais...... is it best to get genuine injectors or can you get reco's?... how much?? Cheers Some original photos have not been recovered yet.

Signs of leaky injectors in my experience are,engine popping & spitting when cold ,hard to start when warm or cold,excessive fuel consumption,poor response from idle,internally melted catalytic converter. I bought 6 second hand injectors for my VL about 3 years ago for $20 each as they were all leaking,only one failed 18 months ago (coil winding went in it) but otherwise I haven't had any problems. If you visit the inter - ject website they have a cause for this,things like ultra-sonic injector cleaning causes injector leakage and over a period of time magnetic particles from injector pintle wear causes microns of metal shavings to hold the pintle open,apparently they have a pulse generator which they attached to the injector terminals which reverses the polarity and demagnetises the pintle which in most cases can fix it. I coudn't be bothered & needed the car on the road so I just bought a whole second hand set,by the way,the first of the VN Commodores are renowned for it,one in ours went and their injectors use a metal disc rather than a pintle,the disc setup is prone to leakage.

G'day mate, I'm having the same problem, 4 of mine have crapped themselves, got some reco's for 120 each, and i believe it costs $22 each to get your injectors cleanned/crack tested. Cheers Scoota K