Holden Problems

A problem like this could be caused by any number of things, James. Electronically interrogating the on-board computer is a wise first step, as the error codes that will result will possibly lead you straight to the offending component.

In cars like yours with electronic fuel-injection and engine management, there’s an array of sensors that need to send the correct signal to the car’s on-bord brain for everything to function properly. Replacing these sensors one by one until you fix the problem is a very time and cash consuming way of proceeding. Have the car scanned instead and see what fault codes show up.

Meantime, if I had to venture a guess, I’s say the problem sounds ignition related. An engine will often idle properly with no load on it, but when you select a gear, there’s suddenly load applied and, if the ignition system is not spot on, the engine can suddenly do all sorts of crazy things, including dropping cylinders. The other thing that occurs to me is that your battery might be low on charge. Injected engines absolutely do not like a lack of volts.

Since both variants of Colorado here use essentially the same engine, I’m not sure what sensors would be different and require changing. That said, the MY17 Colorado got recalibrated hill-descent and hill-start functions, so maybe there are some differences there.

The major mechanical difference that I can see between a 2014 and a 2017 Colorado is probably the power-steering. In late 2016, the vehicle switched to an electrically-assisted system in place of the previous hydraulic set-up. So the later engine would probably lack the pulleys and mounting hardware for the hydraulic power-steering pump that your vehicle requires. Perhaps they can be removed from the old engine and fitted to the later one.

Perhaps an easier solution would be to return the engine originally supplied and ask for the correct version for your car. If the engine supplied originally was not fit for purpose, then you’ve every right to ask for a replacement unit that is.

I think there’s a bit of confusion sneaking in here. Your Calais doesn’t have a timing belt, its engine is fitted with a timing chain instead. However, if it’s a V6 engine, then there’s every chance the timing chain does need to be replaced.

This seems counter to conventional wisdom where a timing chain should last the entire life of the car. But in the case of the particular V6 we’re talking about, the chain was definitely a weak point and lots of Calais and Commodores have needed replacement chains. That was particularly true if the engine received less routine maintenance than the handbook stipulated.

The first sign can be a rattle when the engine is started; sometimes you’ll get a check-engine light on the dashboard because the chain has stretched sufficiently to allow the camshafts and the crankshaft to become out of phase with each other. Either way, it’s new-chain time and you can expect to pay something like $2000 to have the job done, possibly more.

Most workshops will be able to carry out this work and, when it comes to finding a local garage, word of mouth from friends and family is usually a good way to proceed.

If you’re referring to the little light in the shape of an engine, or a `check-engine’ light, then you have at least one problem that the computer is identifying and warning you about. It’s the vehicle’s way of letting you know that something needs to be attended to.

But what exactly? Well, the best way to find out what’s wrong is to have the vehicle scanned electronically, at which point the computer should give up all the car’s dirty little secrets. Sometimes the fix will be very simple, at other times it can be a result of a major system failures. Either way, it needs to be checked before the damage becomes more extensive and/or the car becomes unroadworthy.

These late Commodores (the very last of the locally-made Commodores, actually) do, in fact, have a history of fuel injector problems. Holden has claimed that poor quality fuel is the cause, but some technicians disagree, arguing that it’s a problem inherent in the injector’s design. Some owners have been told that it’s better to run these cars on 95 or 98-octane fuel, even though the LS3 V8 is rated to run on 91-octane ULP. But it seems even cars that have been run on the pricier brew are still recording problems with the injectors.

The faulty injectors send the engine into a potential lean-mixture situation, at which point the on-board computer intervenes and sends the car into limp-home mode to avoid engine damage. That’s why you’re seeing all those warning lights on the dashboard, while the injectors themselves are what’s causing the rough running you’ve reported.

There’s been no recall on Holden’s part, but the word on the street is that a Holden dealer will replace the injectors free of charge if you present the car at the dealership with the symptoms in evidence. Holden’s announcement that it will cease to trade in Australia should not affect this situation.

It sounds like the entire car is shutting down. And if that happens at speed, or just as you’re preparing to pull out into moving traffic, that’s an incredibly dangerous thing to be happening. The best advice is to have the car scanned electronically, at which point the real problem might raise its head.

Beyond that, you’re clutching at straws, because whatever is going on is a fairly serious problem. Scanning the on-board computer doesn’t take long, and diagnosing the problem this way will save you time and money in the long run. It might even save you from a crash.

It sounds awfully like your car’s body computer is at fault here, Leslie. The body computer is the brain that talks to the keys and then commands the doors to unlock and the immobiliser to disarm so the engine can start. This unit also controls things like the power windows, interior lighting, and even the intermittent windscreen wipers. It also talks to the engine control module, and without that conversation happening properly, the engine won’t start. The problem is that the body computer can develop faults with some of these functions while others work perfectly, making diagnosis even trickier.

If it is on the blink, a faulty body computer can have all sorts of effects including doors that won’t lock or unlock, and can even cause the doors to lock momentarily before magically unlocking again the minute your back is turned.

I have also heard of keys becoming worn out with age and use, and if the car requires the key to be in very close proximity to unlock doors, the key could be at fault, too. The other possibility is that an aftermarket alarm system is interfering with the car’s standard functions.

Car alarms have a really bad habit of draining batteries. Aftermarket ones are the worst, but even the factory alarm can cause a run of flat batteries if it’s not working properly. The faster flashing red light on your dashboard is the clue that something has altered in the alarm or its settings.

An auto electrician can be your best friend in these cases. By the way, not all scanners are created equal and some of the cheaper, online versions don’t cover all the functions of a modern car. A Holden workshop will have the proper scanning tools to make a coherent diagnosis.