Holden Captiva Engine Problems

There’s a variety of ways a turbocharged engine can lose boost. You might have a problem with the intercooler or even something simple like a dirty air filter. Don’t rule out a fuel supply problem which is causing the computer to reduce boost to account for a lack of fuel.

But one thing that has been noted in these cars is a cracked or broken boost pipe. If that happens, the boost will be lost to the atmosphere before it can get to the engine. Black smoke from the exhaust is a common accompaniment to this problem.

Holden’s own service schedule for this model Captiva doesn’t specify a change interval for the differential oil. Instead, it recommends the oil be changed when required according to how the car is behaving. Which would suggest that your car is, indeed, ready for new differential oil.

As far as the scan goes, be sure not to confuse a sticking or non-engaging rear differential with the same behaviour from the centre differential. These are both technically differentials, but have vastly different roles to play. In the case of an electronically operated differential, the clutches can sometimes be replaced separately, but in any case, you need to go deep inside the differential, so while your mechanic is in there, have them check out the whole unit.

What you haven’t told me is whether your car is a petrol or diesel Captiva. The two engines have very different ways of operating and both can make very different noises depending on what’s going on with them.

Diesel engines often have a fair bit of fuel pump noise which can increase as the car travels more kilometres and the pump develops a bit of wear. But whichever engine we’re dealing with, if the noise is at idle, then you’d really want to check the engine’s oil pressure. Oil pressure is lowest at idle, and low oil pressure can cause noises from the hydraulic lifters and even the engine’s crankshaft and pistons. Neither of those are what you want to hear, though, as they suggests some fairly major internal wear or damage.

This is a very contentious issue and occurs when the car decides it’s in mortal danger if it’s driven any farther. In many cases a car will go into limp-home mode with reduced power to get you home without further damage, but in the Captiva’s case, it can go one step beyond limp-home mode and simply shut itself down, lock the driver out of the equation and refuse all attempts at being moved. This has severe ramifications if it does so on a level crossing, for instance.

In any case, this condition is usually triggered by a serious fault to do with the engine and can include a lack of oil or a severe overheating condition. When things cool down after a while, the car will sometimes restart, but in the meantime, it’s not going anywhere. The suspicion is that you have a major mechanical problem on your hands, and continuing to drive the car (when it decides to co-operate) puts you in danger of a catastrophic driveline failure.

As part of a car’s exhaust system, a catalytic converter contains some pretty exotic metals that help convert the engine’s exhaust gasses to less harmful chemicals. It’s pretty high-end chemistry, but the converter’s job is to make the overall exhaust emissions less harmful to people and the environment.

Several things can go wrong with a catalytic converter that can stop it doing this job, and that’s when the dashboard light will flash on, alerting you to the fact that the converter needs attention.

Sometimes, the converter’s internal structure (the matrix) will collapse, at which point the only solution is to replace the unit. But sometimes, the matrix simply gets clogged by soot and other contaminants from the engine’s combustion process. In the case of the latter, you can remove the converter and manually clean it or, add a chemical to the car’s fuel tank that will be burnt in the engine, pass through the converter and hopefully clean it.

However, the jury is still out on whether using either method to clean a catalytic converter is worth the time and effort. Many cleaning attempts have led to the dashboard light flickering back on within minutes of the cleaning taking place. Perhaps the additive method is worth a try, but in a high percentage of cases, converter replacement is the only fix. So why not just remove the converter? Because it’s illegal to tamper with a car’s emissions control devices and there are big fines for those who do so. Also, a catalytic-converter warning light on the dashboard is actually a roadworthy item.

When things like a car’s lights start to develop a mind of their own, the car’s body computer is sometimes the root cause. This is the computer that controls everything from the central locking to the lighting and the climate control to the cruise control, as well as a lot more in between. If this computer module starts playing up, all sorts of weird things can take place, including the dashboard lights coming on of their own doing. If this happens overnight or when the car is parked for a long period of time, it could easily drain the battery and leave you with no electrical power.

An auto electrician is the obvious solution, but try this trick at home first. Remove the negative battery terminal on the car and leave it disconnected for an hour or two (or, even better, overnight) this is sometimes enough to reboot that body computer and return the car to normal operation. Be aware though, that even if this fixes the problem, it may recur sometime down the track. But at least then you’ll know what to do next time.

Any remedy can only be suggested once you know what’s causing the problem. The first step, then, is to have the car scanned to see if there’s a problem the on-board computer has identified and logged. Once you have that information, you are a lot closer to knowing what to replace.

Logic suggests that an engine that runs roughly when it’s cold might be running lean. If that’s the case, it could be caused by many things including worn injectors, a lazy fuel pump or even a temperature sensor that is not telling the computer that controls these things that the coolant temperature is low and the engine needs more fuel to compensate. Then, once the engine has warmed up, the fuel-air mixture is correct and the engine settles down and runs properly. That said, 30km is a long time for the engine to take to warm up.

You could spend lots of time and money replacing the wrong bits here, so a scan is definitely the way to proceed.

There are lots of places for a car to lose its coolant. The cooling system is a network of pipes, water jackets and other plumbing that is required to keep the engine cool, provide heat for the cabin and even cool the transmission.

Obvious places for a leak to occur are any of the joints in this plumbing, the water pump itself or any of the various components that store the coolant (heater core, radiator, overflow tank). A failed welch plug will definitely cause a car to lose coolant, but it usually starts out as a small leak before developing into a bigger one as the plug deteriorates further over time.

If the water is really running out as fast as your pour it in, the best idea is to get somebody to add water to the radiator while you look in the engine bay and under the car with a torch. A leak as big as the one you describe should be very visible.

Many engine designs have the coolant temperature sensor screw into the thermostat housing. In the case of this model Captiva, however, the sensor screws into the inlet manifold next to (but not part of) the thermostat housing.

A temperature sensor that is sending the wrong information to the car's computer can cause all sorts of mayhem, but it's worth checking the sensor for correct operation before spending money on a replacement.

Depending on what sounds the engine is making will determine whether the engine is a throwaway or can be fixed. But if the consensus is that the engine in your car is beyond redemption, then I reckon a second-hand engine from a wrecked Captiva would be the best bet. I don’t think the car itself would be worth enough money to justify a rebuilt engine which could run to $10,000 or more.

Nobody wants to tell you this, but fundamentally, the Captiva was a pretty ordinary car. Lots of owners had lots of transmission problems (which you already know about) and plenty of diesel engines destroyed their turbochargers and – in some cases – the rest of the engine in the process. The petrol V6 was no beacon of excellence either, with a terrifying propensity to consume timing chains.

Who at Holden has rejected your claim for help in repairing the car? If it was the dealer, I’d simply go around that business and talk directly to Holden’s customer service department. The fact that the car has a full Holden service history might sway opinion at head office, but I wouldn’t be going to the bank on it given the age of the vehicle.