Holden Problems

Many engines lose rpm when they are sitting at a hot idle. The problem could be with the fuel or ignition systems, but could also be a stepper motor that either needs to be replaced or reset (to re-establish the correct idle speed).

The oil light will be flickering because the sensor is telling the computer that there’s not enough oil pressure being generated to lubricate the engine properly. In turn, that’s because hot oil is thinner than thick oil (which means less oil pressure) and the amount of oil pressure generated is directly linked to how fast the engine is running. Hot (thin) oil plus a slow idle, means a dangerous fall in oil pressure.

If the oil pressure light goes out when you rev the engine a little, it will probably be okay, but don’t drive it like that for too long. Once the idle speed is reset, the oil light should not flicker on again. If it does, change the engine oil to a thicker (higher viscosity) specification.

There could be a complex, electronic, fuel-supply or engine-management reason for this, and if that's the case, having the vehicle scanned would be a good place to start. Or, it could be a case of human behaviour that is skewing your fuel economy figures.

By which, I mean that when you got the car brand-new, you gave it the kid-gloves treatment, understanding that the brand-new engine needed to be run in and would appreciate a slightly easier start to life. Then, as the novelty wore off and the vehicle began to earn its living, you subconsciously grew a heavier right foot. And it is this that's seen the fuel consumption creep up.

Failing that, you might have an on-board computer that has been silently recalibrating itself, perhaps in conjunction with software updates at the dealership which you may, or may not have, been made aware by the dealer. To be perfectly honest, I'd find 6.4-litre per 100km average on a Colorado borderline unbelievable, and the sort of economy only a dedicated fuel-saving driver could even get close to. Ten litres per 100km, meanw

It all depends on what you mean by coming on and off. The air-bag light should come on briefly every time you start the engine, but should then go out after a few seconds. This just confirms the car is checking the air-bag system for proper operation and is perfectly normal.

If, however, the air-bag light is lighting up randomly as you drive down the road, then you need to have the car scanned to see what the problem is. In this case it could easily suggest that there's a problem with this critical safety system, so don't ignore it.

No, the manual and automatic versions of the Crewman are rated to tow up to 1600kg and 2500kg respectively with a braked trailer. This is to protect the clutch of the manual versions which could easily be damaged trying to tow the automatic's 2500kg.

It's generally accepted that the more progressive take-up from rest of an automatic transmission makes it the better solution for a tow-car in the first place. And that extends beyond any single make or model.

The workshop you want is a specialist air-conditioning business. Air-con might have a simple job to do, but it’s a complex system with lots of interlocks to protect the various bit and pieces. If, for instance, the gas level is low, a sensor will detect this and disable the air-con compressor so the system can’t be damaged by running with low gas or lubricant. So, simply replacing sensors and other bits and pieces randomly is a great way to tear up money and still not fix the problem.

You need to have the system checked by somebody who understands the technology. They will test for leaks, check whether the system is holding pressure and then check the operation of the rest of the hardware including the compressor, receiver-drier, condenser, blower-fan and relevant filters.

If you’re lucky, the system may just need re-gassing, but you could also be up for some expensive new parts if there’s other damage or problems. But without a proper diagnosis, you’re flying blind.

On the surface, the two bootlids look very much alike. In shape, they may well be identical, but there's a catch. In 2012, Holden switched from the fully-imported Cruze to a locally built version of the same car. Which means that the two versions were painted in completely different factories (different countries, in fact) and the chances of two blues or reds or even whites colour-matching exactly are pretty slim.

If you look at the locally made Cruze line-up, you'll also see that many of the colours were shared with the Holden Commodore range (built in the same factory). The other thing to consider is that the paint on these cars was never stellar quality, and a decade or so of varying UV radiation exposure might mean that even two bootlids that started out the same colour, may not be now.

Compare the two bootlids in strong sunlight to gauge whether the colours actually match before committing to the swap. That said, if you do manage to match two bootlids in an identical colour, it will be a lot cheaper than having one resprayed.

Even though the Holden brand isn't selling new cars any longer, the brand still exists to service Holdens already on the road in Australia. Spare parts for an Astra are no problem to get hold of, either through a Holden service centre or from any number of suppliers, many of whom have websites you can look up.

That said, I wouldn't be too picky about having a 2018 car serviced by Holden, as any good workshop should be able to tackle any job on this relatively conventional car. But, if you do wish to use a Holden service centre, there are nine listed in the Perth area, so finding one shouldn't be a problem.

First thoughts are that the stepper-motor (which controls the idle speed) is faulty. That would explain both the high idle at low engine temps and the stalling and stumbling as you roll to a stop. This component is really just a small electric motor and shouldn't be too expensive to replace.

But have the car scanned first to make sure there are no other obvious causes for this behaviour. A faulty engine temperature sensor or some other small component could also produce these symptoms.

If the car in question has the 1.8-litre engine, then this is definitely a known problem. Plenty of these engines suffered cracked cylinder heads which could allow the engine's oil and coolant to mix, producing the symptoms you saw. Holden actually issued a service program to replace the cylinder heads and other components to address the problem.

The other major cause of these symptoms is a failure of the transmission's cooling system. This actually piggy-backs on to the engine's cooling system (they use the same radiator) but if the transmission cooler fails, it can allow transmission fluid into the radiator and coolant into the transmission. Eventually, this will destroy the transmission both mechanically and electronically.

In many cases, this (usually) four-digit security code will be written down somewhere inside the owner's manual or the car's service manual. Both these documents should be stored in the glovebox. Another popular way to store the code was to write it on the back of the business card of the salesperson who sold the car new, and attach that to the owner's handbook somewhere.

Often, however, these books go AWOL, at which point you need to contact a Holden workshop with the car's VIN. From there, you should be able to check Holden's records and find the security code. You may have to provide proof of ownership of the vehicle, however.

If that fails, sometimes you can do an internet search on a specialist website, but to do that, you'll need to know the serial number of the stereo unit. Usually, that involves removing the unit from the car, a process that can range from very easy to incredibly difficult.