Holden Problems

The fact that it’s running roughly once it’s warmed up suggests you have a problem with either the head gasket or the head, even though there’s apparently no oil in the coolant. Try and identify which cylinder, or cylinders, are misfiring and remove that head to check it.

Ignition coil failures have been an often reported failure on Commodores going back a number of models; it's not necessarily something new. I couldn't say the others will fail any time soon, after all the two failed coils did 184,000 km before giving up.

Good to know that the problem can be fixed, but I would think such a rework is beyond all but the most enthusiastic owners.

It’s a bit like comparing a carburetor with fuel-injection. A carburetor is really a compromise and is very difficult to tune perfectly for all running conditions, so there is often a problem where the engine coughs, splutters, misfires, stalls or surges. Electronically-controlled fuel-injection can be more precisely tuned to all running conditions, whether it’s hot, cold, wet, windy, high speed, low speed, whatever. The end result is that the car performs better and gives better economy. It’s the same with the vapour-injection system; your car will run better, it won’t stall, stumble, surge, and the performance will be the same as it would be on petrol. Whether that makes it worth the extra $1900 or so it would cost is only a question you could answer. For me it is, I wouldn’t be bothered with an old air-valves system, which is the cheaper system you would be getting.

I'm told that the analog AM signals being transmitted at the moment are not the best quality, stations are concentrating more on the digital signals and neglecting the analog signals that will disappear, which might explain your problems. We're also told that a reception problem should affect all stations, not just one as you suggest, and our radio expert is at a loss to explain why the interference might be worse when the brakes are applied. Perhaps take it to your local radio specialist and have them check it out for you.

Using power steering fluid instead of brake fluid is probably the reason the brake pedal went to the floor and you lost all braking. You need to have the brake system flushed and filled with new brake fluid. It also sounds like you should have the car checked to investigate why the ABS light is coming on.

No, I wouldn't waste my money on doing it, it would handle one tonne without a problem. Sure, the weight of the trailer will mean the rear suspension will ride lower and that will increase the tyre wear a little, but I don't believe that's enough to justify the expense of upgrading your suspension.

The 186S motor was a sporty six introduced in the HR model and continued in the HK, HT and HG models. It replaced the X2 twin-carb motor in June 1967, and had revised inlet and exhaust manifolds and a modified air cleaner. Peak power was 108 kW at 4600 revs and maximum torque was 249 Nm at 2200 revs. It's not a super rare engine.

Sometimes, when a car sits for an extended period of time, the oil can drain back down into the sump from the top of the engine. If that happens it can take a few seconds for the oil to be pumped back up to the top again, and in that time the lifters can rattle. I would guess that’s what it is, but if you are concerned about it have a mechanic check it.

The guys at the LPG Warehouse have just fitted an EMER vapour-injection system to a similar car to yours and it’s working a treat for the owner. In that installation they used a toroidal LPG tank and removed the spare wheel; the owner was happy to keep his boot space and use a puncture repair kit should he encounter a flat tyre. They can also use a smaller cylindrical LPG tank if you wanted to retain your spare. Contact the LPG Warehouse on 03 9770 2287 for more info.