Holden Rodeo Engine Problems

We are told there can be problems integrating LPG systems on the Rodeo. Our advice is that with an early central point mixer type system the car’s ECU can be picking up an oxygen sensor signal that is at variance to the normal signal when running on petrol. Later injection systems don’t suffer from this problem. To sort that out you need to take your car to an LPG specialist. Also check the obvious, that your car is tuned correctly.

Everything has a statutory guarantee with it that covers the goods as sold. That you installed the engine yourself shouldn’t have any bearing on the guarantee, unless it can be shown that you have done something to cause the fault. In your case it would seem that is not the situation and the problem is with the engine as supplied by Holden.

There are a number of LPG systems available for diesels, but they’re different from those we’re used to on petrol engines. In the case of the diesel system an amount of LPG is substituted for diesel, the engine never runs on LPG alone, and the effect of that is to increase power. The idea is then that you back off the throttle and save on fuel, but some people make full use of the extra power and can suffer engine failures as a result. I would urge caution and certainly urge you to talk to other owners who have done the same conversion you are considering to get their experience. It’s also crucial to have an experienced installer do the work on your car.

Holden switched from the Isuzu 3.5-litre V6 to the locally produced 3.6-litre Alloytec V6 in 2006. The fuel economy was claimed to have improved by around 2.5 per cent in the switch.

Holden walked away from dual-fuel in the Rodeo after they fitted the Alloytec V6 engine because it was too complicated for them to fit the LPG-compatible engine on the production line in Thailand, but local converters have been doing the conversion without any problems. Have a reputable brand of LPG system fitted by a competent installer and you shouldn’t have any trouble.

It's odd that Holden's diagnostic equipment failed to find the problem oxygen sensors. In any case it is good to get an outcome, and it's something any other owner with a fuel consumption problem should think about checking.

Holden cancelled its LPG development program on the Alloytec engine in the Rodeo when it couldn’t make the valves and valve seats of the standard engine live long enough on gas. While Holden uses the Alloytec engine in its dual-fuel Commodore it’s fitted with hardened valve seats and valves in that car, but for reasons only known to Holden it couldn’t or wouldn’t fit the dual-fuel engine in the Rodeo. Talk to an LPG specialist about the conversion as some claim they can do it quite successfully, but approach it with caution.

THE Rodeo's V6 is the same Alloytec V6 that's used in the current Commodore. Holden offers a dual-fuel kit for the Alloytec V6 in the Commodore, but it has been modified for running LPG. Holden had been working on a similar installation for the Rodeo, but backed away from it because of difficulties having the LPG-compatible engine fitted in the Thailand plant where the Rodeo is built. It also checked to see if it could get away with running the standard V6 on LPG, but found problems quickly developed with the cylinder heads so never went ahead with the release of the kit. That was an injection kit being developed for Holden by Impco. Impco's advice at that time was that the Rodeo V6 was not suitable for gas, but the guys at the Australian LPG Warehouse have developed kits for it and claim they have fitted them to Rodeos and Commodores and have had no problems. The secret, they say, is they make sure the engine runs rich enough at wide open throttle on LPG so the combustion temperatures don't get high enough to cause problems with the valves and head.

IT'S A hard call. You'll be about $1500 out of pocket after you get the rebate, which means you need to add that to the price before you break even. When you do that, you're reducing your potential market of possible buyers. I think the Rodeo will appeal to a young tradie, and as such it may have more appeal as is with its lower selling price than it will if you fit it with LPG and increase the price. I would sell it as is and let the buyer decide to fit LPG.

EVEN though you're still shy of the mileage for the change, I'm sure you'll find you've exceeded the recommended time, having gone eight years without changing it. Having gone all that time you could probably get away with waiting for the 160,000km to roll around. Any mechanic can make the change. It's not necessary to go to a dealer.