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The paper outlines and discusses the possibilities of a new instrumentation tool for the analysis of engine and gearbox noise radiation and the prediction of pass-by noise from powertrain test cell measurements. Based on a 32 channel data acquisition board, the system is intended to be quick and easy to apply in order to support engineers during their daily work in the test cell. The pass-by prediction is a purely experimental approach with test cell recordings being weighted by measured transfer functions (from the powertrain compartment to the pass-by point).

Volvo Truck Corporation has developed a new cold-start method for heavy duty engines. The background for this new method is to get a high cold-start quality, at a low product cost for the customer. This paper describes the development of the new cold-start method, the layout for the system and the start procedure in low ambient temperature. The basic element for this start principle is to increase the temperature in the combustion chamber before the combustion begins. The tools for achieving higher temperature are the following: Precranking a number of revolutions without fuel injection. Produce a back-pressure in the exhaust pipe to reduce the gas exchange and decrease the loss of heat in the combustion chamber. Volvo Truck Corporation uses the new cold-start method in production of the D12 engine.

For commercial vehicles the availability of the truck has become increasingly important to the owner. Unexpected stops and visits to workshops are expensive nuisances not least if caused by some minor faults. The cab comfort and the vehicle response are fundamental to the driver. The accessibility and fault localizing are principal to the mechanic. The safety and the environmental impact are scrutinized by the authorities. The adaptability are vital to the dealers. The climate capability is needed to global presence and to long distance transports. Light weight structural solution permits heavy pay-loads. Low total usage cost is a must to be competitive. Advanced technology is implemented into the truck at increasing rate to satisfy all the aspects above. Quality has become the key issue to reach for the high standard demanded.

Experience front nearly six years in production of air-to-air (A-A) charge air cooling (CAC) is reported. Solutions to overcome the drawbacks of air-to-air compared to water-to-air charge air cooling are presented.

Particulate-bound hydrocarbons emitted by diesel engines have been analysed using a rapid new technique. The method involves directly loading filter-borne particulate into a modified injection port of a gas chromatograph. Hydrocarbons are vaporized in this solid sample injection system and subsequently become adsorbed on to a chromatography column. The merits of this procedure are demonstrated by comparing results with those obtained using conventional gas chromatography (with liquid injection) and thermogravimetry. The contribution of unburned engine oil to diesel particulate emissions has been investigated using the new method. For a DI truck diesel engine operated over the U.S. Federal Heavy Duty Transient Cycle it is shown that 40% of the particulate appears to be derived from unburned oil. For a comparable IDI truck diesel engine this value was 28%.

The paper presents the development and experiences of the multifuel TM101G engine. The standard TD101G engine, which is a turbocharged, direct injection engine with a displacement of 9.6 litres, was modified and equipped with two separate injection systems. Diesel fuel was used to ignite the alcohol. Performance and endurance tests were carried out, together with emission measurements. Twenty trucks and buses run on methanol or ethanol were involved in a field test. Fuel consumption and oil analyses were followed up.