Two problems related to engine have been reported for the 2004 Volvo S40. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2004 Volvo S40 based on all problems reported for the 2004 S40.
The engine dies intermittently once every six months. This normally happens when making a right turn or slowing down. All of the warning lights in the dashboard light up. The gear must be put back in park, must turn off the ignition and then re-start again. The first time it happened, I thought it might have been a fluke, the second time I took it in they changed a valve in the engine, the third time they kept the car for 2 weeks and they changed the air compressor and positive/negative battery cables (they had a Volvo of north America technician come down). The last time it happened was Friday, August 19, 2005. I've called the dealership and they don't seem to want to take my call.
Multiple failures. Air bag system, problem starting and noise in steering. The vehicle also had an air condition problem. The air bag light illuminated on 3 occasions. The consumer stated the passenger seat was equipped with a device that weighed passengers to determine if the air bag should be activated.