Methods and systems are provided for conducting an evaporative emissions test on a fuel system in a vehicle. In one example, in response to a determination, based on the prevailing vehicle and ambient thermal conditions, that altering vehicle height may increase pressure or vacuum build during a pressure or vacuum build phase of an engine off natural vacuum test, employing the vehicle's active suspension to make said height adjustments. In this way the accuracy of engine off natural vacuum testing can be improved, and the conditions under which such testing can be efficaciously conducted increased.

Methods and systems are provided for diagnosing a shock absorber coupled to a vehicle tire. In one example, a sensor of a tire pressure measurement system coupled inside a tire is used to measure a tire pressure as well as an oscillatory behavior of the tire. A state of health of a shock absorber coupled to the tire is estimated based on the oscillatory behavior.

An air suspension system is provided with air spring devices, a pressure accumulation tank, a compressor device that supplies compressed air at least to the pressure accumulation tank, and that includes an electric motor, a pump device, and a dryer, and a control device that performs a vehicle height increase control, a vehicle height decrease control, an air suction control, and a regeneration air discharge control. The control device performs a heat accumulation control, by actuating the pump device with the communication between the compressor device and the air spring devices being blocked, supplying the compressed air discharged through the dryer to the pump device to be circulated, and accumulating heat of compression of the compressed air in the dryer, to regenerate the dryer.

An object of the present invention is to obtain an electromagnetic suspension apparatus capable of meeting a request to improve ride comfort irrespective of a magnitude of a spring constant preset in a spring member. The electromagnetic suspension apparatus includes an electromagnetic actuator that generates a driving force related to vibration damping of the vehicle body, an information acquisition unit that acquires information on a stroke position of the electromagnetic actuator, and an ECU that calculates a target driving force of the electromagnetic actuator and controls a driving force of the electromagnetic actuator using the calculated target driving force. When the stroke position acquired by the information acquisition unit is in a neutral range including a neutral position, the ECU corrects the target driving force so as to reduce a spring force related to the spring member as compared with when the stroke position is in a non-neutral range.

A suspension system for a vehicle and method for operating the same includes a shock absorber housing having a longitudinal axis, a spring disposed around the shock absorber housing and a retainer collar disposed around the shock absorber housing. An actuator coupled to the retainer housing moves at least a portion of the retainer housing to move the spring in a direction corresponding the longitudinal axis.

Methods and systems are provided for enabling a vehicle for which a jet pump that functions to transfer fuel from a passive side to an active side of a saddle fuel tank is degraded, to reach a desired destination by the taking of mitigating action. The mitigating action includes conducting a driving maneuver in response to an indication that the jet pump is degraded, the driving maneuver conducted in order to transfer a desired amount of fuel from the passive side to the active side. In this way, a vehicle may reach a desired destination even under circumstances where the vehicle may otherwise be unable to reach the desired destination.

A suspension system for a vehicle and method for operating the same includes a shock absorber housing having a longitudinal axis, a spring disposed around the shock absorber housing, a retainer collar disposed around the shock absorber housing and an actuator engaged to the retainer collar. The actuator moves at least a portion of the retainer collar to move the spring in a direction corresponding the longitudinal axis. A switch generates a ride height position signal. A controller is coupled to the actuator and the switch. The controller controls a position of the actuator in response to the ride height position signal.

Vehicle ride can be improved using perception based suspension control on a vehicle. A computing system on the vehicle may receive a map of a road surface. The computing system may identify a trajectory of the vehicle relative to the road surface, and determine if a deformation exists in a track of one of the vehicle tires. The deformation may include a depression and/or a raised portion from the road surface. The computing system may calculate an adjustment to make to one or more suspension system components to negate or minimize the effects of the vehicle traveling over the deformation or roughness of the road, and may send an instruction to adjust the suspension components accordingly. Additionally, or alternatively, the computing system may determine that the deformation may be avoidable, in whole or in part, and may cause the vehicle to maneuver around the deformation.

Methods and systems are provided for diagnosing a shock absorber coupled to a vehicle tire. In one example, a sensor of a tire pressure measurement system coupled inside a tire is used to measure a tire pressure as well as an oscillatory behavior of the tire. A state of health of a shock absorber coupled to the tire is estimated based on the oscillatory behavior.

A vehicle-height control system is configured to control a vehicle height for a wheel. The vehicle-height control system includes: a vehicle-height control actuator provided so as to correspond to the wheel; a pressure-medium supply and discharge device configured to supply and discharge a pressure medium to and from the vehicle-height control actuator; and a vehicle height controller configured to control the vehicle height for the wheel by controlling the pressure-medium supply and discharge device based on an inside temperature and an outside-air temperature to control at least one of supply and discharge of the pressure medium to and from the vehicle-height control actuator. The inside temperature is a temperature in the vehicle-height control system.