The suspension system on the Lotus Carlton/Omega consists of a number of key components, namely springs, dampers and the leveling system. All are specific to the car and have few, if any shared components with the rest of the Carton/Omega-A range.
Front Suspension
The front suspension consists of a standard arrangement of MacPherson struts. Known concern areas are as follows:
Corroded spring cups - the spring cup washer can rust through causing a knocking from the front suspension, especially under cornering load.
Broken springs - a number of instances have occurred where the front coils springs have fractured.
Wishbone bushes - the lower wishbone bushes eventually wear out and cause premature tyre wear. The only resolution is to replace the wishbone itself.
Rear Suspension
The rear suspension set up is virtually the same set up as the Carlton GSi/Omega 3000 with the inclusion of an additional link. Although the set up is similar, the springs, dampers and bushes are different. Check the usual things that you would normally check with any car but when you test drive the car, check for knocking from the rear especially if the car breaks traction. This is normally an indication that the trailing arm bushes have failed.
Rear Suspension Leveling System
As part of the standard rear suspension set up, there is an electro-pneumatic leveling system. This is designed to maintain the pitch and geometry of the car regardless of speed and load. The system consists of a sensor (with a tie rod to a trailing arm), a pneumatic pump and pneumatic inflation of the shock absorbers. A straight forward test can be performed on the leveling system:
| i) | Switch the ignition to position 2 but do not start the engine (dash lights illuminated). |
| ii) | After anything up to 2 minutes, you should hear the
suspension pump activate (whirring from the back end), this will continue for a short
period of time to pump up the suspension. If the pump does not stop, the pneumatic system is leaking, either a pipe, joint or shock absorber. |
| iii) | Once the pump stops, measure from the ground to top of the rear bumper - the distance should be in the region of 630mm. The height can be adjusted from underneath. Pump each of the rear corners of the car and listen for hissing - pointing towards leaking shock absorbers. |
| iv) | Now sit in the boot, after up to 2 minutes, you should hear the pump activate to correct the ride height of the car. |
| v) | Get out of the boot and turn the ignition off, at some point you should hear the circuit evacuate. |
If the suspension leveling is not functioning, the geometry of the car will be incorrect which will cause severe wearing on the inside edges of the rear tyres.
One other thing to be aware of is the tie rod for the sensor itself. If this becomes unattached, the suspension will pump to full height and cause the rear end of the car to be exceedingly high which in turn will compromise the handling to the extent that an accident could be caused.