Ford focus wagon 2002 undercarriage rattles when driving?

SOURCE: change rear signal bulb on 2002 ford focus wagon

Open the rear tailgate There are 2 screws that hold light housing in place.. Remove the screws then pull the housing outwards till the clip behind it springs. You then need to knock the housing sideways (outwards) to free the 2 prongs that attach housing to the car body.
Unclip the rear housing from the back of the light unit & change the bulb.

SOURCE: will a transmission for a 2002 ford focus fit a 2004 ford focus(both are sedans)?

if the numbers on the bottom of pan match .

SOURCE: fuel pump replacement on 2005 ford focus

Are you sure that you need to replace the pump? I drive a 54 plate mk2 1.6 zetec that wouldn't always start and I was told it was the fuel pump in the tank but because the fault was intermitant I didn't have it fitted and found out that the car didn't start because the fuel lift pump wasn't priming the system before starting. I found that there was a faulty connection on the relay for the pump that is in the compartment under the glove compartment.

SOURCE: Large piece of light weight metal hanging down

most likely a heat shield for the exhaust, may need to be reattatched

SOURCE: heat in 2001 ford focus wagon

first is there a moisture residue on inside of windshield if so heater core is shot. next the thermostat may be bad. what does your temp gauge read?