20 Most Recent 2003 Mercury Grand Marquis Questions & Answers

You don't need to rewire anything - driveablity problem . Do yourself a favor an take it to a qualified repair shop . All you'll do is make it unusable .

2003 Mercury... | Answered on Jan 26, 2019

Have you checked the transmission fluid level?

2003 Mercury... | Answered on Jan 14, 2019

It is not going into neutral. Your overdrive band is fried on your transmission. Typical problem on these transmissions. Transmission will need to be completely disassembled to get to the overdrive band. Complete overhaul. Recommended when you read the owners manual to not drive these uphill for long periods of time without shifting to regular drive.

2003 Mercury... | Answered on Oct 08, 2018

1. Simple answer...you may be low on antifreeze or water in the radiator. Add some to fill it up, and try again. DO NOT OPEN THE RADIATOR CAP HOT!!! Add to the overflow reservoir.

2. Check the manual lever is still moving the flapper/air blend door on your heater under the dash.

3. It could be worse, if the heater core is plugged.

2003 Mercury... | Answered on Oct 08, 2018

It is a simple but fiddly job. Examine where the arm rest hinges. There will be curved plastic covers. These should just pull up and off. It will reveal a silver pin with a black lock washer fitted on the end furthest from the door.
Using a pair of thin flat bladed screwdrivers and a LOT of patience, you should be able gradually lever the locking washer off the pin. If your careful you should be able to reuse the washer. Once the washer is off, the pin should tap out towards the door. The arm should lift up and out.
you might need to tilt the back of the seat to get better access.

2003 Mercury... | Answered on Jun 07, 2018

Sounds like the fuel filter

2003 Mercury... | Answered on Mar 01, 2018

The average person does not have pressure gauges or the specs for power steering pressure. These readings would show if the power steering pump pressure is correct and then pointing to the problem being inside the rack and pinion unit.

You may be able to take the pump into a hydraulic repair shop and have its performance taken. Although they may not know what rpm your pump needs to be turning for a given pressure performance.

Could be a procedure for air bleeding is special. There was a procedure for Ranger or Chevy S10 type trucks which had strange elevation requirements for fluid to be "burped" with hoses hung higher than pump case. Once air escaped higher elevated hose, system was primed.

Make sure of simple things, like fluid is correct type. Maybe some other Expert will supply more answers.

2003 Mercury... | Answered on Jan 17, 2018

  • Insufficient, erratic, or no heat
  • Low engine coolant level.
  • Engine overheating.
  • Plugged or partially plugged heater core (18476).
  • Temperature blend door binding/stuck.
  • Temperature blend door actuator (19E616).
  • Incorrect heater control valve (18495) operation.
  • Go To Pinpoint Test I .

Are the heater hose's going through the fire wall hot ?
I2 CHECK FOR HOT WATER TO THE HEATER CORE INLET HOSE WARNING: The heater core inlet hose will become too hot to handle and may cause serious burns if the system is working correctly. Allow the engine to reach normal operating temperature. Feel the heater core inlet hose.
  • Is the heater core inlet hose too hot to handle?
Yes GO to I4 .

No REFER to Section 303-03 to check cooling system function.

2003 Mercury... | Answered on Jan 06, 2018

This vehicle does NOT use a heater control valve. Coolant flows to the heater core at all times. Temperature is regulated by the blend air door and blend door actuator. Locate the blend door. Remove the actuator and open the door by hand. If you get heat, the actuator or the control head is bad. FWIW, the actuator is the most likely cause

2003 Mercury... | Answered on Jan 06, 2018

Under the car. You need a tool and you need to release pressure before changing.

2003 Mercury... | Answered on Dec 06, 2017

check the back of the radio, make sure than the antenna, connector is plug into the radio, if it is, then replace the radio.

2003 Mercury... | Answered on Aug 22, 2017

Check the fusible wiring link near the battery and fuse box. Sounds like it has burnt.

2003 Mercury... | Answered on May 22, 2017

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