Problems with 98 Expedition

[Rob]

Hello all,

I am having a couple of problems with my 1998 Ford Expedition XLT 5.4L 2wd automatic 98000mi.

1. When the vehicle reaches 80mph or downshifts up a hill my headlights dim significantly. In between 75 and 80mph the lights flicker. I had the alternator and battery replaced about 6 months ago but have only had this problem for about 2 months. Any suggestions??

2. My A/C compressor siezed (again) and I would like to replace it myself. I had it replaced by the dealer under warranty a year ago and of course, the warranty has expired. I don't have the 1400 to 2000 bucks to have it done by a mechanic. I understand that there is a lot of labor involved but I believe I can handle it. I guess I am wondering if this is doable or should I absolutely take it to a pro.

3. Finally, my heater is just blowing cold air until I drive it for about 30 minutes, then there is an odd smell and the heater will start working. I was told by a mechanic that it may be a blend door as both heater hoses were hot. What do ya think??

I really dig this truck so any help would be appreciated.

Sorry for the long post.

Rob

[DanD]

#1- I would have the alternator checked again, when it shifts the engine RPM drops and in turn the alternator will turn slower.
By chance do the lights dim at Idle?
#2 I can’t see why the compressor would cost so much, you can buy rebuilt units for 3 or 4 hundred and the flat rate book only pays 1.1 hours to do it.
As for doing it yourself, you would need the proper equipment to discharge and recycle the refrigerant along with system specifications to properly recharge it.
#3 I would start with a new thermostat a broken blend door doesn’t get better after driving 30 minutes.
Is the cooling system full?
As for the smell before you get heat I’m not sure, I guess it could be the blend door motor getting hot because of the door being jammed.
Way2old is the ford man, he’ll have some ideas on this.
Dan.

[way2old]

1. I would have the belt tensioner looked at also. If the tensioner is weak, it will allow the belt to slip and possibly cause this. Have the charging system checked again as Dand suggested. We had a long run of Ford alternators that were not any good. We may replace 3 or 4 on a one vehicle to get one that worked properly.

2. Are you sure it is the compressor or just the clutch and coil assembly? Either way it is not a really difficult job. If it is just the coil and clutch, you do not have to discharge the system to change. If it is the compressor, it needs to be properly discharged and evacuated to properly work.

3. I have to agree with Dand on this also. Replace the thermostat first to see if it cures the problem. If it is the blend door, more than likelyt it is the actuator that is your problem. With the key in run position, doors closed to keep dinging noises down, move the heat control from hot to cold to see if you hear a little electric motor running. If the motor runs, the actuator is OK. If you can not hear it running, more than likely the actuator motor is bad.

Here is a print out from the manual to help. Can't get pictures to come with it though.

SECTION 412-04: Control Components 1998 Expedition/Navigator Workshop Manual
REMOVAL AND INSTALLATION Procedure revision date: 07/09/2002

--------------------------------------------------------------------------------

Temperature Blend Door Actuator
Removal

All vehicles


WARNING: To avoid accidental deployment and possible personal injury, the backup power supply must be depleted before repairing or replacing any front or side air bag supplemental restraint (SRS) components and before servicing, replacing, adjusting or striking components near the front or side air bag sensors, such as doors, instrument panel, console, door latches, strikers, seats and hood latches.

To deplete the backup power supply energy, disconnect the battery ground cable and wait at least one minute. Be sure to disconnect auxiliary batteries and power supplies (if equipped).

Disconnect the battery ground cable and wait at least one minute. For additional information, refer to Section 414-01.
Vehicles equipped with floor console


Remove the floor console. For additional information, refer to Section 501-12.
All vehicles


Remove the floor duct panel.
Remove the pin-type retainers and release the expander clip.

Remove the RH instrument panel brake.
Remove the nut.
Remove the bolt.
Remove the brace.

Remove the LH instrument panel lower nut and position the brace aside.

Disconnect the restraints control module (RCM) electrical connector.

Remove the RCM and bracket assembly.
Remove the bracket retaining bolts.
Remove the RCM and bracket assembly.

Vehicles equipped with rear airflow duct


Cut the rear seat airflow duct along both sides.
Fold back carpet.
Cut rear seat airflow duct.

Fold the air duct rearwards.

All vehicles


Remove the floor duct.
Remove the two screws (one each side).
Remove the floor duct.

Remove the electronic blend door actuator.
Disconnect the connector.
Remove the screws.
Pull down to release the actuator shaft and remove the electronic blend door actuator.

Installation

All vehicles


Install the electronic blend door actuator.
Connect the actuator shaft.
Install the screws.
Connect the connector.

Install the floor duct.
Install the floor duct.
Install the two screws (one each side).

Vehicles equipped with rear airflow duct


Zip-tie the rear airflow duct to floor duct.

Reposition the carpet.
All vehicles


WARNING: The tightening torque of the restraints control module (RCM) retaining bolts is critical for correct system operation.

Install the RCM and bracket assembly.

Connect the restraints control module (RCM) electrical connector.

Install the LH instrument panel lower nut.

Install the RH instrument panel brace.
Install the brace.
Install the nut.
Install the bolt.

Install the floor duct panel.
Install the pin-type retainers and release the expander clip.

Vehicles equipped with floor console


Install the floor console. For additional information, refer to Section 501-12.
All vehicles


Connect the battery ground cable. For additional information, refer to Section 414-01


--------------------------------------------------------------------------------

[Robj]

Wow fellas, thanks for all of the info!!! I will definitely try to check it out this weekend. I will let you know how it goes. Again, thanks for the help.

Rob

[way2old]

No problem Rob. Hope your cures are simple for the Expy. Good luck.