2006 WQ Fiesta overheating problem

partychef · 15-01-2016, 08:20 PM

Hi all

My wife has an '06 WQ Fiesta, purchased over a year ago.

A few months back the car was overheating, after looking around we found a crack in the coolant expansion tank. We got a new tank and installed it with no more issues.

For the last month or so the vehicle has been overheating again. It doesn't happen all the time, I could be driving to work on the highway with air-con on but when I come to a stop or slow down in traffic, the temperature gauge starts to creep up.

I have played around with a whole heap of different scenarios and it all seems to come down to using the air conditioner.

I have done a radiator flush

I have a checked the oil and there is no milky deposits indicating coolant in the oil, the coolant doesn't appear to have any oil in it either.

The radiator fan works fine, I think (it does come on when the temp starts creeping up but doest seem to make a difference)

I have tested the radiator fan by disconnecting the temp sender. When this is done the fan comes on

I have replaced the thermostat

I don't think I'm losing any coolant but when the car is running the coolant can go from maximum to minimum and once I turn the car off the coolant will start flowing through the top overflow hose back into the expansion tank

Most of the time when I start the engine and start accelerating I can hear what sounds like water gushing from the firewall on the passenger side, the floor is not wet. It sounds like it's going through a hose

When it does overheat, the top radiator hose is hot and the bottom one is cool

Any help would be much appreciated

JVC063 · 16-01-2016, 08:02 AM

1. Do the fans come on as soon as the air con is switched on.
2. Sounds like the system needs bleeding

GTLEGEND · 16-01-2016, 10:15 AM

Make sure you have bled the system properly! To Bleed System, follow below taken from the WQ Work Shop Manual:

For 1.3/1.4 or 1.6L..

Filling and Bleeding
1. Remove the radiator bleed plug (if equipped).

2. Fill the coolant expansion tank until coolant
is expelled from the radiator bleed point or
stabilizes at the MAX mark (whichever occurs
first).
3. Install the radiator bleed plug (if equipped).
4. Fill the coolant expansion tank to the MAX
mark (if necessary).

5. Start and run the engine at 3000 revolutions
per minute (RPM) for two minutes.
6. Fill the coolant expansion tank completely.
7. Install the coolant expansion tank cap.
8. Start and run the engine at 3000 RPM for
another two minutes.
9.Switch Engine Off

For the 2.0L
Filling and Bleeding
1. Fill the coolant expansion tank to the MAX
mark.
2. NOTE: Do not allow the engine to reach
normal operating temperature.
Start the engine, run the engine briefly at
2500 revolutions per minute (RPM) for 10
seconds to prime the heater circuit.
3. Switch the engine off.
4. Fill the coolant expansion tank 15 mm over
the MAX mark.
5. Install the coolant expansion tank cap.
6. Start the engine, maintain the engine speed
at 2500 RPM for eight minutes or until the
engine reaches normal operating
temperature.
7. Maintain the engine speed at 2500 RPM for
three minutes after the engine has reached
normal operating temperature.
8. Increase the engine speed to 4000 RPM for
five seconds.
9. Decrease the engine speed to 2500 RPM for
three minutes.
10. Increase the engine speed to 4000 RPM for
five seconds.
11. Decrease the engine speed to 2500 RPM
for three minutes.
12. Switch the engine off.
13. Check the cooling system for leaks.
14. Allow the engine to cool.
15. Fill the coolant expansion tank to the MAX
mark.

partychef · 16-01-2016, 11:38 PM

Quote:

Originally Posted by JVC063

1. Do the fans come on as soon as the air con is switched on.
2. Sounds like the system needs bleeding

Yes fan does come on when I start air con but within a minute the temp gauge is rising.

I have bled the cooling system.

It all seems to revolve around the air conditioning. Could it be the radiator?

partychef · 16-01-2016, 11:41 PM

Quote:

Originally Posted by GTLEGEND

Make sure you have bled the system properly! To Bleed System, follow below taken from the WQ Work Shop Manual:

For 1.3/1.4 or 1.6L..

Filling and Bleeding
1. Remove the radiator bleed plug (if equipped).

2. Fill the coolant expansion tank until coolant
is expelled from the radiator bleed point or
stabilizes at the MAX mark (whichever occurs
first).
3. Install the radiator bleed plug (if equipped).
4. Fill the coolant expansion tank to the MAX
mark (if necessary).

5. Start and run the engine at 3000 revolutions
per minute (RPM) for two minutes.
6. Fill the coolant expansion tank completely.
7. Install the coolant expansion tank cap.
8. Start and run the engine at 3000 RPM for
another two minutes.
9.Switch Engine Off

For the 2.0L
Filling and Bleeding
1. Fill the coolant expansion tank to the MAX
mark.
2. NOTE: Do not allow the engine to reach
normal operating temperature.
Start the engine, run the engine briefly at
2500 revolutions per minute (RPM) for 10
seconds to prime the heater circuit.
3. Switch the engine off.
4. Fill the coolant expansion tank 15 mm over
the MAX mark.
5. Install the coolant expansion tank cap.
6. Start the engine, maintain the engine speed
at 2500 RPM for eight minutes or until the
engine reaches normal operating
temperature.
7. Maintain the engine speed at 2500 RPM for
three minutes after the engine has reached
normal operating temperature.
8. Increase the engine speed to 4000 RPM for
five seconds.
9. Decrease the engine speed to 2500 RPM for
three minutes.
10. Increase the engine speed to 4000 RPM for
five seconds.
11. Decrease the engine speed to 2500 RPM
for three minutes.
12. Switch the engine off.
13. Check the cooling system for leaks.
14. Allow the engine to cool.
15. Fill the coolant expansion tank to the MAX
mark.

Yep done that, no luck

partychef · 18-01-2016, 08:35 AM

Sooooo, while tinkering with it yesterday I had another look at the dipstick and oil fill port (been checking it regularly with no issue). Unfortunately yesterday there was milky oil present.

So I have a mechanic mate who will put if back together, I just need to get it to the point where it's cleaned and ready to go.

Obviously there is the underlying issue that caused the overheating in the first place. This may be the old coolant expansion tank, it may not... I took off the water pump and that seems like the bearings have started to fail. There is a small hole built into the outside of the casing that goes into the bearings area. It appears coolant has been leaking through there.

I guess I'll see how I go....

DZFord · 18-01-2016, 12:00 PM

Have you done a compression check on all cylinders? I'd hate to say it but it could be the head gasket. A small head gasket leak can cause combustion gases to enter the cooling system, causing gas pockets that may intermittently prevent proper circulation of your coolant, causing an intermittent overheating problem. Not to mention the milky oil being the other obvious sign.

partychef · 18-01-2016, 06:44 PM

Quote:

Originally Posted by DZFord

Have you done a compression check on all cylinders? I'd hate to say it but it could be the head gasket. A small head gasket leak can cause combustion gases to enter the cooling system, causing gas pockets that may intermittently prevent proper circulation of your coolant, causing an intermittent overheating problem. Not to mention the milky oil being the other obvious sign.

I left out that minor detail (a bit fatigued at the moment ) yes, I have accepted the fact that the head gasket is shot

xurbanx · 19-01-2016, 02:02 PM

Going to sound like a total novice. Perhaps there's a bubble in the coolant hose?
My WP had heaps of overheating problems - I ended up changing the radiator, hoses, thermostat, sealed the water pump (that was eventually replaced as well) only for the cause to be a bubble.