Weird auto box & temp gauge behavior

Hi.

Yesterday I experienced a new and rather odd problem.

After about an hour of driving quite free flowing traffic, as I slowed to a halt, the auto box didn't want to change down and I had to press the brake pedal harder to keep it still. I moved the selector to neutral and it jerked out of gear and was a bit jerky when I moved off again.

At the same time as this occurs, the temperature gauge stops working. A little later the temperature gauge started working again and the auto box also worked normally. Then it repeated the whole routine again increasingly regularly.

When I parked up, it all felt very hot but the fan which would normally still be running for a while, was not doing anything though it had been quite noisy while still driving. The coolant expansion bottle was almost empty but as it cooled it re-filled to between the max and min marks.

When I returned home doing the exact same route and taking roughly the same time, I no problems at all.

Any ideas as to what may be the cause of this problem would be gratefully received.

Many thanks.
Gareth.

Head Gasket
Thermostat
plastic coolant pipe leak
cracked coolant header tank

More information needed please.
What mileage is on the car?
How often do you check or top up the coolant?
When was the thermostat last changed?
When was the box fluid last changed?
Does the engine idle at 750 rpm when hot?
Was the MIL on or F4 displayed on the dash?

thanks for the comments so far.

The answers to the questions are:
What mileage is on the car? 109,000 miles
How often do you check or top up the coolant? Every 6 months or so or when the garage does it.
When was the thermostat last changed? 06/11/2013 also plastic coolant pipes at the same time.
When was the box fluid last changed? 05/07/2014
Does the engine idle at 750 rpm when hot? Yes
Was the MIL on or F4 displayed on the dash? MIL

Coolant header tank looks OK.

Worried about head gaskets now !!

Is the coolant the same colour as you put in or has it changed colour?

It's still the same sort of pink it was when it was put in, and still clear, not opaque.

Just a snippet of advice. The coolant level should be checked weekly. The reason for this is simple. The thermostat can leak, unseen as it's in the V. If the V6 coolant level drops by more than 1 litre or so, the head gaskets will fail. It's vital that the coolant in the expansion tank stays above minimum for this very reason. I check my coolant weekly, it's simply good practice to do so.

I don't think your fault is the HG though. The symptoms are wrong. I suspect a bad connection somewhere. First check would be the gearbox barrel connections, these are prone to failure, producing all manor of odd faults in the process.

Look at the temp sender connections and the , as the gearbox needs to know if it is hot or cold so it can shift at the right time.........

Thanks folks.

Looks like checking gearbox barrel connections and temp sender connections are the way to go. The gearbox has been in and out recently so I suspect that is the culprit.

I'll also check my coolant level weekly from now on.

Check the wiring loom to/from the barrel connectors int damaged anorl.

OK, you are probably going to have a laugh about this but I have got under the front end of my V6 Freelander for the first time to try to locate the "gearbox barrel" and there's a big black plastic under tray with a number of round fasteners with small round holes in them. How the hell do you get the under tray off?

The plastic comes off along withe the aluminium bit ....

4 bolts at the front edge and 2 bolts either side at the back. It's kinda obvious when you know they come off as one piece..

Good luck!

There's no need to remove the under tray to get at the box barrel connections. They are visible from the top, clipped to the front a of the gearbox.

Thanks.

Now I know how to get the under tray off but don't need to anymore.

The next challenge is to take the engine cover off. The 2 screws at the front and the rubber strap at the back are easy enough, as it the hose clip on the single air hose on the left. The 2 on the right seem to be attached with something that looks as though it is for one use only and the smaller hoses below are held on with cable ties. Looks like I'm going to have to go and buy a selection of hose clips before I attempt this.

ZDomZ said:

The plastic comes off along withe the aluminium bit ....

4 bolts at the front edge and 2 bolts either side at the back. It's kinda obvious when you know they come off as one piece..

Good luck!

Click to expand...

My facelift has another 2, in front of the ones that attach to the bumper. Then there are the 2 self tappers either side...... of the bumper in front of the wheels.

Nodge68 said:

There's no need to remove the under tray to get at the box barrel connections. They are visible from the top, clipped to the front a of the gearbox.

Click to expand...

Oh joy of joys, I can see 2 barrel shaped electrical connectors without taking either the under tray or the engine cover off.

Are the things in the attached, the things I need to check?

gareth1011 said:

Oh joy of joys, I can see 2 barrel shaped electrical connectors without taking either the under tray or the engine cover off.

Are the things in the attached, the things I need to check?

Click to expand...

Yes those are the barrel connections.

gareth1011 said:

Thanks.

Now I know how to get the under tray off but don't need to anymore.

The next challenge is to take the engine cover off. The 2 screws at the front and the rubber strap at the back are easy enough, as it the hose clip on the single air hose on the left. The 2 on the right seem to be attached with something that looks as though it is for one use only and the smaller hoses below are held on with cable ties. Looks like I'm going to have to go and buy a selection of hose clips before I attempt this.

Click to expand...

Since I was "playing" with the barrels for couple of weeks, I can offer a bit of advice.

No need to remove the engine cover to get to the barrels. If you stand in front of the vehicle, look down on the right side of the engine, between the radiator, and the tranny block. You can follow the electrical harness down, and you will see two barrel connectors being held in the clip (unless the clips were broken, and the barrels are just danggling there).

They twist to open, and this you should do in order to clean them. Get a good contact cleaner, and spray insides (the pins and receiving sockets), and the outsides (where the wires go into the barrel). Do it GENEROUSLY, and in my case, it took FOUR cleanings to get it clean. I cleaned, reconnected, drove, fault kept coming back, then undo the barrels again, clean and repeat. It took a while.

The reason it happened is pretty obvious (if you think about it like I did, for several nights!). Barrels are treated with some kind of grease, when assembled. All is good, unless these are opened later in the lifetime of the vehicle. I had the whole powertrain replaced (engine and tranny as a unit). If you want to take the tranny out, you have to undo the barrels (obviously). When it's all reconnected, the grease (that became HARD and brittle over the years) is forced in between the pins and their sockets, and there is the interruption of the contact! Simple, but hard to find, especially if the loss of contact is intermittent (like it was in my case).

My problem was also compounded by the car being parked in the junkyard, with it's hood open, and the rain (plus grease, junk, dust, etc) falling on the fuse box. Cleaning ALL electrical contacts, ground points, fuse boxes, and connectors, restores the loss of communication.

This approach costs nothing (except the contact spray), and I would start there in ANY case of electrical problems. Once you are SURE that all is clean, and has a good contact, you can proceed to trace the fault, and repair/replace the components that might be faulty.

I took my wife's Hippo to SEVERAL very knowledgeable transmission/electric/computer specialists, and they were totally STUMPPED. With the help from the forum, and my own perseverance, it's all sorted out now, and I didn't have to replace ANYTHING! Just a good cleaning. The grease in the barrels is obviously very stubborn, and only on the FOURTH cleaning attempt, it worked. Unfortunatelly, there is NO WAY to see if you cleaned everything out, or not. I just kept cleaning and trying. IF the cleaning didn't work, I was ready to cut the barrels off, and solder the wires directly. Luckily it was not needed.

Hope this helps you.

Danielsand said:

Since I was "playing" with the barrels for couple of weeks, I can offer a bit of advice.
.
.
.
Hope this helps you.

Click to expand...

It sure does help. Thanks. The box has been changed so what you say may very well be the case here. First cleaning attempt underway.

The maladies have now been diagnosed as being down to exhaust gases getting into the coolant which sadly means head gasket or worse and it has been deemed beyond economic repair.

It still goes so I guess it's time to get rid of it before it gives up completely.

anyone want a V6 5 door Freelander?