Help

[Benzowner]

The car has gone into limp mode, no warning lights are lit, but the temperature gauge is nearly into the red. I was given no warnings, just happened, anyone any ideas?

 

[pammy]

Coolant?

 

[Brian WH]

As Pammy says, check for low water, low oil and leaks. If all OK then you need to get it on a Diagnostic check to see why.
It should reset when ccoled down anyway, by restarting the car.

 

[Benzowner]

Coolant?

Looks like If I don't know what was in there, can I just add a coolant to BS6580, MB Spec as its Sunday morning and MB aint open.

 

[Brian WH]

Looks like If I don't know what was in there, can I just add a coolant to BS6580, MB Spec as its Sunday morning and MB aint open.

Yes that should be OK, even pure water to get you going will do in this weather, till you can treat it for the longer term..

 

[Benzowner]

Bought 3 litres of coolant at local store and overfilled with 2 litres so probably only heeded about a litre and a bit. Drove the car again to check if all was ok, no coolant loss, engine went very close to red and into limp mode. I have now let the engine cool and checked the levels again, coolant is ok, engine oil is ok. All the fans work including the electric ones. If there is no warning lights, will diagnostics pick up if there is anythin wrong? I am a little stumped why it would overheat with full coolant levels.

 

[pammy]

Let the engine cool right down, then check the oil filler cap from your cylinder head to ensure that's clean and not emulsified. This has the sounds of head gasket trouble if all your levels are OK.

 

[glojo]

This may sound a silly question, but is the water actually being cooled, fans, belts etc

Check to see if there is hot air coming out of the heater?
Heaters need water to heat up.

John

 

[Benzowner]

I have checked the usual suspects for head gasket, not water in the oil, hard to see if there is any oil in the water, the oil filler cap is clean, no emulsification, the car has now been dtood for a couple of hours and the temperature gauge is still on 80 I would have thought it would have cooled by now.

 

[pammy]

Water pump?

 

[bren221]

Try the termostat could b stuck.

 

[Ian B Walker]

Try the termostat could b stuck.

Thats my guess too.

 

[Benzowner]

Would the top hose still get hot with a stuck thermostat? Mine is getting very hot, but that is how I would expect it. Thanks for all the advice tho, it keeps me checking all the time.

 

[glojo]

Are you getting hot air out of the heater???

This is a very simple way of knowing if water is actually circulating.

Apologies if you have already answered this question

John

 

[Satch]

Is this overheating constant or just when in traffic/not moving very fast?

 

[Benzowner]

Answeres to questions, The heater works fine in fact too fine in this hot weather I let the car cool all afternoon and just took it for a drive of about 2 miles. The temperature was at the red when I reversed into my drive so it is constant. The thermostat theory sounds good tho as the temperature gauge just steadilly climbed.

 

[w124coupe]

Don't forget a new gasket when you nip out for the thermostat!

Also worth a quick look to make sure someone didn't put a cheap hose on in the past - they can collapse flat or into a kink (!) when hot.

 

[Bazzle]

80 is normal temp. May get to 95 before fans come.

If it needed 1.5 litres it must of come out some where? Or you havnt checked level for a while.

Bazzle

 

[Dieselman]

Geof it definately sounds like the thermostat is stuck closed. The stat is on the return to the block from the radiator, hence the top hose feels hot, I bet the bottom one isn't.

Undo the housing and break out the centre of the stat as an emergency get you by.

 

[Benzowner]

Thanks for all the info guys, the car is in for investigation, hope it is only the stat, I will let you know, after all it is another bit of info for the memory should anyone else have similar problems. Again thanks all