Overheating, Hot top hose, cold bottom hose...ECT?

**1.9 TDI Sharan** · 23-04-2008,04:24 PM

Am still tracing an over heating problem.

After a 15 mile run, oil temps crept up to 112 deg, water temp gauge went up to 3/4...
Top radiator hose was hot, bottom was cold! Where is the thermostat?

Also what is and where is the ECT sensor?
TIA.

**shabazmo** · 23-04-2008,09:10 PM

Thermostat is at the end of the bottom radiator hose on the AFN 1.9 engine. Requires the removal of power stering belt, pump, and one or 2 brackets.

**Crasher** · 23-04-2008,09:12 PM

Which year, is it an AFN?

**1.9 TDI Sharan** · 23-04-2008,09:24 PM

Its a 99 AFN as far as Im aware...
Makes sense that its on the bottom hose as that was the cold one. Am thinking I have a stuck shut stat....

Any help with the ECT sensor? What and where?

OK so the ECT is the Engine Coolant Sensor, where is this located? Have a sensor in the middle of the top radiator hose and on the rright tower of the radiator bur=t not sure if either are what Im looking for.

**Crasher** · 24-04-2008,11:53 AM

Certainly sounds like the stat is staying shut. The CTS is on the end of the head in a black plastic housing over the gearbox.

**1.9 TDI Sharan** · 24-04-2008,06:06 PM

Originally Posted by Crasher

Certainly sounds like the stat is staying shut. The CTS is on the end of the head in a black plastic housing over the gearbox.

Thanks, will go out and have a look to see if I can find it.

**shabazmo** · 24-04-2008,06:46 PM

Sorry to ask a stupid question. What is a CTS or ECT? Thanks

**1.9 TDI Sharan** · 24-04-2008,08:24 PM

Originally Posted by shabazmo

Sorry to ask a stupid question. What is a CTS or ECT? Thanks

No such thing as a stupid question...
Same thing, CTS Coolant temp sensor, ECT Engine coolant Temperature sensor

**Crasher** · 24-04-2008,09:15 PM

Sorry, force of habit assuming people know what all the TLA's mean

**1.9 TDI Sharan** · 25-04-2008,07:22 PM

OK so I got the car up to temperature and shut her down. Waited a few seconds and then tried to start her. Engine cranked for 5 seconds before starting.

At this point top rad hose was hot, bottom was cold. Stat is surely knackered. Thinking about this it would obviously be the problem with the fans not running, no hot water is being circulated around the rad!!!

Shut her down again and disconnected the ECT/CTS and tried to start her...started with first flip of the key as if she were cold. Only difference being the revs went up to 1900rpm ish momentarily as if started with foot on accelerator. The ECT obviously also controls how long glow plugs are on for.

Will be replacing stat this weekend.

The ECT has 4 wires and I have been told this may be a dual sensor. One sending temp info to the ECU and one sending info to the temp gauge. Is this correct and if so is it likely that one of these has gone faulty ie the one that sends info to the ECU causing hot start problems...

Cheers.