engine cooling fan runs for six minutes after switchoff - is it normal?

Hi everyone,
I recently bought a 2005 C3 Desire 8 valve. It has a problem cold starting - takes five attempts, but starts OK when warm.
However, after running the engine on the drive or after taking it for a drive, the cooling fan continues to run for what I assume is the six minutes in the handbook. Is this normal for all C3s to do this? I have just replaced the temperature sensor next to the air filter. My diagnostic meter said the running engine temperature was 101C when hot and 87C when cold. When I disconnected the sensor it showed 71C. The new sensor shows 68C when cold. I was working on the theory that the starting problem was caused by the sensor telling the ECU that the engine was already warm when starting. Thus the fuel supply etc would be less than was actually required? I did have leaky injectors and found that a squirt of brake cleaner into the air intake before the throttle housing made the car burst into life when cold. I have also replaced the crankshaft sensor. However, although slightly improved it is still reluctant to start when cold. I am following all the C3 bad starting threads. I also think that these topics should be marked as RESOLVED when the problem is found.

I cannot recall walking past any car with a running fan after switch off. It did happen to my Kangoo earlier this year when I had a small shortage of water, but only a couple of minutes at the most. Any PMs are welcome, or add to this thread. Thanks

ronc3 wrote:I also think that these topics should be marked as RESOLVED when the problem is found.

Agreed, but not all fixes are the same for different faults that look similar. There also seems to be a problem to get some owners who have either resolved their issue or scrapped/traded in the car to update their topic. How do you suggest this is policed? (all suggestions welcome)

ronc3 wrote:I was working on the theory that the starting problem was caused by the sensor telling the ECU that the engine was already warm when starting. Thus the fuel supply etc would be less than was actually required?

I like your thinking, makes sense to me.

ronc3 wrote:I cannot recall walking past any car with a running fan after switch off.

I have seen a few, but my C3 is a diesel, but I will talk to other C3 petrol owners to see if their fan continues after a run.

I does sound like a cooling issue, have you drained, flushed and refilled when you changed sensors? Just looking at the colour of the coolant can give an insight to the state of the cooling system and its previous maintenance.

Hi C3driver52, thanks for your reply and info'.

I agree with what you say about car problems and RESOLVED cases having different solutions and if members gave their findings then a GURU like yourself could do a write up for some sort of flow chart or check list?

I have not drained or flushed the system as the car took threw a wobbler last week. We have driven down the M6 a few times without any problems. Last week my wife took the C3 down the M6 to pick up my grandson and the cars temperature gauge went to the red she just carried on! She parked up to do some shopping and let it cool down a bit before coming home steadily. On the drive the fan was running flat out, then stopped, then spun a few times, then sped up again etc. As soon as it started the next day it soon went to red again. I was away on holiday over the weekend and have been thinking that the thermostat is stuck or faulty - or an ECU fault? I will swap the old temperature sensor back in (just in case the new one has gone faulty). Then if that does not make a difference I will have to change the thermostat! I will keep you all posted and hopefully return to the original bad starting problem

Update!
I was reading a Peugeot 206 1.4 petrol 2005 thread with the same problem - starting after 4/5 attempts. The poster said he ended up fitting a new Bosch coil pack and a new set of Bosch spark plugs and it started first time and every time since! Apparently the coil pack was not up to scratch all though it ran the engine fine once started. So I went and bought a Bosch coil pack and spark plugs last Thursday. Before attempting to start I pressed the fuel rail valve to check their was petrol pressure and there was. It started on the second flick of the key - I thought sorted, but left it for the next day to try again. So Friday morning I gave it another go and it was still the same as before - fifth attempt before it kicked into life. MY son later checked that there was pressure at the fuel pump and we have ruled that out for now. I will try sort out the thermostat fan issue. I have also removed the Management ECU and looking to see who will be the best company to have it tested and checked out. Will keep everyone updated. At least I will be able to rebuild the tumble dryer that is strewn across the garage floor while I wait!!!

ronc3 wrote:At least I will be able to rebuild the tumble dryer that is strewn across the garage floor while I wait!!!

Thanks for the update so far

Hello again,
I asked BBA Reman about ECU testing and they said that they were unable to test the SAGEM ECU. So I asked the ECU Doctor in Plymouth, who offer a twelve month guarantee, if they could test and repair the SAGEM. This they could do, but said that the symptoms I described may not shown up during testing of the ECU?
I started to replace the thermostat but noticed a cable with a white plug cable tied to the loom behind the injectors. I was wondering if this should connect to a sensor on two-sensor thermostat housing, or if it a sensor that is not on my model or year. It has a white plug and the cables are violet/green-yellow/violet. I know that the green-yellow is earth. I have been through my Haynes Manual diagrams but cannot find a reference to this cable. Does anyone have an idea what this cable is for? I still have not sorted the tumble dryer either!!! Thanks.

Hi,
Quick update. Had the car at Wigan Auto Electronics for four days who checked all the wiring and connectors but could not find a problem. Their conclusion was that it was down to the ECU. So I am going to send it of to the 'ECU Doctor' in Plymouth in the next few days. They have a few options if it is no-fault-found or unrepairable. Still not sorted the tumble dryer out either. Cheers.

Sorry I did not add an update earlier. Sadly there was no eureka moment when the fault was cured. After the erratic temperature gauge display and replacing the temperature sensor along with the anti-freeze, my wife said enough was enough. She traded it in for a Yaris - we lost a lot of money on the C3. The garage I that PX'd the car said they would let me know if they cured the problem. I think it went to the auction and then the breakers. Thanks to everyone who offered ideas and solutions to help me. I'm no big fan of the Yaris as I think the C3 had a better boot, dash, seating and was more practical. Good luck to all you C3 fans.

Hi,
A very, very late update, I checked the MOT status of the C3 and it is and has all the passes to keep it on the road. So someone has either cured it or is just ignoring the problem and the temperature warning light? Perhaps it's been cloned - who knows? Good luck to them. Cheers.

Regards,
Ron.