C5 - Engine Temperature High on computer and Gauge

timborob · Unread post by **timborob** » 23 Jul 2010, 17:48

Hi

I can't believe it as on the way home I thought I'd rev the car abit more
and be a abit brisk and suddenly the "Engine Temp High" came on the computer aswell as the Temperature Gauge right up in the red!

Anyway I had only been driving for about 5 minutes and pulled over when it was safe to about a minute later,I then pulled the bonnett but found nothing overly hot.

I waited about 5 minutes and started the car back up but still in the red
and computer bleeping at me.

Looks like i have a stuck Engine Temp sensor,has this happen to anyone else on here?

And how do i check if it has stuck and change etc

These C5's seem to have too many electrical glitches to me

I am now back at home with the car and will retry later to see if its still stuck or cleared itself.

Citroenmad · Unread post by **Citroenmad** » 23 Jul 2010, 22:13

Hi Tim,

Ive had a similar issue with a HDi engine, it was with my old Peugeot 206 but it had the same engine (2.0HDi) and electronics as the C5.

'IF' yours is the same problem then the following might be of interest ...

Every now and again, as i had been driving the car for a few minutes, sometimes even on start up, the computer there would be a beep and the computer display would warn me of the coolent temperature being too high. I just ignored it as it was usually as i had set off and knew the car would be cool enough.

However it rarely effected the actual temperature gauge, whih usually read normal. However it was getting worse and the needle would sometimes sit a bit higher than normal, or the needle would vary from high to low temp quite quickly.

I replaced the coolent temp sender and all was well after that.

Its around £12 from the dealers and its a few minute job to fit yourself. It goes in the side of the engine block and on a C5 its really very easy to get too. Just be quick to replace it as some coolent will be lost when you remove the old one. Though i didnt lose enough on mine to warrant a top up.

Hopefully it is that and will be cheap and painless for you to replace.

timborob · Unread post by **timborob** » 24 Jul 2010, 00:00

Hi Chris

Thanks alot for the reply and Info.

I hope it is just this Coolant Temperature Sender and I will look into trying to replace it soon

I haven't got a manual to look at yet but will do my best to locate it and get to my local dealer and buy a new one.

I did retry my car earlier after cooling down for 2 hours + and the gauge just shoots straight up as high as it can into the red zone and the computer bleeps and displays "Engine Temp too high"

Strange it would just fail like that especially as it's really the first time I have revved the car meanifully past 4,000 rpm so I wonder was that the reason somehow or just coincidence?

I did read you said an "Itailan Tune up" can work wonders
and thought it may help my Clutch problem

Citroenmad · Unread post by **Citroenmad** » 24 Jul 2010, 09:15

It does seem odd that it has happened so quickly, it might well be somehting else. Keep a check on the temperature of the engine and make sure it isnt getting too hot. It might well be another temp sensor a miss somewhere, it may be a code stored in the ECU. But my first guess would be this sender, its very easy to replace and wont last forever.

I do like a good italian tune up!

The C5 SX failed its MOT the other day on emissions. Probably to do with the way my sister drives it, never getting past 2000 rpm. So i stuck in some Forte diesel cleaner in with the fuel and took it for a good blast using full use of all the rev range and keeping the revs high. I then stopped, took off the air intake pipe after the MAF sensor, reved the car and sprayed in some forte air intake cleaner. This cleans up anything in the intake system, any sensors, EGR (though its not connected on this particular C5)it should even get to the turbo. However, after another good blast down the motorway at 4000+RPM it feels so much livlier. It really takes off now, much nippier and mre responsive. So this morning im about to take it back to get a retest done on the emissions, hopefully it will pass (fingers crossed)

Our 05reg C5 has been getting a bit difficult to drive lately, it would want to stall quite easily and the power would hesitate and it felt slower. A code read brought up a problem with the EGR valve. Out of curisity we did the same as we did on the C5 SX with this one and the car is transformed. Its back to how it was when we got the car, It flys now, it pulls away on tickover without the need to rev it, MPG has improved and its so much more responsive. So for now at least, the EGR order of £200+ is on hold as the car seems cured.

Just so my C5 didnt feel left out, i gave it the same treatment too. A good dose of intake cleaner and then a very good blast around. The performance is great now, really feels much more lively.

So im very pleased. Somehting i will have to be doing every 6 months or so i think.

I hope the C5 SX goes through its MOT fine after that.

Not that it will help your problem, but i thought id share

mooseshaver · Unread post by **mooseshaver** » 24 Jul 2010, 10:03

Citroenmad wrote:, reved the car and sprayed in some forte air intake cleaner.

At the same time? How do you reach both?
I think this is what my 1.6 HDi needs. Its had the new egr valve and that was excellent for a while but has started hesitating again.

I' also thinking if new air filter if I can work out how to remove the top of the airbox without the whole box coming adrift. My brother bnaged the dirt out of it a while ago, its filthy, and they only get changed every 42000 miles or so normally.

Unread post by **Old-Guy** » 24 Jul 2010, 10:56

If might be worth while checking the connections on the temperature sensors (there's often more than one). Usually, sensor circuits are designed so that they 'fail safe' - you get a 'false alarm' rather than driving along in blissful ignorance.

You going to have to 'drain' some coolant out to change any dead sensor(s), if the car is more than 4 or 5 years old, it might be worth changing the thermostat too as they deteriorate over time (as much as miles). Often the first you know about a dieing thermostat is overheating on a long hot motorway trip. Been there, done that, several times.

timborob · Unread post by **timborob** » 24 Jul 2010, 16:03

Citroenmad wrote:It does seem odd that it has happened so quickly, it might well be somehting else. Keep a check on the temperature of the engine and make sure it isnt getting too hot. It might well be another temp sensor a miss somewhere, it may be a code stored in the ECU. But my first guess would be this sender, its very easy to replace and wont last forever.

I had a look earlier this morning and think I found the Sensor on the RHS of the engine and it has a green plug with Sicma (<PRT> ?) written on it.

I pulled on the plug and it came off very easily and can see it should clip on and has been broken, So i pulled it off and push back on as hard as i could and then turned the ignition and now Temperature is back to normal

Obviously not quite sure if this is the full cure but will be driving it later and will see how it goes

Citroenmad wrote: I do like a good italian tune up!

The C5 SX failed its MOT the other day on emissions. Probably to do with the way my sister drives it, never getting past 2000 rpm. So i stuck in some Forte diesel cleaner in with the fuel and took it for a good blast using full use of all the rev range and keeping the revs high. I then stopped, took off the air intake pipe after the MAF sensor, reved the car and sprayed in some forte air intake cleaner. This cleans up anything in the intake system, any sensors, EGR (though its not connected on this particular C5)it should even get to the turbo. However, after another good blast down the motorway at 4000+RPM it feels so much livlier. It really takes off now, much nippier and mre responsive. So this morning im about to take it back to get a retest done on the emissions, hopefully it will pass (fingers crossed)

Our 05reg C5 has been getting a bit difficult to drive lately, it would want to stall quite easily and the power would hesitate and it felt slower. A code read brought up a problem with the EGR valve. Out of curisity we did the same as we did on the C5 SX with this one and the car is transformed. Its back to how it was when we got the car, It flys now, it pulls away on tickover without the need to rev it, MPG has improved and its so much more responsive. So for now at least, the EGR order of £200+ is on hold as the car seems cured.

Just so my C5 didnt feel left out, i gave it the same treatment too. A good dose of intake cleaner and then a very good blast around. The performance is great now, really feels much more lively.

So im very pleased. Somehting i will have to be doing every 6 months or so i think.

I hope the C5 SX goes through its MOT fine after that.

Not that it will help your problem, but i thought id share

Well thanks for the Info and hope your SX now passing the MOT with flying colours!

I could really do with someone like you looking over mine C5
and giving it a treat as abit of an amateur when it comes to EGR valves, cleaning + changing MAFs at present.

Shame you are such a long drive from me

timborob · Unread post by **timborob** » 24 Jul 2010, 16:08

Old-Guy wrote:If might be worth while checking the connections on the temperature sensors (there's often more than one). Usually, sensor circuits are designed so that they 'fail safe' - you get a 'false alarm' rather than driving along in blissful ignorance.

You going to have to 'drain' some coolant out to change any dead sensor(s), if the car is more than 4 or 5 years old, it might be worth changing the thermostat too as they deteriorate over time (as much as miles). Often the first you know about a dieing thermostat is overheating on a long hot motorway trip. Been there, done that, several times.

Hi Old-Guy

Thanks for the reply and advice.

I did find the connectors loose on the green plug I found and i hope that
it is what the problem is and will look into replacing it or atleast securing better

The thermostat has been already been replaced as i had unfortunately had a HeadGasket Failure on this car and only got it back end of May
Maybe it was at this time that the sensor plug got broken
who knows?