1.9 DCi Laguna 2 EGR/Temperature sensor

[ovenglove]

Hi, I have a problem which is starting to really bug me. Its the first issue I have had with the car and its done 170K now.
I keep losing power, initially the EGR valve was suspected so I had it cleaned and the fault stayed away for a couple of days but now its back with vengeance.
The temperature gauge is also quite erratic jumping all over the place but it does coincide with the loss of power. If the engine is warm but the gauge says its cold then I have sod all power, plus the aircon stops blowing chilled air.
If the temperature gauge is showing a semi-sensible reading then I have power and cold air from the aircon.
It appears to me that when the ECU thinks its is really cold it opens up the EGR to let warmer air in from the exhaust and turns the aircon off because there is no point trying to cool cold air.
The fault only appears once things have warmed up and is gradually getting worse.

I am probably going to replace the temperature sensor and see if that sorts the erratic reading, does anyone think it will fix the EGR/power issue?
If the sensor doesn't fix the problem then I believe there is a voltage regulator that drives it but this is in the instrument panel.

Before the EGR valve was cleaned there was a fuel injection fault displayed which is what lead the garage to believe it was the EGR when coupled with the loss of power. The engine still revs to the red line OK if you can wait long enough!

Any advice or suggestions would be gratefully received.
Iain

[steelcityuk]

My first step would be to get the codes read with a dealer level tool. Until you have the starting point you could be chasing it for ages.

[ovenglove]

When the EGR was cleaned they reset the error codes and since the EGR was cleaned it hasn't displayed the fuel injection error so I assume none are recorded.
I have ordered a temperature sensor so fingers crossed.
I am assuming the fuel gauge sender uses the same voltage source in the instrument panel as that used for the temperature sensor so if the fuel gauge is OK when the temperature is erratic it must be the sensor or cable/connectors between. Hopefully

[steelcityuk]

It sounds as though the EMU thinks there's a fault. Usually the EMU won't authorise the AC compressor engagement if it thinks there's a fault because it judges that power is needed to keep the car running. What data are you getting with the engine running? Are you using a Renault Clip?

[ovenglove]

Hi, I've not got any means of reading the EMU codes as that was done at the garage. But the car still isn't reporting any faults on the dashboard, previously the injection error would pop up quite regularly.

[ovenglove]

Finally got to replace the temperature sensor and all appears to be well now.
Hopefully the fault won't re-appear as it did after the trip to the garage to have the EGR cleaned. If it does then I think its safe to say its an intermittent fault in the wiring/connector and working in that area disturbs it.
Fingers crossed.

Cheers.

[ovenglove]

Ha, would you believe it. 2 days of trouble free driving and today the temperature gauge is bouncing around again. Engine occasionally hicups but not as bad as before, YET!!
Can you recommend a cheapy unit to read the EMU codes by any chance?
Although I am convinced it is a dodgy connection/wire.

Ta
iain

[steelcityuk]

Try to get hold of wiring diagrams and meter out the connections back to the EMU. A cheap generic code reader will be of little help. Save up a bit and buy a Clip clone.

[ovenglove]

Ta, but can you point me in the right direction for a Clip clone, I've tried googling and failed.