2.7 v6 lumpy idle and misfire

[GingerPower]

Hi, 

I'm hoping someone will have a solution to this problem. 

My 2006 2.7 V6 diesel S-type has had an intermittent running issue, what happens is once the engine is up to temperature the exhaust will sound louder and then the engine will have a slight misfire when cruising at around 1500 - 2000 rpm. When I come to a stop it will idle and be really lumpy like it is going to stall. 

I've had a diagnostic on it when it's been doing it and no codes come up and where it's an intermittent problem I'm thinking it's possibly a problem with the ECU as the climate control is also broken and only blows hot. Also my service required light came on much earlier than it should and the mileage till service kept changing and going up and down, now it just shows the red light and 'service required' 

I've had a faulty injector changed, EGR valves cleaned and an air flow sensor changed. 

Apart from the ECU I'm out of ideas, has anyone had a similar problem if so what is it that it needs?

Cheers

[GingerPower]

Another point I should say is that when it was doing it I tried disconnecting the battery and resetting the ECU and it seems to have stopped it doing it for now. 

[JOE-DOT-COM]

Hi

Still sounds like EGR valves to me, they might be clean but they could still be faulty

the ecu monitors both egr's, so the electronic's inside them could be faulty

could also be faulty actuators on the turbo's, they are electronically controlled, but you usually get fault codes for both of these

you could do with a OBD logger to monitor the ecu and record any fault codes, some faults will automatically clear as soon as the fault clears

also may be a air leak, a split hose or perished hose with cause faults under load and clear when driven normal/light pedal

a descent app and OBD tool can monitor most engine parameters and can help find faults like air leaks by monitoring fuel trims

cheers

Joe

[GingerPower]

Thanks, Joe. I'm going to have them checked out tomorrow. 

Are EGR's expensive do you know?

[Lazlo Woodbine]

I don't know about the engine but this is a good site for the 2002.5 onwards climate control:

http://jaguarclimatecontrol.com/

[Carole Simpson-Hadley]

Hello Jamie

Ref your problem and costing of EGR valves, have a look at the thread by Actros entitled "S type black smoke" ..... costings are mentioned there, although do be aware that changing them can be a little time consuming (we had our S done last year).

Good luck

Carole & partner

[GingerPower]

I've booked it in for a carbon clean on a few recommendations as a last stitch attempt to fix it cheaply. We'll have to wait and see what that can do...

[JOE-DOT-COM]

17 hours ago, GingerPower said:

I've booked it in for a carbon clean on a few recommendations as a last stitch attempt to fix it cheaply. We'll have to wait and see what that can do...

Hi

If its a faulty EGR, No amount of cleaning it, will cure it

Cost of a carbon clean would of covered a pair of EGR's, If It is egr's

cheers

Joe