[Harris9119]

Hi All,

I recently been getting a rough idle sometimes when warm. Also when first starting when cold appears to missfire then settle down as it should. This happens on every cold start.The car drives fine and doesn't seem to be suffering any power loss. No fault codes showing.

I have tried changing the fuel filter along with a full service, injector cleaner.

Any help would be much appreciated

James

 

[wilf]

Possibly glow plug(s) - but some more details about the car's age, mileage, service history would help.

 

[Harris9119]

Possibly glow plug(s) - but some more details about the car's age, mileage, service history would help.

Wouldn't glow plugs show a fault code?

Car has full service history, recent cambelt change around 2000 miles ago along with new r/h turbo. Year is 2010 with 117,000 miles on the clock.

Could it be possible injector fault? But I presume the wouldnt only happen when warm or just at start up.

Thanks in advanced

 

[ninjag]

No harm checking and cleaning the MAP sensor and both MAF sensors. Doesn't cost anything and a good maintenance task anyway. Perhaps try a can or two of Wynns Dry Fuel.

Have you got a scanner which can read Jaguar specific codes and sensors?

 

[FCS]

You really need to do a diagnostic. icarsoft is easy to use. Could be a bad dose of fuel but doubtful. I would check for air leaks around inlet manifold while doing as Graham suggests above.

 

[Harris9119]

I should have mentioned, I have already cleaned both MAF sensors,Map sensor, intake temp sensor. I have run Liqui Moly diesel purg 1 can through the tank, other can directly through the fuel filter into injectors. I have also used icar soft diagnostics tool.

 

[FCS]

It looks like you have tried most things. It may be worth having a look at the turbo actuators if one of them is a bit sticky it may throw things off. I would have a good look for manifold leaks as well. May be worth taking off the throttle body and giving that a good clean if you have not already done it.

 

[Harris9119]

HI all,
Thank you very much for all your responses. I had a good look round inlet manifold last night and checked turbo actuators. No cracks in inlet manifold and actuators seems to be moving freely. Check all the lines for leaks unable to find any thing on that front. Took off the throttle body also cleaned and checked seals for leaks.

I did find the intake air temp sensor damaged the wires them selves seem fine but the plastic casing in damaged. I gather this could effect readings from this sensor. Let me know your thoughts (see attached picture)

James

 

[ninjag]

I'm sure a malfunctioning intake temp sensor can result in poor idle and despite the absence of a fault code, personally I would still replace that. It also doesn't look particularly clean?

 

[Harris9119]

Yes I think it could be the culprit. I have ordered one, the only place that I could get one from was jag for £75. I'll pick it up tommorow and try it. The main element if clean but as you can see in the picture there is some carbon deposit further down the element.

Will let you know how I get on

 

[ninjag]

Yes I think it could be the culprit. I have ordered one, the only place that I could get one from was jag for £75. I'll pick it up tommorow and try it. The main element if clean but as you can see in the picture there is some carbon deposit further down the element.

Will let you know how I get on

Please do, will be interesting to know. It's amazing how such a sensor impacts so many things!

 

[Harris9119]

Please do, will be interesting to know. It's amazing how such a sensor impacts so many things!

Update

Unfortunately the replacement sensor has not worked and the problem still persists.

I'm running out of ideas

 

[Harris9119]

Should the engine cut out if the 1 or both of MAF sensors are connected ? As I have found mine keeps running and gets rid of the rough idle

 

[Lomond]

How about swapping the MAF sensor about (bank 1 with 2) to see if that changes anything?

 

[Harris9119]

I will give it ago tommorow. Would you be willing to unplug yours and see if it cuts out?

 

[Gav]

I’d expect it still to run, the ecu will just use a predetermined value and go with that.

 

[Harris9119]

I’d expect it still to run, the ecu will just use a predetermined value and go with that.

I can imagine your proably right. However would this rule out a faulty injector ? As surely a faulty injector would still cause the rough idle

 

[Gav]

Yes it would faulty is faulty and you’d still have a problem. The fact that it get rid of the problem suggests it air related, check all the intakes.

 

[Lomond]

Yes it would faulty is faulty and you’d still have a problem. The fact that it get rid of the problem suggests it air related, check all the intakes.

At least you may pin it down to a dodgy maf sensor.
Start with the cheap/easy stuff before getting elbow deep!

 

[Harris9119]

Hi All,

Just an update

plugged in my torque code read which brought up no fault code. Then once unplugged I had the message for dpf full pop up so I code read it with icarsoft and got following fault codes attached.

It seems a bit strange how they've both suddenly popped up now once read with another code reader maybe coincidence?