2.7 twin turbo - P0404 & lack of power

[keithstype2.7]

Hi All,

I have owned my 2007 S Type 2.7 SE auto for over 9 years with mostly trouble free enjoyment. However recently it started showing the amber Restricted Performance light but when re-started the light went off. This happened more and more often until the car now has a lack of power (as if the turbos don't kick in) and on using an isoft i930 code reader, it is showing P0404 which refers to the EGR performance out of range. Going inside the i930, both EGR valves are showing 5% and from this I understand that they are ok. (Maybe I have misunderstood this??)

I can clear the code temporarily but as soon as the car gets a bit warm the light comes back on. The lack of power is always present.

I have tried EGR cleaner via the air intake and also am using Millers Diesel Oco Plus in the fuel and whilst the car generally runs more smoothly, the lack of power is still present as is the P0404 code.

Has anyone has similar problems and if so, how was it rectified please?

[rosemary]

Hello Keith
I assume as your car is Post 2005, i.e. you quote 2007 and it has Catalytic converters and Diesel Particulate Filters, I assume as such. Do you do short journeys.
Mike Kennedy will confirm that short journeys are an anathema to Diesels and result in blocked filters and Restricted Performance indication coming up. Perhaps an Independent Jag Specialist can help, plus the use of propriety cleaners.I can't comment on the EGR valves mine were changed at 85k because the Jag Main Dealer really didn't have a clue what he was doing to cure a misfire, Meccano would have confused them anyway.
Dave

[jeff1954]

Check the MAP (manifold absolute pressure ) sensor located in the top of the inlet manifold held in by a small torx screw. The top engine cover has to be removed to see it. It gets gunged up after time and can be cleaned or replaced, the latter is probably the best option. Mine caused the restricted performance light to come on and erratic gear changes. Buy a genuine Jaguar one they are the best.

Jeff

[keithstype2.7]

Hi Dave, thank you for your reply. Indeed my car does have a Cat and DPF. I generally only use it for longer journeys and although the fault code P0404 suggest the problem is EGR performance related, it does not specify a particular fault with one or the other EGR valves so it's possible the case is linked to EGR sensor or something in that chain.

Other forum posts suggest it may be MAF or MAP related so I'm checking those before I go any further.

Many thanks
Keith

[keithstype2.7]

Hi Jeff, Many thank you for the reply and MAP suggestion. I will try cleaning the MAP and see if that makes any difference.

Thanks again

Keith

[keithstype2.7]

UPDATE. 20th Jan 2019

I have now removed and cleaned the MAP sensor (an easy and quick procedure) but the Restricted Performance and fault code P0404 remains.
I used a can of Wynn's Extreme EGR Cleaner directly into the air intake (with air filter removed) but this has not affected the fault code.

All of the things I try to remove the fault code have so far failed although each seems to have assisted to improve the general running of the engine and although I don't have full power, the car runs very smoothly.

My next effort will be to replace both MAF sensors.

[keithstype2.7]

For anyone with similar problems, I have now tried the following to eradicate the P0404 fault code and Restricted Performance (RP) issue.

* New Battery
* Service (including oil, oil filter, air & pollen filter and also fuel filter)
* 3 x tins of Wynn's EGR cleaner into air intake
* Millers Diesel Eco Power additive to fuel
* Removed and cleaned MAP sensor
* Removed and cleaned both MAF sensors
I still have the Restricted Performance message with orange dash light and code P0404. The code can be cleared but comes back immediately.
My live datastream info shows very different EGR readings so I will now bite the bullet and have both EGR valves replaced.

I'll update again when this has been done.

[keithstype2.7]

UPDATE 12th Feb 2019.

My car is now fixed.

I have had both EGR valves replaced. The fault code P0404 meant that only one valve was faulty but it seemed a false economy to change just one as it was likely the other would soon become faulty.

My S Type 2.7 now drives like a new car again.

[jeff1954]

Glad you got it sorted, was the job expensive.
Jeff