robertofollia
Member Since: 16 Aug 2006
Location: Sometimes over here, and sometimes over there
Posts: 142
  
|
| MoT time-High CO and low lambda values |
|
Hi all.
I've been usingmy 06 D3 V8 since 2008, when I got it. Besdes front and rear diff and theusual upper and lower arm bushes and ball joints ithas been problem free so far.
But... 2 weeks ago it was MoT time
Being a 2006 vehicle maximum admitted values at fast idle is lambda not lower than 0,97 and CO not higher than 0,20
Last year lambda was 0,992 and CO 0,20. This year lambda values were 0,99 and CO was higher than 0,20 (around 0,21-0,30) , but inspector floored gas pedal several times so it came within values (0,20)
Usually CO at idle had been 0,00 and lambda was 1,00 (2018). The O2 are not shot as they react to gas pedal and there are no strange smells behind exhaust pipes, no leaks (leaks show high lambda usually) and innerpart of exhaust tailpipe is clean.
Air filter and plugs were new.
car is 175k kms (around 109K miles) and still in its original O2 sensors and MAF.
I can notice a slight (very tiny) reduction both in MPG and performance. There are no "reduced performance"messages
But I fear I will not pass next year emission test.
Shall I renew PCV valve? MAF orO2 sensors?
I had a similar problem with my D2 (V8 as well but has nothing to do as it's a different engine) many years ago and it was the MAF. Did not renew O2 sensors though. 15 years later (now it's 120K miles old) it sails through MoT emissions test.
I recall changing as well O2 sensors in my wife's panda just to refit the old ones 1 hour later because the new ones were faulty.
I am reluctant to do th O2 renewal as they are a pig to remove, requiring dropping exhaust and then finding or a leak with rough idle or faulty sensors.
Would be very grateful if you could give me some advice where to look at, in order not to become crazy changing bits "à la Land Rover dealer".
What would you suggest doing first?
Throttle body cleaning and PCV replacing?
MAF sensor replacement?
And as last resort measure O2 sensors?
Best regards to all Regards, Robert
Only a closed filling station can prevent me from reaching my destination
1992 Santana 88"SWB petrol
1995 RRClassic 300Tdi
1999 D2 V8 manual coiler
2004 D2 Td5... SOLD!
2006 D3 V8 SE
|
 16th Feb 2020 6:54 pm |
|
|
El Capitano
Member Since: 04 Dec 2018
Location: Hartlepool
Posts: 20
 
|
You need access to a decent diagnostic tool to see what your fuel trims and your lambda sensor outputs are, these will help to identify your problem.
I guess the Gap tool will do this but other diagnostic readers are available!
If you don’t have access to one then any decent garage will be able to scan the car.
It could be as simple as cleaning the MAF sensor.
|
| 16th Feb 2020 11:41 pm |
|
|
robertofollia
Member Since: 16 Aug 2006
Location: Sometimes over here, and sometimes over there
Posts: 142
|
Hi, thanks for the reply.
I will try to clean myself the MAF sensor very carefully.
Have only had them cleaned twice in another vehicle (Disco 2 V8). The first time it was a mechanic who cleaned it (and ruined it). The second one I cleaned it 10 years ago and still soldiers on.
Will take some time as the D3 is used by my brother mow and it will take me a month before I see him again. Will report news, though.
As far as readers go, I have faulmate FCR's but you cannot get live data. I have got another reader (generic, not D3 specific, which can get live data and is CAN-enabled, so might do the trick as well). I had not seen any codes thrown, though, nor MIL lights illuminated.
Best regards Regards, Robert
Only a closed filling station can prevent me from reaching my destination
1992 Santana 88"SWB petrol
1995 RRClassic 300Tdi
1999 D2 V8 manual coiler
2004 D2 Td5... SOLD!
2006 D3 V8 SE
|
| 17th Feb 2020 1:02 pm |
|
|
