L322 Black smoke on kickdown

This site contains affiliate links for which LandyZone may be compensated if you make a purchase.
If the EGR's are blanked, how is cleaner going to affect things?
Because the egr's are still in the system and air still runs through them. If they are blocked then the air is reduced causing the code to be thrown out. That's what I was told last night by another fella. I've only blanked the recirculation pipe. Not the actual egrs. Is he wrong then? I had the egrs blanked because it was showing a fault with them. Soon as they are blanked,the egr fault went and now it's given out p023d. That was the day after I had them blanked.
 
Blanking them won't get rid of a fault though. It will stop the gas going into the inlet but if the EGR is showing as out of range or faulty in whatever way, that will remain. The only way you can get rid of that is to code them out but even then it will still show a fault if scanned but it won't cause a "restricted performance" mode on the car while driving.

Mine used to smoke really badly under hard acceleration when I got it but I bought it broken and found the split inlet manifold. I have no idea how long it had been driven like this prior to my ownership and whether it had just been gently pootled about for fear of limp mode. Once I'd fixed the issues with it, the smoke stayed for quite some time but it did lessen and now I only get a bit of grey/brown when I make it work hard as you'd expect. Recently I had some issues to work through that meant it spent a lot of time on short runs and idling for extended periods so naturally it did smoke a fair bit when I started using it properly again.

I guess where I am going with this nausea is that if you aren't seeing a performance issue or any faults, get it out on some long drives and see if it starts to clear up, you may be looking for an issue that doesn't really exist. Is the P023D back since you've swapped the Map sensors about?

Why not take the EGR blanks out and see if the P023D goes away and your EGR fault returns? You have one less bolt to undo than anyone else ;). I love that it was fine when the guy did it but mysteriously the bolt just sheared off!
 
Blanking them won't get rid of a fault though. It will stop the gas going into the inlet but if the EGR is showing as out of range or faulty in whatever way, that will remain. The only way you can get rid of that is to code them out but even then it will still show a fault if scanned but it won't cause a "restricted performance" mode on the car while driving.

Mine used to smoke really badly under hard acceleration when I got it but I bought it broken and found the split inlet manifold. I have no idea how long it had been driven like this prior to my ownership and whether it had just been gently pootled about for fear of limp mode. Once I'd fixed the issues with it, the smoke stayed for quite some time but it did lessen and now I only get a bit of grey/brown when I make it work hard as you'd expect. Recently I had some issues to work through that meant it spent a lot of time on short runs and idling for extended periods so naturally it did smoke a fair bit when I started using it properly again.

I guess where I am going with this nausea is that if you aren't seeing a performance issue or any faults, get it out on some long drives and see if it starts to clear up, you may be looking for an issue that doesn't really exist. Is the P023D back since you've swapped the Map sensors about?

Why not take the EGR blanks out and see if the P023D goes away and your EGR fault returns? You have one less bolt to undo than anyone else ;). I love that it was fine when the guy did it but mysteriously the bolt just sheared off!
Yeah me too mate. I'm just going through everything I can. It may still be the same issue as when the egr codes came through. It's just moved up the line codewise. The fella I spoke to last night said that if a blocked egr was the reason it was going into limp then the problem will still exist even though I've taken the recirculation pipe out and blanked it. Just that now the turbo will be over boosting as its struggling to get the right amount of air.i havnt a clue what's going on. I'm going to run some egr cleaner though it and give it a boot and then try again to see if I can find a leak in the manifold. I got told to spray some brake cleaner over the manifold while the engine is cold but running and if the revs change at any point I've got a leak. Does that sound like something I should try??
 
I doubt that will help you as your issue is more likely air escaping rather than being drawn in. If you spray brake cleaner on a petrol engine the revs will in crease if it has a vacuum leak but that's a really high powered detonation for a diesel, it's not good for any engine (prolonged use) but diesels will knock like hell if you put solvent in them.

If you can get an aerosol lid or something in your boost pipe as a reducer to an airline you might get a bit more of a chance to find a leak if you have one.
 
I doubt that will help you as your issue is more likely air escaping rather than being drawn in. If you spray brake cleaner on a petrol engine the revs will in crease if it has a vacuum leak but that's a really high powered detonation for a diesel, it's not good for any engine (prolonged use) but diesels will knock like hell if you put solvent in them.

If you can get an aerosol lid or something in your boost pipe as a reducer to an airline you might get a bit more of a chance to find a leak if you have one.
Engine idling, turbo's will be doing FA so there should be vacuum in the manifold.
 
Thats my next step mate. Took it to Brighton today from my home in portsmouth for a work meeting and it went into limp mode over 10 times. Every time I went over 2500 revs and up to speed or over 2000 revs uphill. And there's alot of hills🤦‍♂️ if i boot it quickly and then let it drop its fine.just when i go full throttle and get over 40 or 50.have to use manual changing or feather the pedal to make sure it stays under the revs. I've sprayed 2 cans of egr cleaner into the air pipes from the air box and its kicked out alot of crap but still into limp. It seems worse since I got the egr blanked so I'll remove the blanks and Refit the recirculation pipes and then get some air into the manifold and see if I can get somewhere with that. Its sounding more and more like the manifold but I can't hear any hissing. Still got full boost on the turbos and no oil in the pipes so I really don't think it's either of the turbos. You lads are a great help and I'm learning more and more about the RR V8. I've always been an Audi or BMW man so this is all new to me. Thank you for your help.I'll get back under the bonnet tomorrow and let you know how I've got on.
 
Engine idling, turbo's will be doing FA so there should be vacuum in the manifold.
I'm going to put the recirculation pipes back in tomorrow as it's got worse since I blanked them. Then get some air into it with a compressor and see if it's the manifold mate. Thanks for the help so far mate. Much appreciated 👏 I will get it sorted if it's the last thing I do!!
 
Engine idling, turbo's will be doing FA so there should be vacuum in the manifold.
Agreed but if the split only opens under boost then from my experience there won't be enough of a gap to get the brake cleaner through it to have any noticeable effect on a V8 with the volume of air being pulled through an unrestricted manifold. You'll need positive pressure to open it not negative.

No harm in trying but I don't think it will be a conclusive test.
Thats my next step mate. Took it to Brighton today from my home in portsmouth for a work meeting and it went into limp mode over 10 times. Every time I went over 2500 revs and up to speed or over 2000 revs uphill. And there's alot of hills🤦‍♂️ if i boot it quickly and then let it drop its fine.just when i go full throttle and get over 40 or 50.have to use manual changing or feather the pedal to make sure it stays under the revs. I've sprayed 2 cans of egr cleaner into the air pipes from the air box and its kicked out alot of crap but still into limp. It seems worse since I got the egr blanked so I'll remove the blanks and Refit the recirculation pipes and then get some air into the manifold and see if I can get somewhere with that. Its sounding more and more like the manifold but I can't hear any hissing. Still got full boost on the turbos and no oil in the pipes so I really don't think it's either of the turbos. You lads are a great help and I'm learning more and more about the RR V8. I've always been an Audi or BMW man so this is all new to me. Thank you for your help.I'll get back under the bonnet tomorrow and let you know how I've got on.

I couldn't hear any hissing on mine either. It was just a lucky find. for me as I was (like you) mostly a German car guy, not these things. I will say that the crack in mine was really hard to see too.
 
Agreed but if the split only opens under boost then from my experience there won't be enough of a gap to get the brake cleaner through it to have any noticeable effect on a V8 with the volume of air being pulled through an unrestricted manifold. You'll need positive pressure to open it not negative.

No harm in trying but I don't think it will be a conclusive test.


I couldn't hear any hissing on mine either. It was just a lucky find. for me as I was (like you) mostly a German car guy, not these things. I will say that the crack in mine was really hard to see too.
I've got my hands on an air compressor so I'll make a funnel type adapter in my workshop to connect to the right intercooler hose and get some pressure into it and see what happens then. Does anyone know what the max pressure I can pump in is? Either way it's going to hiss or blow🤦‍♂️ I'll check how much a replacement is just in case the manifold blows but it's really the only thing it can be now. Took it out again tonight and it's still quick off the mark with plenty of boost there. Just blinds the car behind me 😅 staying clear of hills and motorways.thanks again. Lucky I love the motor when she's behaving or she'd be in the scrap yard. I'm totally in love with it but it's a love hate relationship atm haha
 
I've got my hands on an air compressor so I'll make a funnel type adapter in my workshop to connect to the right intercooler hose and get some pressure into it and see what happens then. Does anyone know what the max pressure I can pump in is? Either way it's going to hiss or blow🤦‍♂️ I'll check how much a replacement is just in case the manifold blows but it's really the only thing it can be now. Took it out again tonight and it's still quick off the mark with plenty of boost there. Just blinds the car behind me 😅 staying clear of hills and motorways.thanks again. Lucky I love the motor when she's behaving or she'd be in the scrap yard. I'm totally in love with it but it's a love hate relationship atm haha
I wouldn't go much higher than 1bar, certainly not over 1.5 bar.
 
Just had another thought on this, can you get someone to tell you if it’s smoking on one side more than the other. An unpopular issue could be a failing/failed turbo. If it’s letting by and burning oil that would give you excessive smoke and a boost mismatch error.

You could try pulling the hoses off the inlet and revving it to see if you get smoke before the inlet and then you can rule out fuelling being the issue as that will be before the injectors get involved.
 
Just had another thought on this, can you get someone to tell you if it’s smoking on one side more than the other. An unpopular issue could be a failing/failed turbo. If it’s letting by and burning oil that would give you excessive smoke and a boost mismatch error.

You could try pulling the hoses off the inlet and revving it to see if you get smoke before the inlet and then you can rule out fuelling being the issue as that will be before the injectors get involved.
So,if I get smoke from the top hoses I've got a failing turbo?
 
Possibly. If you've got smoke before combustion then you have a route to follow to the cause. Not certain but I think they have separate intercoolers so it should isolate the issue to one side or the other if it that's the cause. It's another free test that you can do.

Had a little search around and found this, it must be a video I watched some time back as it seems familiar and probably was gave me the idea. .

At the end they have the top hoses off and you can see what I was trying to describe.
 
Possibly. If you've got smoke before combustion then you have a route to follow to the cause. Not certain but I think they have separate intercoolers so it should isolate the issue to one side or the other if it that's the cause. It's another free test that you can do.

Had a little search around and found this, it must be a video I watched some time back as it seems familiar and probably was gave me the idea. .

At the end they have the top hoses off and you can see what I was trying to describe.

I will try that when I get home. I've done all the same data stream and all of my values are the same on both banks. I did take some photos of the values which were the same or near same as the ones he got off the good bank. So hopefully, fingers crossed its not the turbo. Looking more like a manifold leak.
 

Attachments

  • 20240222_185813.jpg
    20240222_185813.jpg
    166.5 KB · Views: 89
  • 20240222_185804.jpg
    20240222_185804.jpg
    153.4 KB · Views: 90
  • 20240223_133436.jpg
    20240223_133436.jpg
    241.3 KB · Views: 83
I did think about that after my post as I recall you had similar values. It won't take much to get a correlation error. I had this on mine:
P023D-22StateIntermittentManifold absolute pressure - turbocharger/ supercharger boost sensor A correlation

It's worth noting that "Sensor A" doesn't mean that it is on bank 1, it is simply that sensor A doesn't match sensor B in this case.

"Bank 1 (or A)" for OBD codes is realistically just for the first set of cylinders, it is just the way the codes are designed. You will always get "Bank1" even if it is a 4 cylinder engine, not sure what you get for Cyl 6, that would be bank one in the case of a V12 or bank two for a V6... I'm sure someone with greater knowledge than I will be able to chime in here. Anyway, my point was to just be wary of the bank number in the codes as it can lead you down the wrong path.
 
Back
Top