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max535

Charge-air pressure problems

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My 535d had suddenly lost all low end power, having cleared and scanned for codes i seem to have 2 issues:

 

4530 Charge-air pressure control
41AB Charge-air pressure sensor

 

Most likely 41AB has been there for a while, I had a little look thinking 41AB was the MAP sensor, it was covered with crud so i gave it a blast with some contact cleaner, that seemed to clear it out but didn't make any difference... then after searching around a bit more i think the issue may actually be the intake air temperature sensor, I've seen that this can get oil on it which can trigger this code so i may try cleaning that tomorrow...

 

While i was rooting around i noticed all the vacuum lines looked old and the braiding was frayed at the ends, i wiggled the end going into the vacuum tank and it just popped off, the end was all split and cracked so im fairly sure a lot of the other hoses are going to be the same and need replacing...

 

So my questions are does anyone have any more insight on the 41AB code?

 

And what do people think about replacement vacuum hose these days, shall I just order some 3.5mm braided hose from GSF, or get some silicone hose and if its silicone it it better to stick with 3.5mm or go to 4mm? (Everywhere that sells silicon only has 3mm or 4mm)
 

I heard 5m is enough?

 

Sorry if its been discussed a million times!

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Typical codes for vac issues, leaking like a sieve, slow pressure transducers and switchover valves.

The cheap braided hose isn't very good but will do, otherwise pop onto Ramair's ebay store and order their 3mm silicon, you will need 6m but I buy red, blue and black as the 535 uses all 3, red for the front switchover, blue for the turbo one and black for the rest so you have plenty if you buy 9 meters.

Edited by GoNz0

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Hey Gonzo thanks for replying, yes it seems this is all quite typical, i know from the history of the car one of the pressure transducers was replaced 2 years ago so hopefully i don't need to replace any. Silicone is probably the better choice and i know a lot of people use 3mm ID which works just fine but I'm leaning towards 4mm as a lot of people say its sturdier, just personal preference i guess. I'd like to do them colour coded but how much of each colour should i order?

 

I'm a bit concerned about the area under the inlet manifold, it seems to be covered in grease and grime including on the glow plugs, now i was told when i bought the car that the swirl flaps had been removed (i have no evidence) so hopefully that means the inlet manifold seals were replaced as part of the delete kit, and i think that means all that grease and grime is probably due to the rocker cover gasket leaking, I'm not sure where else it would come from?

 

Regards code 41AB I had a look yesterday and cleaned the intake temp sensor, it was oily so i cleaned it with contact cleaner and cleared the code but that didn't help and the code came straight back after a drive. I've also read that this code can be related to DPF delete, but i also see there is a fair amount of oil on the intake piping especially above and below that sensor so maybe i need to look at the charge pipe seals, who knows it could be a number of things but i think ill come back to this later on as other leak issues may be related...

 

 

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Hey Gonzo thanks for replying, yes it seems this is all quite typical, i know from the history of the car one of the pressure transducers was replaced 2 years ago so hopefully i don't need to replace any. Silicone is probably the better choice and i know a lot of people use 3mm ID which works just fine but I'm leaning towards 4mm as a lot of people say its sturdier, just personal preference i guess. I'd like to do them colour coded but how much of each colour should i order?
 
I'm a bit concerned about the area under the inlet manifold, it seems to be covered in grease and grime including on the glow plugs, now i was told when i bought the car that the swirl flaps had been removed (i have no evidence) so hopefully that means the inlet manifold seals were replaced as part of the delete kit, and i think that means all that grease and grime is probably due to the rocker cover gasket leaking, I'm not sure where else it would come from?
 
Regards code 41AB I had a look yesterday and cleaned the intake temp sensor, it was oily so i cleaned it with contact cleaner and cleared the code but that didn't help and the code came straight back after a drive. I've also read that this code can be related to DPF delete, but i also see there is a fair amount of oil on the intake piping especially above and below that sensor so maybe i need to look at the charge pipe seals, who knows it could be a number of things but i think ill come back to this later on as other leak issues may be related...
 
 
I've found the seals that come with the swirl kits are crap and now throw them away. I buy Elring seals and fit the blanks with instant gasket as they also leak after a year. 4mm id pipe doesn't have enough grip as the fittings are 4mm bits that's my opinion

Sent from my SM-G920F using Tapatalk

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Gonzo, it sounds like you have some great experience so i think i'll take your recommendation, that's some great info there and sounds like i should prepare to replace those seals too as i don't want to repeat the work.

 

Could you just recommend how much hose per colour?

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Replaced all vacuum hoses today, wasn't too bad of a job, used just over 2m of black silicone hose, and just over 1m of red and blue each so definitely could have got away with ordering less.

 

Inlet manifold was not as bad as i was expecting and its now soaking in some mr muscle oven cleaner (2 cans) its been soaking for an hour now and most of the hard crud hasn't shifted yet although there is a pool of black goo forming in the bottom of the container I've put it in, going to leave it overnight but im not convinced its going to clean up as well as i'd like it to. Some of the el cheapo seals were definitely leaking so glad i got the elring set, also slight tear in the shutter valve gasket but i think it will be ok, if not its an easy fix really...

 

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Got all the blanks out and cleaned them up ready for some instant gasket.

 

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Only issue i have is i dropped my torx bit adapter somewhere in the bay, spent a while trying to find it fishing around with a torch and magnetic pick up tool but no joy yet, hopefully find it tomorrow before it all goes back together.

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Probably nobody cares but ill update anyway, inlet manifold is not as clean as id hoped, still lots of crusty build up in there but i think at some point ill revisit this with a bath in kilo of caustic soda. That aside, its all back together with new Elring seals, also used some instant gasket on the blanks, everything torqued up to spec and no bolts left over. 

 

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Just cleared the codes and took it for a drive and all the power is back, re-read codes and its all clear now including 41AB :D

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Glad it's all sorted, I wouldn't bother revisiting it m8, it's quite clean considering some of the ones I have seen!

Just be glad it wasn't an N47 one, they're horrible.

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Just a tip if anybody else is doing the vacuum hoses. I bought a ram airs 4mm id silicone hoses and few 4mm id T adapters with them for a good fit. 

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Hey guys, the code 41AB keeps coming back, i suspected the charge pipe seals needed doing as there was oil mist and grime all over the pipes and intercooler so I've cleaned it all up and replaced the 3 seals shown in part number 3 here:

 

https://www.realoem.com/bmw/enUS/showparts?id=NC92-EUR-01-2005-E60-BMW-535d&diagId=11_3789

 

This is how they compared, you can clearly see how much the seal has shrunk, when i took the elbow off the intake it just slid off no problem but it took me about 20 mins and a lot of swearing to get the new one in place so a massive difference there, the two where the pipes connect to the intercooler where pretty easy though.

 

mvAWWwc.jpg

 

I didn't replace seal part number 2 as there wasn't anything leaking that i could see, it all looked relatively clean looking from underneath...

 

I reset the codes and took it for a drive, came back and the code has returned again, anyone have any more ideas on what could be causing this before i just go and fork out for a new sensor part number 10?

Edited by max535

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Just looking a bit deeper into this with INPA

 

3HiHmJj.png

 

B8aAj4Z.png

 

Struggling with the language barrier here but if anyone is used to looking at these diagnostics and has any insight that would be appreciated, i assume its basically just saying its not seeing the boost pressure its expecting?

 

I have also just been out to have a look and it appears im still getting some sort of oil mist dripping down from between the intake elbow and metal part of the charge pipe, so having disconnected the top hose (which is now all greasy again) there appears to be a number of scratch marks and small slashes on the underside of the pipe, none of which appear to have gone through but maybe the pressure is still leaking through. I suspect someone may have caused this in the process of deleting the EGR...

 

I'm thinking replace the top hose first and see what that does, anyone got a good known used one knocking about, or maybe i should go straight to a new one or aftermarket silicone hose?

Edited by max535

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Hi. Do you still have all power even with that code? My e60 530d had 41aa code all the time,but that didnt affect its performance and been told that it because of gutted dpf and remap,so it never bothered me. If yours is running at full power,then just dont bother.

These engines allways have oil in the intake and around intake pipes,even after seals replaced it might.be getting oily anyway,so probably need to live with that or another option is fork out for brand new genuine piping,maybe intercoller and then should be dry for a bit.:D

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Its still making plenty of power but it really bugs me, i have managed to get this car from having something in the region of 10 codes to only 3, one is for aux water pump (dont care), another for the most gateway (possibly because i replaced bluetooth and tv module without coding the vin) and finally this 41AB, if that is going to affect power in any way at all i want to sort it as plans are to get it mapped since the car already has egr delete, swirl flap delete and dpf delete with 3 inch downpipe. I may even replace the intercooler for a bigger stepped one since its such an easy job.

 

I'm fine with a bit of oil in the intake, that's to be expected, but if oil is making its way out of the charge pipes then surely a small amount of boost is being lost too... i don't think the intercooler is at fault, that seems unlikely and just replacing it feels like blindly throwing money at the problem.

 

So for now I've just cleaned everything up and done up the jubilee clips a bit tighter with a ratchet rather than a screwdriver so i think if the top hose turns all greasy again within the next few days and there is no other obvious source i think its pretty likely the hose needs to be replaced, like i said there are slash marks on the bottom of it so that damage points to the possible cause in my mind.

Edited by max535

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What i learnt from owning one of those is you need to learn to live with some small problems,like that 41ab code,because if that does not affect performance. By chasing those you might not gain nothing,just waste money. If thats been mapped than it might just see more boost or something at some revs or something.

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I think the 41AB code comes from the pressure sensor that connects to the exhaust pipe. It's the pressure sensor beside the vacuum reservoir in the middle left hand side of the intake manifold (left as you look at the engine from the front of the car). The sensor has a foil wrapped pipe going down to the cat.

 

If that pipe has a leak it could be your problem. The pipe could be blocked. The sensor duff, or it's just because you have a DPF delete.

 

You have at least 3 pressure sensors on the car. There's an ambient pressure sensor in the DDE itself. There's the MAP sensor and there's this sensor.

 

With just the ignition on (engine not running) all sensors should read roughly the same - ambient air pressure. If one does not then you get a 41AA or 41AB code.

 

With the engine running there are various plausibility checks, for example the manifold pressure is higher than ambient and that there is some exhaust back pressure. If something isn't right you can get a 41AB code. So it might just be the DPF delete.

 

I had a code that might have been 41AB (I can't remember exactly) after seriously cleaning my DPF and disabling the exhaust pipe flap. What happened was my exhaust back pressure at idle was reading 0 millibar and that was considered a fault. To fix it I reconnected the exhaust flap, the sensor read something like 5 millibars and all was well.

 

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On 30/07/2020 at 14:19, max535 said:

Just looking a bit deeper into this with INPA

 

3HiHmJj.png

 

B8aAj4Z.png

 

Struggling with the language barrier here but if anyone is used to looking at these diagnostics and has any insight that would be appreciated, i assume its basically just saying its not seeing the boost pressure its expecting?

 

I have also just been out to have a look and it appears im still getting some sort of oil mist dripping down from between the intake elbow and metal part of the charge pipe, so having disconnected the top hose (which is now all greasy again) there appears to be a number of scratch marks and small slashes on the underside of the pipe, none of which appear to have gone through but maybe the pressure is still leaking through. I suspect someone may have caused this in the process of deleting the EGR...

 

I'm thinking replace the top hose first and see what that does, anyone got a good known used one knocking about, or maybe i should go straight to a new one or aftermarket silicone hose?

 

That code is for boost pressure sensor on the intake manifold. "Ladedruck Istwert" = "boost pressure actual value" and that is logged on both cases below 500 mbar being way below static atmospheric pressure which is not plausible.

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48 minutes ago, Clavurion said:

 

That code is for boost pressure sensor on the intake manifold. "Ladedruck Istwert" = "boost pressure actual value" and that is logged on both cases below 500 mbar being way below static atmospheric pressure which is not plausible.


Thanks for that mate very much appreciated!

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A little more troubleshooting today, re-seated the sensor and plug and checked the codes again, but same issue is present as above with all similar values.

 

Unplugged sensor and fired her up, no immediate issues apparent, checked the codes again and now I'm getting code 3F01 (boost pressure sensor no signal) and 41AB again, although actual pressure value has now dropped significantly to only 118.5 mbar which is around 1.7psi (basically no pressure) that seems to align with no signal and i wonder if the reading of 118.5 mbar is perhaps a default number...?

 

So it seems to me the car is getting a signal from the MAP sensor only it appears to be lying, i think I'm fairly confident that i need a new genuine sensor on this one so will probably order it later tonight.

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Hi. Do you still have all power even with that code? My e60 530d had 41aa code all the time,but that didnt affect its performance and been told that it because of gutted dpf and remap,so it never bothered me. If yours is running at full power,then just dont bother.

These engines allways have oil in the intake and around intake pipes,even after seals replaced it might.be getting oily anyway,so probably need to live with that or another option is fork out for brand new genuine piping,maybe intercoller and then should be dry for a bit.:D

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Hi. I should have a second hand one somewhere that was working,but i replaced it with new genuine one and still was getting 41aa code. I think that 530d in 535d use same one. 

I cand give it away for free just postage.

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10 hours ago, Yuri84 said:

Hi. I should have a second hand one somewhere that was working,but i replaced it with new genuine one and still was getting 41aa code. I think that 530d in 535d use same one. 

I cand give it away for free just postage.

 

I've already put an order in and to be honest id rather a new one, thanks for the offer though.

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Well... new MAP sensor turned up so I just went out and fitted it and cleared the code again, took her out for a drive and floored it through a few gears in sport and guess what... no more code! B)

 

It may be too early to tell but every time I think i may have fixed it I've took her out for a blast and come back to find the same code again, it may be placebo but i could swear she runs better now, better pickup from low down and just overall smoother now through the revs and gears changes, feeling kinda smug right now :lol:

Edited by max535

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