Can anyone help me diagnose my car

Year and model E46?
How can we help you if you do not mention that?

 

Oops sorry! It’s e46 touring 2002 320d 5spd

 

not trying to be an ass, but when I post codes, I post codes like "mass air sensor faulty". I find it kinda difficult diagnosing someone's car by "3f01". I have no clue what this might be.

 

3F01 - DDE - charge air pressure sensor
3F03 - DDE - charge air pressure sensor
4063 - DDE - atmospheric pressure sensor (fitted in control unit)
4530 - Charge-air pressure control

I get these codes, I’ve cleared them now and 3f01 remains and can’t be cleared. Once I take it out for a drive it’s weak on power and doesn’t boost as well as it used to the engine knock is horrendous too at high revs and smokes badly out the back of the car when it’s making this diesel knock, at low rpm and steady speeds you wouldn’t think anything wrong with the car

 

maybe a silly one, but have you checked the IC tubing? Charge air pressure in combination with smoke and loss of power could be a boost leak.

 

Is that all the vac lines going from the turbo ? I replaced two of them from the wastegate. Does this look normal to you ? I always imagined that the boost pressure inside the manifold would equal if not higher than atmospheric

 

with a petrol engine this could be normal, as the throttle valve is closed so there's a vacuum inside the intake manifold, but the diesel engines don't have a throttle valve so the pressure should be equal or higher (boost) than the ambiant pressure. So as far as I can tell your sensor isn't operating correctly.

 

Thank you for clarifying this I spent ages trying to makes sure this was the case, diverging into the problem more I have worked out that before it went to a constant showing of the fault codes it would appear at 2511mbar my sensor I have only goes to 2500mbar and as my car has been tuned by a bmw specialist to produce 210 HP I suspect it requires more boost and has therefore buggered this sensor. I’ve ordered a 3 bar sensor and perhaps it will sort out the issues

 

+- 1 bar is atmo pressure. So when idling this should be your actual pressure. Under load it should be +- 1,5 with stock engine. I have no idea how far boost goes on diesel engines when tuned, but I would say anything over 2 bar is not with stock turbo. Has your turbo been replaced? If not, 2,5 bar seems like a lot and I would doubt the pressure sensor once again.

Don't take my word for it, these are just assumptions. I had an M47 but it was bone stock.

 

I haven’t owned the car long. I bought as a project back in august it had been parked for 2 years with an “reconditioned turbo” and then tuned by the bmw specialists of who I’ve heard from. Originally the car would stall at idle and drove horrendous, turned out to be two injectors which I replaced which sorted out the rough idle however the issue I have now has been consistent from the start soon as you’re putting the foot down and asking for torque it’s coughs and splutters, I’ll fit the new 3 bar sensor and see what happens when it arrives. That would mean it would boost 1.5+ including the atmospheric pressure. I have a friend with s remapped n47 from the 520d e60 with boosts 1.7 bar (2.7MAP) And makes 220HP so I suspect them to similar but time will tell.

 

UPDATE - new map sensor arrived today, the brand is RIDEX from AutoDoc cost me £18 which is cheap but wanted to see whether there’s a difference, checked the live, ground and signal on the plug all working correctly and fitted the new sensor, which is the second one I’ve bought for the car, immediately for the correct reading for atmospheric/ambient (1000)mbar and 1100/1200 MAP mbar

took it for a drive and all responds better and couldn’t get an engine knock till 4700rpm, the code has now changed to (3F00 - manifold pressure sensor) Which is different to the others I had.
It’s strange as on my scanner I’m still reaching 2511mbar which would be 1.5 bar of boost, it levels off here and won’t climb any further even though the car is still gaining power/boost. I know my sensor I’ve bought reads up to 3bar so I find this strange.
The code is intermittent and only happens when I get the engine knock at high RPM I’m thinking I might have a boost leak ?


hard to explain the noise but under high load I get the vibrating air sort of noise like a flag blowing in strong winds as boost reaches 2511mbar
More diagnosing needed but definitely getting somewhere

 

Ok so 3f00 means short circuit to B+ does anyone know what that means ?
My previous

code 3f01 - meant short circuit to B- open
And 3f03 - meant boost sensor plausibility.
So what does short circuit to B+ mean?