BMW Forums : BimmerForums banner

1 - 20 of 117 Posts

·
Forum Chatbot
Joined
·
2,648 Posts
Discussion Starter #1
Hi

I only normally get a misfire when the engine is cold but when it was 18 degrees outside this morning I was surprised to get the misfire before I left the driveway. I had lean codes and sure enough I found dirt in the MAF sensor. Is this mix of misfire and lean together due to to anything serious I should look into? I'm going to clean the MAF later and see how it goes.
 

·
Forum Chatbot
Joined
·
2,648 Posts
Discussion Starter #2
Hi,

I have cleaned the MAF sensor twice with appropriate cleaner, used a small paintbrush to get the fly out. Anyway, after vacuuming the filter and putting it all back together, despite the engine being hot as I just drove home, it ticked over a while then went to P1347 Manufacturer Control. I have had this code before, this I mistakenly took for random misfire is actually misfire on cylinder 3 with fuel cut off.

I have done no work on my car at all and it drove perfectly fine home yesterday, I have some fuel trims info in the pictures. I have the ongoing catalytic converter below efficiency, which I treat every ow and then with fuel system cleaner. Any advice gratefully received.
DSC_1568.JPG
DSC_1569.JPG
DSC_1570.JPG
 

·
Forum Chatbot
Joined
·
2,648 Posts
Discussion Starter #5
I just had an idea so I disconnected the MAF sensor, went for a short drive, and when I set off the old paper flapping against the exhaust symptom was there pretty bad, the car sat on the driveway the last two hours so it cooled down a bit to the 10:30 position where 12 is running temperature. When I got back the flapping wasn't so bad but still there. I put the sensor back on, started the car and it took one minute of idle before it threw the code again. Looking at the notes I have on the car this code usually clears itself up. I have thrown in fuel system cleaner to see if it might be injector issue.
 

·
Registered
Joined
·
952 Posts
Sorry @iamthewalrus Your pics are honestly a bit disturbing! It looks like you have the diagnostic reader stuck between the cleft of your arsse?
But putting that behind us (no pun intended) can you not get INPA and the obd cable (and dis) these generic code readers are good at being generic! INPA is also not the perfect but at our level you can use it quite effectively.

shit in = shit out
 

·
Forum Chatbot
Joined
·
2,648 Posts
Discussion Starter #7
Sorry @iamthewalrus Your pics are honestly a bit disturbing! It looks like you have the diagnostic reader stuck between the cleft of your arsse?
But putting that behind us (no pun intended) can you not get INPA and the obd cable (and dis) these generic code readers are good at being generic! INPA is also not the perfect but at our level you can use it quite effectively.

shit in = shit out

I don't have inpa but I am concerned the fuel trims say zero?
 

·
Super Moderator
Joined
·
3,596 Posts
With M54 engine air/vacuum leak until other proven. Rubber boots between MAF and throttle valve, CCV, DISA valve and rubber plugs at the rear end of intake manifold.
 

·
Forum Chatbot
Joined
·
2,648 Posts
Discussion Starter #9
Hello Clavurion,

Thank you for your response.

Rubber boots between MAF and throttle valve
ok easy to check I will dismantle, check and clean tomorrow night.

CCV, DISA valve
CCV was replaced about 5 years ago. I personally cleaned and checked the disa valve about 3 years ago, I also cleaned the ICV.

rubber plugs at the rear end of intake manifold.
I don't know which part you are referring to?
Thanks in advance.
 

·
Forum Chatbot
Joined
·
2,648 Posts
Discussion Starter #10
Just thought, if I get the misfire with the MAF disconnected that's surely not a boot air leak issue?
 

·
Forum Chatbot
Joined
·
2,648 Posts
Discussion Starter #13 (Edited)
If one cylinder is cut off is it OK to do a 50 mile journey at the weekend up the motorway?

I have used the gas a lot lately, is it possible to get the car to use the cylinder for the purpose of helping to get injector cleaner through it?

How long do spark plugs last for, the ones that also do lpg?
 

·
Registered
Joined
·
421 Posts
You can drive on a misfire fine but you risk damaging the catalytic converter. Get anything, laptop with windows xp spend £20 on obd cable and inpa software.
 

·
Forum Chatbot
Joined
·
2,648 Posts
Discussion Starter #15

·
Registered
Joined
·
982 Posts
Yup it seems that one is upgraded version (with yellow switch). I have a old VAG adapter, had manually soldering a bridge to get work on E46.
 

·
Registered
Joined
·
105 Posts
Get inpa, it's much more understandable.
Well, sort of. except when it displays the messages in German.

I got a more expensive diagnostic tool and it did wonders and Autel 806 - but there are others and BMW specific ones too. I think there is a long thread on it somewhere on this site.
 

·
Registered
Joined
·
105 Posts
With M54 engine air/vacuum leak until other proven. Rubber boots between MAF and throttle valve, CCV, DISA valve and rubber plugs at the rear end of intake manifold.
Probably but perhaps also do the coil swap as well and see if the code moves from cyl 3 to the cyl you swapped with.

see if you can do a smoke test
 

·
Forum Chatbot
Joined
·
2,648 Posts
Discussion Starter #19
Yup it seems that one is upgraded version (with yellow switch). I have a old VAG adapter, had manually soldering a bridge to get work on E46.
OK thanks for letting me know, I've ordered it should get it Monday . Just wish I could do something in the mean time. Strange that the car run fine all week.
 

·
Forum Chatbot
Joined
·
2,648 Posts
Discussion Starter #20
I noticed a nasty vibration noise at 70 mph but it was not there at 60. Its like when you drive on the white stripes on the edge of the road.
 
1 - 20 of 117 Posts
Top