E46 330ci Active Exhaust Proble + Misfire
Discussion
Recently (Sat) bought an E46 330ci, 2002 with 88k
After a flawless 250 mile drive home from bristol and a day not doing much I took it out to go to work on monday and it developed a misfire under moderate acceleration, engine light came on and the car was running on 5, cycled the ignition after pulling over and it was fine, it then proceeded to do it a further 2-3 times over the next day and logged the code P1347 which relates to cylinder 3 misfire + fuel cutoff
Now being new to me and under warranty from the dealer I booked it into a local specialist today for diagnostics and they have found the same code (+ a faulty oil level sensor and o2 sensor heater!) but having switched the coil to cylinder 1 cannot cause it to misfire again...presumably all is well.
I know of the possible coil problems with these cars, but what seems strange is that when cycling the ignition everything restores itself (and if not run for long misfiring, clears the management light at the same time), would an intermittantly failing coil, plug or boot do this? or could it be something else (the engine was freshly steam cleaned when I collected the car, but as said ran fine on the way back)
I need to run it for the next few days and see what I get and take it back in if something reoccurs
_________________________________________________________________________________________________
The other problem I have is with the active exhaust system (butterfly valve in backbox), now the valve itself is free to move with my finger and the diaphram and actuator work OK, but there is no vaccum to the line...what is the likely culprit for this, the solenoid or something further up towards the engine?
I know a lot of people remove the pipe and block it off, but I want it working as I find it drones a little on the motorway, so I want to fix it...how is the line run up the car once it goes inside the boot? what do I need to test?
Regards
Matt
P.S
Other than the little niggles (which I am a tad worried about, particularly 4 days into ownership) the car is great, hugely powerful and smooth (when not missing).
After a flawless 250 mile drive home from bristol and a day not doing much I took it out to go to work on monday and it developed a misfire under moderate acceleration, engine light came on and the car was running on 5, cycled the ignition after pulling over and it was fine, it then proceeded to do it a further 2-3 times over the next day and logged the code P1347 which relates to cylinder 3 misfire + fuel cutoff
Now being new to me and under warranty from the dealer I booked it into a local specialist today for diagnostics and they have found the same code (+ a faulty oil level sensor and o2 sensor heater!) but having switched the coil to cylinder 1 cannot cause it to misfire again...presumably all is well.
I know of the possible coil problems with these cars, but what seems strange is that when cycling the ignition everything restores itself (and if not run for long misfiring, clears the management light at the same time), would an intermittantly failing coil, plug or boot do this? or could it be something else (the engine was freshly steam cleaned when I collected the car, but as said ran fine on the way back)
I need to run it for the next few days and see what I get and take it back in if something reoccurs
_________________________________________________________________________________________________
The other problem I have is with the active exhaust system (butterfly valve in backbox), now the valve itself is free to move with my finger and the diaphram and actuator work OK, but there is no vaccum to the line...what is the likely culprit for this, the solenoid or something further up towards the engine?
I know a lot of people remove the pipe and block it off, but I want it working as I find it drones a little on the motorway, so I want to fix it...how is the line run up the car once it goes inside the boot? what do I need to test?
Regards
Matt
P.S
Other than the little niggles (which I am a tad worried about, particularly 4 days into ownership) the car is great, hugely powerful and smooth (when not missing).
Thats a useful starting point yes, thank you
The mechanics have tested it today and there is no vaccum coming along the pipe where it joins the diaphram, although attach a vaccum to the pipe and the exhaust valve closes, pipes are supposedly in good condition too so It's definately further up the system
The Solenoid control unit is the first thing I need to check, does anyone know where this is located, and also the path the pipes go/where they start from (before the vaccum reservoir)
Thanks
The mechanics have tested it today and there is no vaccum coming along the pipe where it joins the diaphram, although attach a vaccum to the pipe and the exhaust valve closes, pipes are supposedly in good condition too so It's definately further up the system
The Solenoid control unit is the first thing I need to check, does anyone know where this is located, and also the path the pipes go/where they start from (before the vaccum reservoir)
Thanks
Pulled the solenoid out and that is the problem, vaccum goes in one end but not out the other, 12v to the connecter aswell so I am going to try a new solenoid.
Had the coils swapped round and on the way home from work tonight it started missing again, slightly different sensation though so im guessing the miss has moved to cylinder 1 but cannot confirm as the fault cleared itself after about 5 mins just as I pulled off the motorway, cleared the miss and the light aswell so it can't be serious if it can do that, just have to keep an eye on it.
Had the coils swapped round and on the way home from work tonight it started missing again, slightly different sensation though so im guessing the miss has moved to cylinder 1 but cannot confirm as the fault cleared itself after about 5 mins just as I pulled off the motorway, cleared the miss and the light aswell so it can't be serious if it can do that, just have to keep an eye on it.
- Update*
I have since tried replacing the exhaust solenoid (which sits behind the boot carpet) with a new one but to no avail, I have vaccum going in from the engine bay and 12v from the wiring plug, but the exhaust just stays open (valve free to move aswell)...if you connect the 2 pipes directly it closes so the vaccum is sufficient, but as soon as the solenoid is put into the line nothing happens
Has anyone come across this issue before, I thought I had found the problem but in light of the new solenoid I'm really a bit puzzled (particularly because it also has 12v at the connector)....I know most people block this valve open anyway but I cant stand the drone it causes.
The issue has been discussed here http://forums.bimmerforums.com/forum/showthread.ph..., with no definitive answer given other than that it may be a DMS grounding issue...any ideas
Regards
Matt
Edited by Matthew_Eames on Sunday 15th August 20:13
Bit of a strange question, but where did you get your new solenoid from and have you checked it's working? Reason I ask is I 'went through' 3 Approved Parts wiper motors from BMW before I got one that worked!!
Interesting regarding your misfire from the steam cleaning. Would it repeat itself if the car is left in the rain? I have had two incidents of the car misfiring which I thought was down to moisture, however after deliberately trying to induce the fault by leaving the car out in the overnight pouring rain a few weeks back, I couldn't get it to repeat itself. What brought you to the conclusion that it was the dealers steam cleaning that caused it?
Cheers,
Interesting regarding your misfire from the steam cleaning. Would it repeat itself if the car is left in the rain? I have had two incidents of the car misfiring which I thought was down to moisture, however after deliberately trying to induce the fault by leaving the car out in the overnight pouring rain a few weeks back, I couldn't get it to repeat itself. What brought you to the conclusion that it was the dealers steam cleaning that caused it?
Cheers,
BMW part, going to test it when I get a chance by using a 12v source, really wierd one...bit fed up with the E46 common probs, seems I have nearly all of them and am considering an A4 3.0TDi Quattro for load lugging (ski and bike carrying)...bit pricy mind.
The misfire was caused my moisture in the plug bores and around the coilpacks, swapped the coil onto another cyl and all is well at present.
The misfire was caused my moisture in the plug bores and around the coilpacks, swapped the coil onto another cyl and all is well at present.
Gassing Station | BMW General | Top of Page | What's New | My Stuff