BMW 325i 2005 misfire
- Thread starter danlightbulb
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I have a decent CTEK charger so it's on the car now, already reached step 3.
Exposed the battery in the car, the little clear window thingy is red on it as well.
There's nothing I can do but leave it overnight now I guess.
I'm struggling to believe that me having the doors open for a couple of hours could have caused this when it was starting fine yesterday (after having the misfiring on Thursday).
I hope it's not an ECU failure. The dash seemed to go wonky when I tried to start the car, it didn't even get one crank cycle in.
Exposed the battery in the car, the little clear window thingy is red on it as well.
There's nothing I can do but leave it overnight now I guess.
I'm struggling to believe that me having the doors open for a couple of hours could have caused this when it was starting fine yesterday (after having the misfiring on Thursday).
I hope it's not an ECU failure. The dash seemed to go wonky when I tried to start the car, it didn't even get one crank cycle in.
It won't be ECU failure - far more likely it's the battery which can cause all kinds of random issues when old/low.
I've had a battery die on me with no symptoms prior to it dying. It was proper dead as well.
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I've found a receipt for battery in the service history - April 2018 so 6 years ago.
A HAL battery, so presumably this means Halfords own brand.
A HAL battery, so presumably this means Halfords own brand.
If you can take it to Halfords I think they do free battery testing
@danlightbulb. Is it an N52 or N53 engine? I have the 330i with the N53 engine and caught a misfire.
I replaced spark plugs and coils with didn't cure it and discovered it was injectors which are quite pricey (and difficult to find) for the N53 engine.
My misfire, however was only at start up when the engine was cold and went away in a minute or so.
I would be replacing the battery though, as every one of the three BMW's I've had reacted badly to a degrading battery.
I replaced spark plugs and coils with didn't cure it and discovered it was injectors which are quite pricey (and difficult to find) for the N53 engine.
My misfire, however was only at start up when the engine was cold and went away in a minute or so.
I would be replacing the battery though, as every one of the three BMW's I've had reacted badly to a degrading battery.
its a N52 pre lci the N53 was plagued with the injector issues.
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16 months, bought off a friend when my previous car (Mondeo 2.5T) lunched it's engine. Full service history, regular oil changes etc, water pump done. The spark plugs were changed at the last service before I got the car.
I've since had the cam cover and oil housing gaskets replaced along with new bolts and the fan belt changed, transmission fluid changed with new filter pan, plus a service.
Yeah n52. The misfire happened on Thursday night a few minutes after starting the car. I could drive the car as long as I kept revs up a bit, it was spluttering at idle. I got home and it was still spluttering. Switched off, ignition off, and restarted and car was ok.
And ok yesterday when I started it whilst looking for fault codes and looking at the coolant (found level to be low, but not enough to trigger a warning).
If I can start it tomorrow after charging it, I will go get new battery (if I can drive it). If not, RAC call out.
Then if it appears to be driving ok I will get 6 new ignition coils.
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OK, it's likely to a one of a number of things.
VANOS solenoid
Fuel injector
Lambda probe
Coil pack
Vacuum leak
Bad MAF (unlikely)
You mentioned it can smoke a bit when cold so my money is on a vacuum leak allowing unmetered air in to the engine.
One thing you can do is disconnect the MAF (do this with the engine off). This will put the engine in to open-loop mode the next time its started. The idle will be higher but it should stop mis-firing. If it does stop then you can discount the coilpack and fuel injector as a possible fault.
Vacuum leak you can test for with a smoke test
Lambda probe will show up in the codes
VANOS solenoid you can test via substitution as they are easy to get to and are cheap.
VANOS solenoid
Fuel injector
Lambda probe
Coil pack
Vacuum leak
Bad MAF (unlikely)
You mentioned it can smoke a bit when cold so my money is on a vacuum leak allowing unmetered air in to the engine.
One thing you can do is disconnect the MAF (do this with the engine off). This will put the engine in to open-loop mode the next time its started. The idle will be higher but it should stop mis-firing. If it does stop then you can discount the coilpack and fuel injector as a possible fault.
Vacuum leak you can test for with a smoke test
Lambda probe will show up in the codes
VANOS solenoid you can test via substitution as they are easy to get to and are cheap.
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Thanks the thing is that it already stopped. It happened Thursday night and I was worried about switching the car off in case it would not restart, so I drove home with volatile revs, which was only problematic when idling.
Then when I got home I restarted the car properly and the misfire had gone.
Then Friday and Saturday I restarted the car and it was smooth. I did some maintenance on the car yesterday checking various things and today I cleaned it inside thoroughly. Then it wouldn't start at all so now it's being charged.
There were no codes other than the initial 6 misfire codes.
Seems unlikely to be an issue with all 6 coils. I wouldn't be replacing them just because, and on the basis of the codes you got on a single occassion
yes , of course it can't be all 6 coils ... & expensive to replace them all speculatively.
I'd still put money on the crank sensor I couldn't get a warm re-start for love or money and had to wait for it to cool, when mine was packing in.
conversely don't see the battery suddenly failing - when mine was weak, did find an hour listening to the radio whilst cleaning car drained it
... can you hear the starter relay clicking nonetheless.
I'd still put money on the crank sensor I couldn't get a warm re-start for love or money and had to wait for it to cool, when mine was packing in.
conversely don't see the battery suddenly failing - when mine was weak, did find an hour listening to the radio whilst cleaning car drained it
... can you hear the starter relay clicking nonetheless.
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Yes and the engine tried to turn for like half a second then nothing. Also dash has lost the time and date setting.
The car started normally yesterday. All I have done since then is replace one rear bulb, and clean and hoover the inside for a couple hours today.
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Most likely culprit is still the battery I think - could easily have caused the codes for the coils
That sounds like head gasket to me, leaking coolant into the cylinder overnight.
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It started. Phew I'm relieved.
Ctek charger had completed its cycle overnight and moved on to maintenance mode. Car fired straight up and drove normally.
So what to do now, get new battery anyway (6 years old)?
Honestly I'm just not sure. It's cold today (6 degrees) and on my test drive this morning there was some vapour coming out the exhaust. It's not billowing white smoke, just visible vapour that you can see from the mirrors whilst driving.
It has used around half a litre of coolant in six months I'm guessing, assuming they checked it properly when serviced which they might not have.