Misfire Cylinder 1,2,5

[Sammyzuko]

Need some help with this. Only codes are the misfires on cylinder 1,2 & 5. Engine barely runs/idles. If I rev it there is a sucking sound from near the intake manifold. At idle it sounds a bit like a chugging train in that same area.
Things I've tried:

• Fresh tank of gas with fuel additive.
• Replaced fuel filter.
• Cleaned the MAF. Runs about the same with MAF disconnected.
• Smoke test...no smoke visibly leaking.

If it was something like the crank position sensor or O2 sensors I would think there would be codes for them

Edit: Added a couple videos. Second vid is giving it light revs.

https://www.youtube.com/watch?v=cnWi...ature=youtu.be
https://www.youtube.com/watch?v=2j5o...ature=youtu.be

[Hova]

Check for vacuum leaks.

Also does removing the oil cap make any difference in the way it idles?

[Sammyzuko]

Check for vacuum leaks.

Also does removing the oil cap make any difference in the way it idles?

Smoke test didn't find any obvious leaks. Wonder if it could be something like a cracked hose that only splits apart when the engine is running/shaking.

I removed the oil cap a few times....it either makes the idle dip then recover or the engine dies.

[UsernaM3]

Smoke test didn't find any obvious leaks. Wonder if it could be something like a cracked hose that only splits apart when the engine is running/shaking.

I removed the oil cap a few times....it either makes the idle dip then recover or the engine dies.

Any updates here? I went through the electrical diagram just to see if those cylinders are linked at all but they are unfortunately not all linked anywhere that I could find.

[Sammyzuko]

Any updates here? I went through the electrical diagram just to see if those cylinders are linked at all but they are unfortunately not all linked anywhere that I could find.

Thanks for the info....I haven't been able to find anything that would link those cylinders. I'm not sure what to check next without taking off the manifold, and to be honest I'd rather just pay my local shop that knows these cars well than start randomly pulling things apart. The forum was my last effort to see if there's something fairly simple I'm overlooking.

[das borgen]

Check that spark is good? Pull the spark plugs on those bad cylinders and then pull the fuel pump fuse and crank the engine in these 2 scenarios:
1) ground them each, one after the other (touch the body of the plug to a metal part of the frame or engine while the coilpack is plugged to see if the coil or the plug is bad
2) If any of those aren't firing, try a separate known good spark plug (brand new one) with each of those coilpacks to see if the coilpacks are firing OK

I recommend a helper to crank the engine for you while you observe for spark in each of those tests.

If your codes are just isolated to those 3 cylinders, it's likely spark-related, but it could very well be fueling. I agree with you about other sensors since they would be explicitly called out by codes from your engine scan tool

[Sammyzuko]

Check that spark is good? Pull the spark plugs on those bad cylinders and then pull the fuel pump fuse and crank the engine in these 2 scenarios:
1) ground them each, one after the other (touch the body of the plug to a metal part of the frame or engine while the coilpack is plugged to see if the coil or the plug is bad
2) If any of those aren't firing, try a separate known good spark plug (brand new one) with each of those coilpacks to see if the coilpacks are firing OK

I recommend a helper to crank the engine for you while you observe for spark in each of those tests.

If your codes are just isolated to those 3 cylinders, it's likely spark-related, but it could very well be fueling. I agree with you about other sensors since they would be explicitly called out by codes from your engine scan tool

Thanks for the advice. I forgot to mention I replaced the spark plugs. I'll check spark/coilpacks like you suggested.

[ScotcH]

It's likely a coil ... 2 or 5 probably, they are linked in the codes as the pistons are in same position. Just pull each coil plug as it's running. If you don't hear it change sound, you found your dead coil. Swap with another coil to make sure, and if the problem follow the coil, replace. If it does NOT follow the problem (ie, same cylinder even with different coil), you might have an injector issue.

[AJLM34A]

Need some help with this. Only codes are the misfires on cylinder 1,2 & 5. Engine barely runs/idles. If I rev it there is a sucking sound from near the intake manifold. At idle it sounds a bit like a chugging train in that same area.
Things I've tried:

• Fresh tank of gas with fuel additive.
• Replaced fuel filter.
• Cleaned the MAF. Runs about the same with MAF disconnected.
• Smoke test...no smoke visibly leaking.

If it was something like the crank position sensor or O2 sensors I would think there would be codes for them

Edit: Added a couple videos. Second vid is giving it light revs.

https://www.youtube.com/watch?v=cnWi...ature=youtu.be
https://www.youtube.com/watch?v=2j5o...ature=youtu.be

What part of the intake did you use for the smoke test? I would pull the breather tube from the valve cover the air/oil separator and insert the smoke test tube into the breather tube.

[Sammyzuko]

I appreciate all of the replies.
Smoke test was connected to the Bimmerworld intake boot.
I just disconnected ignition coils one at a time with the engine running. No change in engine rpm when disconnecting coil 1 & 2. All of the rest (including 5) made the engine struggle. Maybe I was decoding the codes incorrectly. Codes are 11 F2 EE EF
I swapped coils 1 & 2 with 3 & 4. Retested disconnecting one at a time and same result, no change when disconnecting 1 & 2.
Looking into how to check the injectors...

edit: just swapped spark plugs 1 & 2 with 3 & 4, no change

[Braymond141]

I appreciate all of the replies.
Smoke test was connected to the Bimmerworld intake boot.
I just disconnected ignition coils one at a time with the engine running. No change in engine rpm when disconnecting coil 1 & 2. All of the rest (including 5) made the engine struggle. Maybe I was decoding the codes incorrectly. Codes are 11 F2 EE EF
I swapped coils 1 & 2 with 3 & 4. Retested disconnecting one at a time and same result, no change when disconnecting 1 & 2.
Looking into how to check the injectors...

edit: just swapped spark plugs 1 & 2 with 3 & 4, no change

Confirm the coil pack harness plug is fully seated.
Confirm the injector power rail is fully seated into each injector.
Check the ECU connector for any corrosion. Also confirm the connector is properly seated and after seating you firmly push it straight in. Sometimes they don't fully seat using the lever.

[ScotcH]

Was this engine running fine before? Was is $shifted (bent valves)? A bad HG failure between cyl 1/2 could cause no fire as well ... if everything else (electrical, fuel) checks out, a compression test would be next step.

[Sammyzuko]

Confirm the coil pack harness plug is fully seated.
Confirm the injector power rail is fully seated into each injector.
Check the ECU connector for any corrosion. Also confirm the connector is properly seated and after seating you firmly push it straight in. Sometimes they don't fully seat using the lever.

Thanks, I'll check those areas

Was this engine running fine before? Was is $shifted (bent valves)? A bad HG failure between cyl 1/2 could cause no fire as well ... if everything else (electrical, fuel) checks out, a compression test would be next step.

I was returning from a spirited drive when it started misfiring. Some high revs, but definitely no $ shift. Hoping this isn't too serious

[Sammyzuko]

Turns out the head gasket failed between cylinder 1 & 2.

[das borgen]

Yep. Your symptoms are pretty reminiscent of mine last when I discovered ultimately that mine was bowon between 4 and 5

[Sammyzuko]

Yep. Your symptoms are pretty reminiscent of mine last when I discovered ultimately that mine was bowon between 4 and 5

Any idea what caused yours to go?

[das borgen]

I don't know for sure, but my theory is that I had nicked it when I had done the head gasket previously myself 3 years ago when I was placing the head.

When I did it last year, the head gasket was completely blown between 4 and 5 and completely OK between all the water and oil jackets, and cylinder bores. My head was also warped by a decent amount 0.007" (service limit is 0.011")

Check my thread here from last year

https://www.bimmerforums.com/forum/s...Something-else