Various cylinder misfires

[Kcdoyle]

Hello Board, sure could use your help on this one.

Left my 2013 N55 135i idling at a slight angle, nose up, low fuel, in an effort to get car up to operating temp after I changed out the coolant reservoir and kept getting a low coolant alert. Purged it etc. All of a sudden it goes into limp mode and I get “misfires” on about every cylinder. Do my homework and it seems that at 91,xxx miles it’s might need plugs, coils, etc. Changed all the plugs and all the coils. Zr5tpp33 plugs. restart and runs fine for about a minute and bang, limp mode again. And again. Start researching what could be next, Camshaft sensor, crankshaft sensor, Vanos replacement etc. I have found many DIY’s on the Vanos replacement but I cannot for the life of me find a DIY on the camshaft sensors. Again the only codes I’m getting are misfires. No Vanos codes etc. I also have that radiator looking yellow warning graphic and a “low coolant” alert but nothing when I pull the codes.

Any thoughts?

Also, I did not check the gap on these plugs as the articles I read said they came pre gapped. I just looked and the box and it says .032. I believe our plugs are supposed to be gapped to .022. Can this cause the misfires?

[Kcdoyle]

Originally Posted by Kcdoyle

Hello Board, sure could use your help on this one.

Left my 2013 N55 135i idling at a slight angle, nose up, low fuel, in an effort to get car up to operating temp after I changed out the coolant reservoir and kept getting a low coolant alert. Purged it etc. All of a sudden it goes into limp mode and I get “misfires” on about every cylinder. Do my homework and it seems that at 91,xxx miles it’s might need plugs, coils, etc. Changed all the plugs and all the coils. Zr5tpp33 plugs. restart and runs fine for about a minute and bang, limp mode again. And again. Start researching what could be next, Camshaft sensor, crankshaft sensor, Vanos replacement etc. I have found many DIY’s on the Vanos replacement but I cannot for the life of me find a DIY on the camshaft sensors. Again the only codes I’m getting are misfires. No Vanos codes etc. I also have that radiator looking yellow warning graphic and a “low coolant” alert but nothing when I pull the codes.

Any thoughts?

Also, I did not check the gap on these plugs as the articles I read said they came pre gapped. I just looked and the box and it says .032. I believe our plugs are supposed to be gapped to .022. Can this cause the misfires?

So…I pulled the coils and plugs, regapped them to .022 and still was getting multiple misfires on 3 cylinders, 2,5,and 6. Decided to clear the codes again, only this time I decided to not let it idle. As soon as it turned over I got my foot on the pedal and keep it between 2500 rpm and 3500 rpm. Here is where it got interesting; the car was still throwing misfire codes, but DID NOT go into limp mode. I cleared the codes and keeping the engine revved, hit the highway for the ole Italian valve job. Made a pretty heated 2 mile run, got back to the house and voilà! Not a single code. Perhaps I cleared a dirty injector or 2 but I can tell she is much peppier and idle sounds great. FWIW if this keeps happening to you.