new plugs and coils and now car won't start.

[Dean Freeman]

The basics. 2006 325i, 157,111 miles, regular scheduled maintenance done, new starter 2 months ago.
So, I park at the grocery store and just as I am to turn off the car, I get a cylinder 5 misfire warning. I turn off the car get my groceries thinking it was just a quirk thing but it happens again and I limp the 1 mile home. I get on the site here to see what's up and what to do. Simple answer was, change the spark plugs so I did. I got 6 NGK 1208 laser iridium and installed per instructions, I did use a torque wrench. Incidentally, the plugs had been changed at 100,000 mi by the dealership but the coils were not. Started the car and got the same cylinder 5 misfire and car ran rough as before. Next step was to replace the coils which I did, Bosch 0221504470. Neither the plugs nor the coils showed any signs of fouling - no oil - just some wear. Now the car will not start, it seems to get very close but nothing. Not sure what to do next except have it towed to the shop. I thought this would be an easy fix. Before this event the car had been running flawlessly, except I did have the dealership replace the valve cover because they said it was showing signs of cracks and it would eventually fail on me. Suggestions?

[patton001]

How did the plugs look? Where any of them wet? Do you have a code reader? Do you have a fuel pressure gauge? Make sure all of the coils are fully seated..

[White94RX]

I'm guessing the new coils aren't plugged in all the way. The new coils takes quite a bit of force, or rocking back and forth to get the connector to go all the way in.

[jclausen]

Always recheck your work, if everything was fine before you started or you fuel pump just died, which is what happens when they die,,no warning.

[dday1991]

I installed new ignition coils this morning as preventive maintenance. (BMW Direct Ignition Coil - Bosch 0221504470) same as you. Car wouldn't start. I put the old ones in an it started right back up.

[White94RX]

You didn't push the connector all the way into the new coils.

[rbelton]

Old thread, but this DIY demonstrates correct installation on an N54 (same procedure on the N52): https://youtu.be/27tdDLk2IQ8