2005 E53 4.4i N62 Misfire Help!

[kamhoe]

Originally Posted by stiubhartach

While injectors can cause lean misfire, the ECM will usually adjust by advancing the timing to prevent detonation.

Your problems sound more likely to be ignition related than fuel.

Since you replaced the plugs and the coils, the most likely culprit is the unseating of the coils.

From the Bosch website. More at the link:

“With the newly-designed coil, the customary “snap” is no longer heard nor is it an indication that the coil has been properly installed. This new design does, however, provide better coil performance at the spark plug connection point, which was the area that concerned some technicians. In other words, the original design actually gripped the spark plug tip and felt more secure; whereas the new design uses a contact spring on the spark plug tip and this design may not feel like the connector is gripping the spark plug – but in reality it does the job just as well or better than the old design.”

https://www.boschautoparts.com/en/au...ignition-coils

Originally Posted by stiubhartach

I actually just did all eight of mine yesterday, and initially had misfires on 1,2, and 7. Had to reseat them.

Pull the coils on the affected cylinders, lubed the TOP rubber boot with light silicon spray (NOT the plug boot!). Reseat them, twisting and ensuring the top seal sets down fully against the head. Make sure they’re all the way seated before you plug-in the connector socket and flip down the hold down.

Clear the codes, then start the car. Check for cylinder misfire codes. Reseat any cylinders that are still misfiring. Repeat until it’s clean.

Note:
1. Don’t use dielectric grease. It causes the coils to lift.
2. Do use DeOxit on the connector contacts if you’re worried.
3. The plastic hold downs that bolt to the head don’t guarantee that the coil is seated.

Originally Posted by andrewwynn

I noticed the lack of snap when I did a couple coil swaps recently, but I did notice that the coil floated up a bit before tightened down combined with that the cylinder misfire disappeared. I would probably put some deoxit on future swaps nothing beats the stuff to improve connections

I went for ride for about 20-30 miles yesterday after adding the Lucas a day ago but it doesn't help much as the car still shaking like hell during stopping/idling.

I installed the newly-designed coils which is 0 221 504 464.

When you said adding silicon lube to the top rubber boot, are you referring to the Part D (attached pic)?

I've seen people adding something paste (can't remember what was that!) to the hole of Part A on YouTube. Does that help or necessary too?

I though about my BMW scanner 1.4 that I used years ago. Does the scanner able to tell if the problem related to ignition or fuel injector?