If you own a BMW with an N54 engine, you may have heard of the issue where the injector bores become loose. In this post, I'll explain what that means, why it happens, and how to fix it with the PPI injector bore repair kit.
If you didn't know, the injector bore is the hole in the head of the engine where the fuel injector sits. And if it becomes loose, that means the injector isn’t getting a proper seal to the engine. This can cause a number of problems including misfires, rough idling, and poor performance due to lost compression. And if left unfixed, it will continue to get worse and eventually make your BMW undrivable.
So why does it happen? Well, it's often due to improper injector installation or removal. With these cars being notorious for bad injectors, it’s not uncommon for them to be replaced (albeit improperly). If they were pulled side-to-side while being removed, instead of being pulled up with the proper tool, you can immediately oval out the bore. Fortunately, it can be fixed.
If you catch the damage early like I did, you can fix the bore without replacing the entire head, which can be a very expensive repair upwards of $12,000! The fix I showed in the video above requires a $500 kit from PPI and some patience. It involves rethreading the injector bore and installing a new insert to securely hold the injector in place.
I show every step you'll need to do in the video above, and in my experience, it worked flawlessly. The bores were actually tighter than they were from the factory, the injectors fit so snug I had to use a bit of force... but no more issues!
I've tried the teflon tape and copper washer, but neither worked for me long-term. This is the only proper way to fix this issue.
If you didn't know, the injector bore is the hole in the head of the engine where the fuel injector sits. And if it becomes loose, that means the injector isn’t getting a proper seal to the engine. This can cause a number of problems including misfires, rough idling, and poor performance due to lost compression. And if left unfixed, it will continue to get worse and eventually make your BMW undrivable.
So why does it happen? Well, it's often due to improper injector installation or removal. With these cars being notorious for bad injectors, it’s not uncommon for them to be replaced (albeit improperly). If they were pulled side-to-side while being removed, instead of being pulled up with the proper tool, you can immediately oval out the bore. Fortunately, it can be fixed.
If you catch the damage early like I did, you can fix the bore without replacing the entire head, which can be a very expensive repair upwards of $12,000! The fix I showed in the video above requires a $500 kit from PPI and some patience. It involves rethreading the injector bore and installing a new insert to securely hold the injector in place.
I show every step you'll need to do in the video above, and in my experience, it worked flawlessly. The bores were actually tighter than they were from the factory, the injectors fit so snug I had to use a bit of force... but no more issues!
I've tried the teflon tape and copper washer, but neither worked for me long-term. This is the only proper way to fix this issue.