PPI BMW Injector Bore Repair Kit

PPI is proud to announce our patent pending injector bore repair kit for BMW engines. 

Please make sure to use the drop down menu and select your correct engine or we will ship a N54 kit by default. It is a different repair sleeve for each engine and a N55 kit will not interchange with a N54 kit. 

We have also added a repair shop starter kit as many of you shop owners have asked for. It will come with 16 sleeves and covers all engines listed in the drop down menu. 

Kits include ONLY the following, correct drill bit, correct tap matched to our sleeve, repair sleeves, drill guide, and an air hose to blow out combustion chamber to ensure no shavings made its way into the cylinder and if so, this will blow them out.

A customer made a nice DIY video which can be found here.

https://youtu.be/ajzUH0b71gQ

Disclaimer: this kit is to be used to fix a ovaled or worn out injector bore in the head as a chance to keep from having to replace the engine or cylinder head. This kit involves drilling and tapping the injector bore hole. By installing this kit you do so at your own risk. If you are not comfortable doing this we strongly advise having a shop do this. It is typically 1-2 hours labor time. 

Instructions: follow the below guide. 

PPI Injector Bore Install Guide

Professional Installation Instructions

1. Overview

This document provides a clean, structured, professional installation guide for installing PPI injector bore sleeves. All steps below reflect the manufacturer’s instructions exactly as provided and formatted for clarity and technician readability.

2. Required Materials & Items Not Included

Items Not Included (Must Be Purchased Separately):

• Permatex High Temperature PTFE Thread Sealant (592 or equivalent) Do NOT use a thread locker like Loctite! 

• New injector seals

• Injector seal compression tool (3-step type, commonly found on Amazon)

• Parts cleaner or brake cleaner spray

• Wheel bearing grease

• Shop air source (small air compressor is acceptable)

Recommended product link:

Permatex High Temperature 592 Thread Sealant (6ml Tube):

https://shop.advanceautoparts.com/p/permatex-high-temperature-592-thread-sealant-6ml-tube-59214/7010664-p

3. Safety Notes

• Wear safety glasses during all compressed-air operations.

• Ensure the engine is cool before beginning work.

• Rotate the engine by hand only when positioning pistons.

• Keep metal debris away from open engine components.

4. Installation Procedure

Step 1 — Position Piston at Bottom of Bore. Rotate engine by hand until the piston in the target cylinder is at the bottom of the bore. This provides clearance for drilling.

Step 2 — Drill the Injector Bore

Insert the supplied drill bit into the drill guide. Apply wheel bearing grease to the drill bit to capture metal shavings. Drill straight down using the guide. Remove the bit and clean off

grease and debris.

Step 3 — Move Piston to Top of Cylinder

Rotate the piston to the top of the cylinder. This ensures metal particles cannot fall downward during tapping.

Step 4 — Tap the Hole

Apply wheel bearing grease to the tap. Insert the tap through the drill guide and tap the bore while keeping alignment straight. When the tap suddenly becomes easy to turn, you have reached full depth. Back the tap out.

Step 5 — Clean Threads

Spray brake cleaner into the tapped injector bore to remove grease and debris.

Step 6 — Blow Out the Cylinder

Connect the supplied air hose to the spark plug hole of the cylinder. Blow compressed air into the cylinder. All remaining shavings will be forced out of the injector bore. Wear safety glasses.

Step 7 — Apply Thread Sealant

Apply PTFE high-temperature thread sealant ONLY to the first two threads of the repair sleeve. The sealant will distribute itself as the sleeve is threaded in.

Step 8 — Install the Sleeve (Do NOT Tighten)

Thread the sleeve into the tapped injector bore by hand. Turn clockwise lightly until it stops.

Do NOT tighten or torque the sleeve. Over-tightening may crush or deform the sleeve. When the sleeve stops turning, stop  do not tighten the sleeve!

Step 9 — Install Injector Seal

Install a new injector seal onto the injector. Use a proper 3-stage injector seal compression tool. Immediately install the injector into the newly installed sleeve.

Step 10 — Repeat as Needed

Repeat all steps for any additional cylinders requiring repair.

Post Installation Requirements

Allow 3 complete heat cycles before applying boost. A heat cycle consists of fully warming the engine to operating temperature and then allowing it to cool completely. This ensures proper seal seating.