Hi everyone,
I have leakage from cylinder #1 and #4 on my engine. The engine has almost 120K miles.
Both local mechanic and official dealership told me that all 4 injectors should be replaced due to mileage. And the price is huge higher than my car value.
After some research and Reddit post I decided to replace the two copper seals by myself, but I afraid to mess it up.
Here some YouTube video I have watched
https://youtu.be/d5vNLuEuX-I?si=_K8_jZwvZTFlUqen

The parts I found on jagbits.com

Here are my questions:
1) what materials/degreases should I use in order to clean the carbon buildup?
2) Should I use anything to loose the bolt? I afraid to break it during opening.
3) How should I clean the injector when there are out?
4) What is the torque value for the injector bolt?
5) In case I will discover broken injector, should I replace all 4? Does it require any calibration for the new injectors?

Thanks!

 

you need to pre-clean the openings in the valve cover where the injector and the injector clamp bolt passes deep inside.
your best bet is probably going to be a strong engine degreaser and a pressure washer to remove the debris, then use a compressor blow gun to finish cleaning out debris and leftover water from the pressure washer.
you cannot let the debris drop down in the threads of the bolt or on top of the pistons when the injector is removed.
there is a special injector wire brush used to clean the surface where the copper injector seal seats.

Yes, before removing the injector clamp bolt and the injector itself spray a Bolt Penetrating spraylubricant down in both holes to free up the bolt and lubricate for ease of removal.

you cannot clean them internally you can only clean off the carbon on the nozzle tips with a small brush and some carburetor cleaner.
you have to be very careful not to bump the tip of the injector, and not to scrape the very tip where the microscopic holes that inject the fuel are located. The injectors cannot be swapped to a different cylinder and must be reinstalled to the same cylinder. The return port, and fuel inlet Port should be capped to prevent debris from entering the injector. just a little debris can plug the nozzle.

it is not a torque value it's an angle degree (torque angle). you cannot reuse the injector bolts. they are one time use torque to yield or stretch bolts.
if you attempt to reuse them and use the angle in the specifications the bolt will most likely snap or loosen up over time.

it's not really possible for you to notice a broken injector visually. if when praying out the injector from the head the tip brakes off you are screwed, and most likely the head will have to come off to get the injector tip out of the port. The injector must be pulled straight upward. Don't allow it to tip side to side when pulling it out.

yes. each injector has a code on the body that is used to adjust the flow rate in the ECU when replacing with new injectors. if you run them on a test bench, clean them, and disassemble them for any type of repair they need to be re-coded on a Bosch fuel injector stand and re-programmed onto the car again. The injectors are JLR proprietary Bosch.

Note: I just went through this process recently and instead of replacing all of the injectors because I had a lower mileage, I took them to a fuel injection shop and had them flow tested, and pattern checked. they were all good and very equal flow. when they fail either some of the ports get plugged up and or the spray pattern is wrong, and or they over inject, under inject, or have too much leak back from the return port.

cautionary note: if your injectors have been leaking past the copper seal for a long time it can damage the head surface at the seal area. if this happens a special tool is needed to repair the surface before reinstalling the seals. basically compression blowing past the seal makes a little groove in the aluminum head. the compression will simply squeeze past and burn the new seal to the point of leaking again. also it is a good idea to anneal the copper seals before installing the injectors. When softening them up, they crushed and seal better the first time.

Cautionary note: the fuel injector metal lines are also one time use. They originally crushed and deform into the proper seating surface. The first time they are installed. If they haven't been reused before, and they're in good shape, you can reuse them and then just check for leaks to replace any line that does leak in the future. Do not torque them to the specification on the second time of use or you will damage the seal surface. The new torque spec is by hand (damn tight).

 

I really appreciate your very detailed response!

I got two bottles of Gunk engine degreaser spray and plan to use them to clean everything as much as I can. I’m a little worried about having to clean inside the bolt threads, so I’ll try to clean it as best as possible without going too deep into them.

got it, thanks!

Can I just use same engine degreaser and to clean it from outside?I found this really helpful video from a guy doing exactly the job I need to do: I was wondering where I can buy those injector hole covers, or what people usually use as an alternative to seal all the openings while cleaning.
Also, do you have a link for a decent but not too expensive metal brush for this kind of cleaning?
The video is cut a little, so I couldn’t fully understand — did he use the same brush both for cleaning the injector itself and for cleaning inside the injector hole?

I got 4 new bolts, but what is the correct torque angle specification? In the previous video, did he torque them to 10 Nm first and then do 2 × 90° turns?

Is there any special technique or tool for pulling the injector out straight?

I don't think anyone in my area has test bench, lets say worst case scenario I buy 4 new aftermarket injectors, theyprobably have some numbers on them so could i just update it to ECU, what tool shoul i use to interface with the ECU?




​​​​​​
​​​​​​​