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Spark plug DIY at 100k 745i

60K views 86 replies 44 participants last post by  dubz1981 
#1 ·
Changed the oil and did the spark plugs last weekend. Did not find a good writeup so I made one. I have a work document with photos. can I attach that?


Spark Plug change 2003 BMW 745i (E65)

I changed the oil first but taking the car off the ramps will make for better access. All the work is done from the top.

Tools needed:
Torx T30
Torx T25
Spark plug socket
10mm extended socket
2 3/8 drive extensions
Tape (trust me on this)
Wrench
Torque Wrench

Parts Needed:
8 new NGK spark plugs ($28 each at dealer, or under $2 each at Advance Auto)



Procedure:
Using the T30 torx screwdriver remove the four screws that hold the plastic engine cover to the top of the engine.


I also removed the plastic guards above the radiator fan for better access (T25)



I took this opportunity to vacuum the top of the engine and then used some compressed air to clean the dust and dirt off the engine. (do not do this with the spark plugs out!!!)

The next part that comes off is the “BMW” side covers. They will just pull straight out. They are held in by friction. No tools are needed for removal.

Now you will be looking at the coils on the spark plugs.




The coils should be removed one at a time. I started at the front and worked my way back to the firewall.
Below is a coil that has been removed.


Some of these are difficult to remove and will require some serious pulling. Rotate them back and forth to loosen the coils. Do not use any tools to pry the coils out. You do not want to break the harness clip.

The rear plugs (closest to the firewall) are a serious PITA. I needed to tape a few shorter 3/8 extensions together as I put them into the spark plug hole. Removing them I needed to cut the tape and remove each piece one at a time.


Below is the “tool” I made



Be sure to apply anti-seize on the threads before installing the new sparkplugs.
Torque the new sparkplugs in to 19 ft-lbs (or whatever the plugs state)

Push on the coil and be sure it “pops” back on. It will kind of click when it is on all the way. Clip on the harness and you are back in business.

Be sure to start the car before putting the covers back on the engine and take this time to reset the spark plug counter to 100k.
• Put the key in, do not put your foot on the brake
• Hit the start button
• Hold down the trip reset for 10 sec.
• Page through until you get to spark plugs and reset the value

My wife noticed MPG went from 24mpg to 25.6 mpg. Looks like the spark plugs were due! I changed them at 95k.
 
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#30 ·
No need to remove power steering fluid... The power steering reservoir has two nuts holding it in place. Once removed, you can lift the reservoir upwards (will take a bit of prying to get it over the bolt-ends) and then maneuver it out of the way so that you can get to plugs on the front-left side... You don't need to "remove" it, just let it sit off to the side.
 
#31 ·
i tried to change my plugs but was only able to change the first 3 on either side and the last 2 near the fire wall i couldn't get out. the coil itself when pulled upward was hitting my engine bay. i was like what the hec is this. so i only changed six and left the two rears.. which sucks.. i have an 03 745i and every1 seems to have changes all of theres successfully.. any suggestions fellas.. thanks.
 

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#34 · (Edited)
I guess the different model years might have less room...??? Mine definitely had very limited space (hence the 3 hours it took me!)

For the coils themselves, I had to pull at an angle pretty roughly especially on the ones at the very very back... it didn't seem like it was going to come out, but if you keep pulling it should... However, that's not the end of it... given the limited space at the back, getting the spark plugs themselves out is a challenge...

You should buy a U-joint adapter for your socket wrench along with different-sized extensions - this will allow you to bend your wrench at an angle (not going straight in)... I would say it's pretty much a requirement for getting the back ones out. And use tape wrapped around to hold all the adapters together - last thing you want is to lose an adapter in a spark hole at the back of your engine and then have to get creative on how to get it out)...

The second problem I had was my spark plug holes had some oil in them (will get around to changing the valve cover gaskets one of these days!) which caused the rubber boots around a couple of the coils to get stuck in the hole seemingly from suction on the back of the boot (the coil came out, but the rubber boot didn't with it). I put the finger of a rubber glove over the coil and stuck it in the hole and it gave it enough friction to pop the boot out.
 
#35 ·
I did this DIY early this afternoon on a 2004 745i. Took close to 3 hours. The tight space was definitely a challenge. The coil boot closest to the firewall on the drivers side took close to an hour of wiggling, twisting and sore fingers before it popped out. Thanks to the OP for the post. I too used NGK #BKR6EIX plugs. $6.99 each.
 
#36 ·
My videos showing how to get the difficult spark plug boots out, and pictures showing the general process --> here.
 
#39 ·
Thanks for the feedback guys!
 
 
#41 ·
spark plugs

I did my 02 745i about two weeks ago. I think it took about 45 min.. If you take the factory number of the original plugs you can get them at Kragen Auto for about $8.00 ea. Much better than the dealer. Also the back two cylinders you have to move the plug boots back and forth to wiggle them out. This is a very easy DIY job don't waste your money with the dealer.
 
#44 ·
Well, I just completed my 200k spark plug change. the coils were stuck on the plugs quite hard and I think I broke all my fingers removing them but they came out. since my $2 plugs lasted 100k without any issues and were giving ~23.5mpg I decided to replace them with the same NGK G-Power Platinum Alloy Spark plugs (BKR6EGP)
they were about $2.70 each this time.
There is no oil in the spark plug holes or on the plugs, great news for a car with 195k miles!

I also used two different spark plug sockets. one with a rubber insert for taking out the plugs and one without a rubber insert to put on the plugs. this eliminated the step using the tape because the socket would not get stuck after torquing down the spark plug.
 
#46 ·
What part are you getting hung up on? Pictures?
 
#47 ·
After removing the center cover from the top of the motor, which just pops off, I removed a back plate that gave me complete access to the top of the air intake. Which had numerous amount of Torx screws in it. After removing all these screws and trying to gently pry the top of this off I was concerned about proceeding because I did not want to damage anything. Did I miss something here? Should it be that difficult to change the plugs?
 
#48 ·
Yep, TIS does say that you have to remove the intake manifold to replace the spark plugs on the 760's...crazy. Looks like it's pretty straight forward after that.

The attached file is from TIS, and is for a 2004 760Li (N73 engine).
 
 

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#52 ·
here you go! post 1 of this thread had the info. ngk

Changed the oil and did the spark plugs last weekend. Did not find a good writeup so I made one. I have a work document with photos. can I attach that?

Spark Plug change 2003 BMW 745i (E65)

I changed the oil first but taking the car off the ramps will make for better access. All the work is done from the top.

Tools needed:
Torx T30
Torx T25
Spark plug socket
10mm extended socket
2 3/8 drive extensions
Tape (trust me on this)
Wrench
Torque Wrench

Parts Needed:
8 new NGK spark plugs ($28 each at dealer, or under $2 each at Advance Auto)

Procedure:
Using the T30 torx screwdriver remove the four screws that hold the plastic engine cover to the top of the engine.

I also removed the plastic guards above the radiator fan for better access (T25)

I took this opportunity to vacuum the top of the engine and then used some compressed air to clean the dust and dirt off the engine. (do not do this with the spark plugs out!!!)

The next part that comes off is the "BMW" side covers. They will just pull straight out. They are held in by friction. No tools are needed for removal.

Now you will be looking at the coils on the spark plugs.

The coils should be removed one at a time. I started at the front and worked my way back to the firewall.
Below is a coil that has been removed.

Some of these are difficult to remove and will require some serious pulling. Rotate them back and forth to loosen the coils. Do not use any tools to pry the coils out. You do not want to break the harness clip.

The rear plugs (closest to the firewall) are a serious PITA. I needed to tape a few shorter 3/8 extensions together as I put them into the spark plug hole. Removing them I needed to cut the tape and remove each piece one at a time.

Below is the "tool" I made

Be sure to apply anti-seize on the threads before installing the new sparkplugs.
Torque the new sparkplugs in to 19 ft-lbs (or whatever the plugs state)

Push on the coil and be sure it "pops" back on. It will kind of click when it is on all the way. Clip on the harness and you are back in business.

Be sure to start the car before putting the covers back on the engine and take this time to reset the spark plug counter to 100k.
• Put the key in, do not put your foot on the brake
• Hit the start button
• Hold down the trip reset for 10 sec.
• Page through until you get to spark plugs and reset the value

My wife noticed MPG went from 24mpg to 25.6 mpg. Looks like the spark plugs were due! I changed them at 95k.
 
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