[rick100]

Hey guys , Im having a small issue with my 2011 328xi. I actually had this same problem last year and it ended up being the plugs.

Basically I m experiencing small hiccups/ hesitation between 75 - 85 mph. It does not happen if I accelerate straight to 85 ( either hard or soft) . I m able to duplicate the problem every time if I m driving at around 75 mph , let go off the gas pedal and then press the gas pedal to climb to 85 mph. The car will get to 85 but I can feel small hiccups along the time , nothing big , but its definitely there

There is not codes or engine light. The car drives fine , power is fine , transmission shifts smooth. All the plugs were replaced last year, which fix the problem ( which was identical, although the hiccups were a bit more aggressive), so my guess is coils , which have not been replaced yet. Question is , should I replace the plugs again if I install new coils?? , the plugs have around 25 000 miles on them , maybe a bit more...

Also , how hard is to replace coils , I actually bought a third car and I m planning on parking the bmw for the winter, so I may feel a bit adventurous on this one...

Any other guess , on what could be wrong?? ... dirty air filter?? havent changed that in a year...

[gamesfrager]

I had a very similar issue. I replaced plugs and coils.
Replacing the plugs and/or coils is very straight forward.
So many youtube videos showing how it's done.
For this, you don't even need a torque wrench, only if you are replacing plugs as well.

[nsjames]

plugs and coils is incredibly easy on these cars.

remove cowling
remove plastic cover
pop out coils
remove plugs.

installation is the reverse of removal.

part throttle acceleration issues are generally a PITA to track down. Have you got some way of logging the data from te car?

[rick100]

Yea i actually saw the videos. Looks pretty damn easy. Do u guys think i should change the plugs too?... they were replaced last year. Maybe 15-20 k miles on them...


I saw a set of bosh on amazon for 200 canadian dollars. Not sure if bosh is the best way to go.

[nsjames]

delphi is the new preferred coil brand.

be careful of counterfeits on amazon, it's a big problem.

They're $29 a piece at FCP and you'll get a lifetime warranty
https://www.fcpeuro.com/products/bmw...QaAtwnEALw_wcB

if you're going to the trouble of swapping coils I would do the plugs. You're going to do more work gettnig there than doing the plugs.
worn plugs are what kills coils. Keep the plugs fresh and coils don't go bad.

[JuniorB]

When was the last time you changed your fuel filter? Dosent sound like a misfire, check fuel pressure,,filter.,

[rick100]

change fuel filter? aren't they inside the fuel tank?

[nsjames]

Originally Posted by rick100

change fuel filter? aren't they inside the fuel tank?

it is. it's a strainer sock in the bottom of the bucket.

not replaceable.

if you really want, go to auto zone, rent the fuel testing kit, it will screw into the schrader valve on the rail.

but I really doubt it's a fuel pressure issue, especially at partial throttle. That's something that would become more apparent at WOT when fuel demands are highest and you're draining the rail fast.

[rick100]

i think its coils because I had the exact same issue before and it turned out to be the plugs. so Delphi coils are better than bosh ? ...

[rick100]

so I did some research on the delphi coils and everyone says they do not sit well...

[nsjames]

they worked fine in my junk.

36K miles on my set.
do what you're comfortable with.

[gamesfrager]

Since you are in Canada, I would order it from rockauto. That's where I got them from.
They were the cheapest that I could find.

I went yesterday for some shopping, and while reversing, the car was shaking hard, and it only happened on reverse.
I quickly scanned with Bimergeeks Protool and the fault was cyl #4 misfire.
Swapped it with cyl #1 coil and fault code fallowed.

This evening I replaced it with one of the older coils and no fault.
So now I'm filing a warranty return.
Maybe worth it to buy an extra coil? my order was Bosch coils.

[rick100]

Ok guys , so my brother and I are going to make this a DIY. I just want to make sure these coils and plugs are going to work , so please I need some help. I have double check some sites and it seems correct. Rockauto it is , as they are the cheapest for me

Plugs
NGK 95712 Laser Platinum Info
Gap 0.044"; Actual OE Part

Coil

BOSCH 0221504470 {#00044} Info
FitsEngine Code N51B30A; Actual OE part; One per cylinder
OrEngine Code N52; Actual OE part; One per cylinder

I have a question ecs has a different part number for the coils , however if I cross check both , if seems like they are the same. What a headache

https://www.ecstuning.com/b-bosch-pa...137594937~bos/

The job looks easier than finding the right part number.

Im wondering if the laser iridium ngk are going to work with the bosh coils and if they are good.

Any help pls let me know . I want to pull the trigger and get to work

[gamesfrager]

These were the parts that I ordered:

BOSCH 0221504470 Ignition Coil (8511.30.0020) $ 25.33 CAD
DENSO 3421 Spark Plug (8511.10.0000) $ 7.13 CAD
This was for my 2011 328i sedan.

Tools I used:

- 3/8 socket set
- screw driver (optional, but it helped to use it with the 3/8 socket set)
- Allen key type bits, I actually used long alen keys you need it to remove the engine cover
- 3/8 torque wrench (needed if you are replacing spark plugs)
- 3/8 extension (needed if you are replacing spark plugs)
- 3/8 16mm thin wall socket (needed if you are replacing spark plugs) I got mine from Princess Auto because I ordered 14mm from Amazon and they did not fit, so I had to rush and grab one from Princess Auto
- A pair of gloves, not just those nitrile gloves, but thicker ones to spare your self the cuts
- A trim removal tool (optional, I used it to unclip the hose rail over the engine cover)

For my car, I had to remove the left strut bar bolt just so I can swing it out of my way, I needed this so I can access the #5 and #6 spark plugs
Not sure if you can get away without doing this step by using some angled socket adapter like this
http://i.ebayimg.com/images/i/221905...-1/s-l1000.jpg

Good luck and let us know how it turns out.

[rick100]

So i bought the coils and plugs

Trying to figured out the spark plug socket for a 2011 328. It seems like it is a 5/8 socket . ( although some people call for a 3/8) , anyways , I tried ECS tuning , 15 bucks for the socket and 40 bucks to ship to canada lol.

I found these 4 , 3 are an amazon sockets, which everyone seems to like. The other one is a princess auto local vendor

Please let me know what you think?

https://www.amazon.ca/GearWrench-805...rk+plug+socket


https://www.amazon.ca/OEMTOOLS-22885...rk+plug+socket

https://www.amazon.com/Spark-Plug-So...ustomerReviews

https://www.princessauto.com/en/deta...et/A-p8668345e

[gamesfrager]

The spark plug socket is a thin wall 16mm.
I made the mistake of buying the 14mm socket from Amazon and it didn't fit.
I got it from Princess Auto for $5.

Check Canadiantire or Princess Auto if there is one nearby.

[rick100]

Originally Posted by gamesfrager

The spark plug socket is a thin wall 16mm.
I made the mistake of buying the 14mm socket from Amazon and it didn't fit.
I got it from Princess Auto for $5.

Check Canadiantire or Princess Auto if there is one nearby.

so the last link for princess auto should work right? ... It says 16mm but i m not sure if it is a thin wall

[gamesfrager]

That link is for 14mm, it says that on the image.
And if you are going there to pick it up; take one of the new spark plugs with you to confirm.
That's what I did
And yes, that's a thin wall one.

[gamesfrager]

Humm... the image says 14mm, description says 16mm.
Looks like it is 5/8" ~ 16mm
Yea, I guess it is.

[rick100]

Originally Posted by gamesfrager

Humm... the image says 14mm, description says 16mm.
Looks like it is 5/8" ~ 16mm
Yea, I guess it is.

yea I was thinking of just taking one with me . Thanks !!

[gamesfrager]

And make sure you have the 3/8 extension for the torque wrench/ratchet.

Good luck, and post back your experience.

[rick100]

so I finally changed the plugs and coils. My brother and dad came to my house to visit. The process was actually pretty easy overall , I had to adjust the gap a little bit but nothing crazy .

I had a misfire on cylinder 1 and 4 on first start up , I believe the connector for the coil was not fully seated , so I had to removed and reinstalled . Car idles smooth , no engine light , I took it for a 30 minute drive on the highway and I m not having the hiccup anymore.

One thing that surprised me was the plugs that came out , the gap was at 0.0052 ( I may be adding another zero there, but you know what I mean). They looked pretty damn burn for plugs that were changed last year and have 20 000 miles on them .

I do not track the car, but I don ran it hard from time to time , I also have headers, 3 stage intake , tune , k and n filter , charcoal delete, highflow cats so I m not sure if all that contributes to the premature wear ??... The mechanic I take the car to is pretty trustworthy so I do not think he charged me to changed it and never did . Maybe thats the way plugs get after one year or so of use , maybe it is not too bad

Anyways , car is running smooth right now. Old plugs