[P416]

Hey I have a BMW E90 2011 323i. Yesterday my car started misfiring and stumbling while stopped. Engine light turned on I got the code P0303 Cylinder 3 misfire. I ordered spark plugs online from germanparts.ca

This is what i purchased: BOSCH FR7NPP332 (OEM#12122158253)
https://order.germanparts.ca/parts/b...2.5l-24v/2329B

According to realoem.com my car came with (OEM#12120035915)

Now I'm thinking if I ordered the wrong plugs and if I shouldve bought NGK PLZFR6A11S (OEM#12120035915) instead:
https://order.germanparts.ca/parts/b...2.5l-24v/1329B

Will the ones I purchased fit my car even tho it has a different OEM#?

Please advise,
Thank you.

[Bmwner]

Same car and same situation... BOSCH FR7NPP332 Spark Plugs for almost 2 years with no problems at all.

[P416]

Originally Posted by Bmwner

Same car and same situation... BOSCH FR7NPP332 Spark Plugs for almost 2 years with no problems at all.

Thanks! I almost emailed germanparts if it's possible to cancel my order if it hasnt shipped yet. I will give that product a try.

[The Geezer]

Code P0303 Cylinder 3 misfire, might be injectors more then plugs.

I had codes just a few weeks ago
P0301
P0300
P0304

Injectors were all replaced, no more issues.

Just a heads up that it might not be or could be more then plugs alone.

[P416]

Originally Posted by The Geezer

Code P0303 Cylinder 3 misfire, might be injectors more then plugs.

I had codes just a few weeks ago
P0301
P0300
P0304

Injectors were all replaced, no more issues.

Just a heads up that it might not be or could be more then plugs alone.

If its the injector do i have to replace all of it or just the one that failed?

[The Geezer]

I replaced all of mind due to older index, if you got Index 5 index 8 or index 9 you should replace them all with index 11 or 12.

Old rule of thumb, once one goes the others will follow at some point. Just my 2 cents worth.

But yes you can just change the one injector if thats your only option.

I am not sure about yours, but mine new OEM from BMW were about $350 each, I ended up getting new/used ones for $75 each

[P416]

Originally Posted by Bmwner

Same car and same situation... BOSCH FR7NPP332 Spark Plugs for almost 2 years with no problems at all.

Hey man shop just emailed me and said that the spark plugs are not compatible with a 2011 323i

"that part number doesn’t match with your car. My software is giving me a part number of 12120037663 for plugs"

Can you confirm if you have the Bosch #12122158253

Thanks

[Bmwner]

i found one of the boxes...

[P416]

Originally Posted by Bmwner

i found one of the boxes...

Not sure why the shop said it's not compatible.
Does it need to have the same OEM#?

My car came with OEM#12120035915

I ordered Bosch OEM#12122158253

[Bmwner]

Originally Posted by P416

Not sure why the shop said it's not compatible.
Does it need to have the same OEM#?

My car came with OEM#12120035915

I ordered Bosch OEM#12122158253

I bought these Bosh because i saw them on Germnparts.ca and so fr so good. Did Germanparts confirm fitment ? . If you're not sure , I would say return them and order the NGK plugs .

[P416]

Originally Posted by Bmwner

I bought these Bosh because i saw them on Germnparts.ca and so fr so good. Did Germanparts confirm fitment ? . If you're not sure , I would say return them and order the NGK plugs .

BMW dealer emailed me

"The spark plug you list is for the same car but different production date. I need your vin to give you the correct info."

"(OEM#12120035915) substitutes to (OEM#12122158253) so technically they are the same part"

He said that I have the wrong plugs unless the NGK crosses to the Bosch.

and I'm still confused. I'm looking at realoem.com both #12120037663 NGK & #12122158253 was both found on a E90 LCI 2007-2011

and it says Supersedes:
12120032138 NGK (09/01/2004 - 12/15/2009) What does that mean?

[Bmwner]

Originally Posted by P416

BMW dealer emailed me

"The spark plug you list is for the same car but different production date. I need your vin to give you the correct info."

"(OEM#12120035915) substitutes to (OEM#12122158253) so technically they are the same part"

He said that I have the wrong plugs unless the NGK crosses to the Bosch.

and I'm still confused. I'm looking at realoem.com both #12120037663 NGK & #12122158253 was both found on a E90 LCI 2007-2011

and it says Supersedes:
12120032138 NGK (09/01/2004 - 12/15/2009) What does that mean?

to be honest, im confused and dont know what to tell u. The bosch spark plugs work. I mean, no misfires, no warning lights , no problems at all. I did not even notice any difference between those and the OEM S/P.

[Bmw_Crazy]

Originally Posted by P416

Hey I have a BMW E90 2011 323i. Yesterday my car started misfiring and stumbling while stopped. Engine light turned on I got the code P0303 Cylinder 3 misfire. I ordered spark plugs online from germanparts.ca

This is what i purchased: BOSCH FR7NPP332 (OEM#12122158253)
https://order.germanparts.ca/parts/b...2.5l-24v/2329B



According to realoem.com my car came with (OEM#12120035915)

Now I'm thinking if I ordered the wrong plugs and if I shouldve bought NGK PLZFR6A11S (OEM#12120035915) instead:
https://order.germanparts.ca/parts/b...2.5l-24v/1329B

Will the ones I purchased fit my car even tho it has a different OEM#?

Please advise,
Thank you.

Check your coils same thing happend to me..

[The Geezer]

When did the check engine light come on to let you know you had a issue?

If it was under under load (while driving) would be a coil issue most likely.

If it was from cold start would be a fuel injector issue most likely.

[Patty77]

Originally Posted by The Geezer

I replaced all of mind due to older index, if you got Index 5 index 8 or index 9 you should replace them all with index 11 or 12.

Old rule of thumb, once one goes the others will follow at some point. Just my 2 cents worth.

But yes you can just change the one injector if thats your only option.

I am not sure about yours, but mine new OEM from BMW were about $350 each, I ended up getting new/used ones for $75 each

Hi, I'm counting myself lucky to stumble upon your post because I'm running into the exact same situation as you have.

I also drive a E90 335xi ('09 sedan) and my injectors are due to be replaced because they are leaking and they are low index #s. I'm applying that rule of thumb and I'm preparing to have all 6 upgraded to index 11 or 12, any chance you could please refer me to your supplier?

[The Geezer]

i got mine from a friend that works for BMW.

[bimmergixxer]

These engines are famous for coil failure. I would doubt the plug would fail but its probably the coil. Best way to check is to unplug the coil and see if there is any change in engine rpm. Also take off the coil of cylinder 3 and switch it to another cylinder like #1 since its easiest, and you will probably now have a cylinder 1 misfire.

[MohiAli]

Hi, Please help! read all the pointers and followed them.

I had engine management light come up whilst driving one day.

Had it diagnosed. Misfire Cylinder 2&3 P302 and P303.
To eliminate the error, changed the coils around to test swapped 1 with 2 and 3 with 4 but fault remained in the same cylinders 2&3.
Changed the spark plugs around, again fault remained on cylinder 2 & 3.
Got the garage to then swap injectors around, fault only came up only on Cylinder 3 so to be safe had all 4 injectors changed upgraded to Index 9 from Index 7. Fault has now returned to Cylinder 2 and 3! After so much time, money and effort back to square one.
Car now in limp mode and management light come up as fast as you clear it.

I did notice however, when engine on and i disconnect the 2nd and 3rd coil (1 at a time) the engine carries on running but if i do the same with 1 and 4 engine almost cuts out. Not sure if that means anything to anyone.

Should I change all spark plugs and coils also or would that be a waste of time and funds?

Please can someone assist a fellow Bimmer driver in distress??

[misterjay3]

Having similar issue and swapped in new coils and plugs but have low compression

[plilp]

I have an -08 E91 with the n53 3liter motor and I'm having similar misfire issues in cylinder 3. Spark plugs (NGK) and ignition coils (Bosch) have been changed but it's still happening. After changing the coils the misfire didn't happen for 2 days but then reappeared. I have ordered new injectors (index 11) but I'm afraid it won't solve the issue... my symptoms in detail:

After starting the car there's no issues. I can drive for a good 15-20min before the symptoms appear. The check engine light will go on and the engine starts running roughly, rpm will start to fluctuate as well. When accelerating there's no power and the car noticeably shakes when slowly picking up speed. Idle is then also rough and rpm keeps fluctuating. Issue will not solve while the engine is hot, even if the car is turned off and back on the symptoms start immediately. Then the next day or after properly cooling down, the symptoms are gone again. As mentioned the only consistent error code I've received from the engine is P0303.

I believe the injectors are still the original ones or at least very old. I haven't checked myself. I used a petrol system cleaner, the kind you pour in the gas tank, and I feel like it improved the situation slightly, so I'm hopeful that replacing the injectors will fix the issue but still afraid it doesn't.

[tomasp001]

Originally Posted by MohiAli

Hi, Please help! read all the pointers and followed them.

I had engine management light come up whilst driving one day.

Had it diagnosed. Misfire Cylinder 2&3 P302 and P303.
To eliminate the error, changed the coils around to test swapped 1 with 2 and 3 with 4 but fault remained in the same cylinders 2&3.
Changed the spark plugs around, again fault remained on cylinder 2 & 3.
Got the garage to then swap injectors around, fault only came up only on Cylinder 3 so to be safe had all 4 injectors changed upgraded to Index 9 from Index 7. Fault has now returned to Cylinder 2 and 3! After so much time, money and effort back to square one.
Car now in limp mode and management light come up as fast as you clear it.

I did notice however, when engine on and i disconnect the 2nd and 3rd coil (1 at a time) the engine carries on running but if i do the same with 1 and 4 engine almost cuts out. Not sure if that means anything to anyone.

Should I change all spark plugs and coils also or would that be a waste of time and funds?

Please can someone assist a fellow Bimmer driver in distress??

Your process of elimination was correct! You switched the coils and plugs around but to no avail but when you switched the injectors you had some success. So it is most likely a faulty injector here based on what you posted. But it sounds like you bought "used" index 9 injectors here, So I have a few questions:

1. When you bought the used injectors, did you replace the expanding o-ring and the decoupling element? That could cause an issue where the injector is not seated correctly.

2. IF you did successfully replace those elements of the injector the last things are, was it installed in a timely manner? (After the self expanding o-ring is exposed [taking off the cap that comes with the injector], it starts to expand. So was the injectors replaced pretty quickly?

3. Last thing, if it was installed correctly, WAS IT CODED??? After installation the injectors has to be coded to new values. After coding, delete all errors and try starting the car.

4. If you did everything here and still got errors, this is the extent of my knowledge with this subject, sorry, LOL.

Originally Posted by plilp

I have an -08 E91 with the n53 3liter motor and I'm having similar misfire issues in cylinder 3. Spark plugs (NGK) and ignition coils (Bosch) have been changed but it's still happening. After changing the coils the misfire didn't happen for 2 days but then reappeared. I have ordered new injectors (index 11) but I'm afraid it won't solve the issue... my symptoms in detail:

After starting the car there's no issues. I can drive for a good 15-20min before the symptoms appear. The check engine light will go on and the engine starts running roughly, rpm will start to fluctuate as well. When accelerating there's no power and the car noticeably shakes when slowly picking up speed. Idle is then also rough and rpm keeps fluctuating. Issue will not solve while the engine is hot, even if the car is turned off and back on the symptoms start immediately. Then the next day or after properly cooling down, the symptoms are gone again. As mentioned the only consistent error code I've received from the engine is P0303.

I believe the injectors are still the original ones or at least very old. I haven't checked myself. I used a petrol system cleaner, the kind you pour in the gas tank, and I feel like it improved the situation slightly, so I'm hopeful that replacing the injectors will fix the issue but still afraid it doesn't.

Please refer to my response to the other quote on this message, I believe you are going through what he's going through. So when you install the new injectors please go through the checklist above to avoid any issues. If you replaced the plugs and coils with OEM spec parts and you are stock, you shouldnt worry about "gapping plugs". Hopefully this helps, Good luck friends.

Video Reference to how to properly change injectors (cred: Jake Spence):

[3RC4N]

Originally Posted by plilp

I have an -08 E91 with the n53 3liter motor and I'm having similar misfire issues in cylinder 3. Spark plugs (NGK) and ignition coils (Bosch) have been changed but it's still happening. After changing the coils the misfire didn't happen for 2 days but then reappeared. I have ordered new injectors (index 11) but I'm afraid it won't solve the issue... my symptoms in detail:

After starting the car there's no issues. I can drive for a good 15-20min before the symptoms appear. The check engine light will go on and the engine starts running roughly, rpm will start to fluctuate as well. When accelerating there's no power and the car noticeably shakes when slowly picking up speed. Idle is then also rough and rpm keeps fluctuating. Issue will not solve while the engine is hot, even if the car is turned off and back on the symptoms start immediately. Then the next day or after properly cooling down, the symptoms are gone again. As mentioned the only consistent error code I've received from the engine is P0303.

I believe the injectors are still the original ones or at least very old. I haven't checked myself. I used a petrol system cleaner, the kind you pour in the gas tank, and I feel like it improved the situation slightly, so I'm hopeful that replacing the injectors will fix the issue but still afraid it doesn't.

I have exactly the same problem:

If engine is cold, it runs almost perfect.
But after 20 Minutes and the engine is heated up... Misfires cylinder 3.


I have renewed Coils and Plug -> nothing changed, problem still exists

Changed Injector 3 with a spare one from friend -> nothing changed, problem still exists

I have sent Injector 3 to a professional refub shob -> no faulds at injector could found, it has been cleaned and seals has been renewed -> nothing changed, problem still exists.

So my question, could you solve your Problem in the last 2 Years? And what was the reason for that problem?