SES Light - Shaking during Accel

[cbl117]

I was merging onto the freeway tonight at 50% throttle and felt some hesitations and the SES light came on. While the light was on the car would shake a bit when accelerating and the engine would stutter slightly. The car sounded similar to a older WRX with an exhaust if that means anything to anyone. After about 10 mins the light went away and the car drove fine again. I drove for about 20-30 more min home (not pushing the car) and everything seemed ok.

I haven't had a chance to take it to AutoZone to read any codes, but wanted to see if anyone had any ideas.

[cbl117]

found a thread over in E90 that sounds similar to my situation.

http://www.e90post.com/forums/showthread.php?t=581254

I'm guessing I had a misfire, threw off ignition management, misfires didn't continue and the engine recovered and the light went out. Now the tricky part...what caused the misfire. Usual suspects: injectors, coils, plugs?

[Grinchxvx]

It's a misfire, these are the exact symptoms my car had when my cylinder 6 coil went out. It's funny how much it really sounds like a Subaru haha

[SchismX]

When was the last time you changed your plugs? I would start there.

[cbl117]

Plugs were changed about 10k miles ago.

[135Pats]

It likely missed. Not a big deal.

How old are the coils on the car? A "typical" misfire is spark-related, so start with coils and plugs. They're cheap to replace, easy to inspect or swap around (to determine if it's a single cylinder causing the issue), and readily available.

Pump gas?

[ShocknAwe]

Honestly, I'd only worry about it if it misses again.

Every once in a blue moon I'll get a random unrepeated miss. NBD.

[cbl117]

Originally Posted by 135Pats

It likely missed. Not a big deal.

How old are the coils on the car? A "typical" misfire is spark-related, so start with coils and plugs. They're cheap to replace, easy to inspect or swap around (to determine if it's a single cylinder causing the issue), and readily available.

Pump gas?

Pump gas with a mix of 91 and 100 to achieve 93 oct. I run this once in a while.

Coils are original to my knowledge and car has 50k miles. I changed the plugs less than a year ago. Plugs have about 10k miles on them now.

I drove to work this morning without issue. So in total I've gone about 50 miles since the misfire and no repeat. But I haven't done any WOT yet.

[135Pats]

Originally Posted by cbl117

Pump gas with a mix of 91 and 100 to achieve 93 oct. I run this once in a while.

Coils are original to my knowledge and car has 50k miles. I changed the plugs less than a year ago. Plugs have about 10k miles on them now.

I drove to work this morning without issue. So in total I've gone about 50 miles since the misfire and no repeat. But I haven't done any WOT yet.

Coin flip as to whether it would miss under heavy load....If the coils are factory, it's likely those are the culprit. Personally, at 50K i'd just replace all six of them. It'll take you 15 minutes if you've never done it before, couldn't be easier.

[cbl117]

Originally Posted by 135Pats

Coin flip as to whether it would miss under heavy load....If the coils are factory, it's likely those are the culprit. Personally, at 50K i'd just replace all six of them. It'll take you 15 minutes if you've never done it before, couldn't be easier.

Just checked coil cost online and less than $300 for a set of six. Not bad. Is it ok to purchase at getbmwparts.com? I'm on CPO. You think its worth the hassle of getting the culprit replaced under warranty? I'm for sure in it for the $50 deductible and its likely they will replace only the faulty ones. What is likelihood that an injector is going bad? I had my dealer do the injector cleaning service around 40k. They said it would help prolong their life.

[135Pats]

Originally Posted by cbl117

Just checked coil cost online and less than $300 for a set of six. Not bad. Is it ok to purchase at getbmwparts.com? I'm on CPO. You think its worth the hassle of getting the culprit replaced under warranty? I'm for sure in it for the $50 deductible and its likely they will replace only the faulty ones. What is likelihood that an injector is going bad? I had my dealer do the injector cleaning service around 40k. They said it would help prolong their life.

Without codes and logs we're just guessing. It's far more likely you had a spark-related miss, but injectors go as do all other parts attached to the motor.

Without codes, it's 100% speculative. That "bucking" feeling happens as a result of several dozen root issues, so it doesn't get us very far in terms of diagnosing.

[Dackelone]

Originally Posted by cbl117

Just checked coil cost online and less than $300 for a set of six. Not bad. Is it ok to purchase at getbmwparts.com? I'm on CPO. You think its worth the hassle of getting the culprit replaced under warranty? I'm for sure in it for the $50 deductible and its likely they will replace only the faulty ones. What is likelihood that an injector is going bad? I had my dealer do the injector cleaning service around 40k. They said it would help prolong their life.

Its probably worth that $50 deductable to get over $1K in parts replaced. Hopefully your SES code is still in there.


Q: Did you use BMW dealer bought plugs? Non-dealer plugs have been known to cause issues. Usually the order you replace things is cheap to $$$. So that's: plugs, coils, injectors.

Running some "dealer" fuel injector does nothing to make the injectors last longer. Only helps dollars flow from your wallet to the dealer's. IF your running an early injector... I would push hard for your dealer to replace all SIX injectors. They are suppose to replace the injectors in sets(banks) of three.

Did your car ever have the HPFP replaced? That might also be a culprit. But that usually surfaces bc of long cranks on cold starts.


Dackel


Btw.. there were also some recalls that you might check to see if they were ever done to your CPO. Of course the dealer should have checked on that before selling you the car. Battery cable recall and insulation on the b-pillar(can catch on fire in a crash) are the ones that come to mind.

[cbl117]

I have an update for anyone subbed to this thread and/or interested in causes for intermittent SES lights under heavy load.

I got my 4th intermittent SES light this past Wednesday night while accelerating in 3rd gear to merge on the freeway. Slight incline and 75% throttle. Decided then it was time to take it in and see whats up.

Dealer found a bunch of codes and in particular found a code for fouled intake manifold. The good news is the dealer will clean the intake manifold (walnut blast) under CPO. The bad news is BMW requires the service be performed with a fresh set of plugs and oil. Not sure how much I buy that but I could use new plugs and new oil so what the hell. The cost of plugs and oil is worth getting the walnut blast to me so I'm happy.

I get the car back Tuesday and was told by the SA that the performance difference will be "freakin awesome". Can't wait!

[cbl117]

Originally Posted by Dackelone

Its probably worth that $50 deductable to get over $1K in parts replaced. Hopefully your SES code is still in there.


Q: Did you use BMW dealer bought plugs? Non-dealer plugs have been known to cause issues. Usually the order you replace things is cheap to $$$. So that's: plugs, coils, injectors.

Running some "dealer" fuel injector does nothing to make the injectors last longer. Only helps dollars flow from your wallet to the dealer's. IF your running an early injector... I would push hard for your dealer to replace all SIX injectors. They are suppose to replace the injectors in sets(banks) of three.

Did your car ever have the HPFP replaced? That might also be a culprit. But that usually surfaces bc of long cranks on cold starts.


Dackel


Btw.. there were also some recalls that you might check to see if they were ever done to your CPO. Of course the dealer should have checked on that before selling you the car. Battery cable recall and insulation on the b-pillar(can catch on fire in a crash) are the ones that come to mind.

Dack, I didn't see your post until now. HPFP has been replaced and I'm up to date on my recalls. Appreciate the heads up though.

For the forum: If I'm getting walnut blast, new plugs, new oil, is it worth changing out the coils even if I'm not getting any codes from them? Will I gain/notice any performance increase with fresh coils vs coils with 50k miles on them?

[Dackelone]

Originally Posted by cbl117

Dack, I didn't see your post until now. HPFP has been replaced and I'm up to date on my recalls. Appreciate the heads up though.

For the forum: If I'm getting walnut blast, new plugs, new oil, is it worth changing out the coils even if I'm not getting any codes from them? Will I gain/notice any performance increase with fresh coils vs coils with 50k miles on them?

coils are usually needed at ~80K miles. (or if one or two break when R&Ring during a spark plug change) I would just do the walnut blasting and see how your engine runs. Then you can always replace the coils with new ones or upgraded coil packs - later on.

Dackel

[cbl117]

Originally Posted by Dackelone

coils are usually needed at ~80K miles. (or if one or two break when R&Ring during a spark plug change) I would just do the walnut blasting and see how your engine runs. Then you can always replace the coils with new ones or upgraded coil packs - later on.

Dackel

Sounds like a good plan Dack. Is there any other maintenance to be done to the N54 to make it perform better? Assuming injectors and coils don't need changing.

BTW..400th Post!

[Dackelone]

Originally Posted by cbl117

Sounds like a good plan Dack. Is there any other maintenance to be done to the N54 to make it perform better? Assuming injectors and coils don't need changing.

BTW..400th Post!

There have been MANY injector versions by bmw. IF your still on the original ones... sooner or later you will need to replace them all. other than spark plugs and coils... maybe HPFP the N54/N55 engines are really good.

Some guys having issues with rattling wategates/turbos. Most just replace the turbo(s) but replacing just the WG's can also be done.

Carbon buildup seems to be our main problem. IF your car has close to ~80K miles you should also thinking about replaing the water pump(electric) and thermostat.

Dackel

[cbl117]

Originally Posted by Dackelone

There have been MANY injector versions by bmw. IF your still on the original ones... sooner or later you will need to replace them all. other than spark plugs and coils... maybe HPFP the N54/N55 engines are really good.

Some guys having issues with rattling wategates/turbos. Most just replace the turbo(s) but replacing just the WG's can also be done.

Carbon buildup seems to be our main problem. IF your car has close to ~80K miles you should also thinking about replaing the water pump(electric) and thermostat.

Dackel

Is that 80k in km or mi? I currently have 52k miles. I was considering changing the water pump and thermostat at 60k miles as preventative maintenance. Dealer took apart turbos and said they were in good shape, so hopefully they last a while

[Dackelone]

Originally Posted by cbl117

Is that 80k in km or mi? I currently have 52k miles. I was considering changing the water pump and thermostat at 60k miles as preventative maintenance. Dealer took apart turbos and said they were in good shape, so hopefully they last a while

80K miles. But there is really no telling when these electric water pumps will fail. Some fail early and some last over 100k miles. Most seems to crap out between 60K to 80k miles.

I don't understand what you meant by yiur dealer took apart your turbos? WHY would they even do THAT? Sounds like BS on their part. ???

Dackel

[cbl117]

Originally Posted by Dackelone

80K miles. But there is really no telling when these electric water pumps will fail. Some fail early and some last over 100k miles. Most seems to crap out between 60K to 80k miles.

I don't understand what you meant by yiur dealer took apart your turbos? WHY would they even do THAT? Sounds like BS on their part. ???

Dackel

Not sure what the SA meant. Could be BS to make me feel better. I think they just checked that the waste gates were opening and closing properly??

[cbl117]

Originally Posted by Dackelone

There have been MANY injector versions by bmw. IF your still on the original ones... sooner or later you will need to replace them all. other than spark plugs and coils... maybe HPFP the N54/N55 engines are really good.

Some guys having issues with rattling wategates/turbos. Most just replace the turbo(s) but replacing just the WG's can also be done.

Carbon buildup seems to be our main problem. IF your car has close to ~80K miles you should also thinking about replaing the water pump(electric) and thermostat.

Dackel

Dack,

Good news and bad news. Good news is when I went to pick up the car today I found out they replaced ALL 6 injectors under CPO warranty! Apparently 2 plugs were fouled so sounds like 2 were starting to leak?

The bad news is I noticed the car would shimmy and there was vibration in the steering wheel as soon as I left the dealer. I immediately took the car back to the dealer and took the SA out to show what was going on. The dash lit up with DSC, DBC, and start assist (MT) malfunctions. Also the brake light was on and when they read the key it was showing brakes due in -400,000 miles lol. The SA said it sounds like a reprogramming issue since they had to totally reset the car. I had them write up the ticket to confirm the Dinan software is still loaded on the car. I hope its nothing major!

[cbl117]

Got the car back today. The reason the codes popped up is because the dealer forgot to calibrate the steering wheel sensor when they reset the car. Also found out they erased the dinan stage 2 yesterday and luckily I noticed and asked them to verify. I felt the difference immediately when I picked the car up today.

Theres only about 30 miles since the reset and fresh reinstall of the software, but the car started to feel faster than before. Waay smoother idle, very quick throttle response now especially below 3k rpms. I bought the car used with 21k miles and I can honestly say its never felt this smooth and responsive.

Summary of work:
Walnut blasting
All new injectors
All new spark plugs
Oil change

Best part is it was only $875 out the door!