[carl_lazlo]

In the past few weeks I have noticed a strange issue with my 335xi sedan at high speeds. I am cruzing on the highway at or above 65mph and I am in 6th gear and giving the car about 1/2 throttle. (Just enough to keep my speed and stay in 6th). If I back off on the throttle and then give it gas again I will feel the car hesitate a small amount and shutter 3 or 4 times very slightly as my speed increases. (This is VERY subtle but after driving 40K miles in this 335 and another 60K on my last 335 I no what feels unusual.) This ONLY happens on the highway under these conditions and only happens about 50% of the time. I am taking the car in tomorrow to be looked at by the dealer but I wanted some opinions before I went in.


Could this be a HPFP issue? Intake maybe?

Carl

[RonRed89]

Originally Posted by carl_lazlo

In the past few weeks I have noticed a strange issue with my 335xi sedan at high speeds. I am cruzing on the highway at or above 65mph and I am in 6th gear and giving the car about 1/2 throttle. (Just enough to keep my speed and stay in 6th). If I back off on the throttle and then give it gas again I will feel the car hesitate a small amount and shutter 3 or 4 times very slightly as my speed increases. (This is VERY subtle but after driving 40K miles in this 335 and another 60K on my last 335 I no what feels unusual.) This ONLY happens on the highway under these conditions and only happens about 50% of the time. I am taking the car in tomorrow to be looked at by the dealer but I wanted some opinions before I went in.


Could this be a HPFP issue? Intake maybe?

Carl

I had the exact same issue. Between 2-3K RPM in 3-6 gear, I would feel these light pulses of hesitation. This only happened between 2-3K RPM because after 3K, it pulled hard.

I just got the car back from the dealer yesterday, and they just flashed the ECU with a newer version of software. So far, after 1 day, I have not had the issue nor the long cranks on cold start which was my other issue. I can report more after a couple of days with the car, but initially it seems to have fixed the issue.

Ron

[ibimmer954]

Maybe some weirdness with the traction control? Is your DTC light coming on?

[carl_lazlo]

I have heard the latest software causes more turbo lag.does anyone know if the new version causes any problems?

[JJB]

Mine shakes if I'm crusing at that speed then floor it to pass.

I'm taking the car in next week, so I'll let you know what they say. Service Advisor thinks perhaps HPFP, but we'll see.

[Bcube]

Originally Posted by carl_lazlo

In the past few weeks I have noticed a strange issue with my 335xi sedan at high speeds. I am cruzing on the highway at or above 65mph and I am in 6th gear and giving the car about 1/2 throttle. (Just enough to keep my speed and stay in 6th). If I back off on the throttle and then give it gas again I will feel the car hesitate a small amount and shutter 3 or 4 times very slightly as my speed increases. (This is VERY subtle but after driving 40K miles in this 335 and another 60K on my last 335 I no what feels unusual.) This ONLY happens on the highway under these conditions and only happens about 50% of the time. I am taking the car in tomorrow to be looked at by the dealer but I wanted some opinions before I went in.


Could this be a HPFP issue? Intake maybe?

Carl

Same issue a while back: six injectors, six coils, and six spark plugs later before being fixed.

[carl_lazlo]

It looks like I was right about it being related to the hpfp. When they checked the ecu there were 5 or 6 shadow codes related to "low fuel rail pressure" or something like that. It was not enough to throw a code I could see but it did log in the ecu.

So has anyone noticed any performance issues after getting the new software?

[RonRed89]

Originally Posted by carl_lazlo

It looks like I was right about it being related to the hpfp. When they checked the ecu there were 5 or 6 shadow codes related to "low fuel rail pressure" or something like that. It was not enough to throw a code I could see but it did log in the ecu.

So has anyone noticed any performance issues after getting the new software?

I have yet to have a long crank condition, and the shuttering on acceleration has not recurred. At this point, it's too early to call it successful since it has only been a day for me, but early signs are looking good.

No performance benefits other than the lack of shuttering on load between 2k and 3k rpm.

There are additional menu options in the idrive and a revised warning when the navigation system fires up.

My car had 6 injectors, cal 1 coil and plug replaced before this update was done. Still on the original pump. 17k miles.

Ron

[ragingclue]

I have that same "pulsing" hesitation while cruising.

According to the dealer, it's nothing. Just like a whole bunch of the other non-issues I seem to have with this car.

[RonRed89]

Well. So much for the software update fixing everything. Still no long cranks, but the hesitation came back again today. Since someone on here mentioned traction control, I disabled it with the dtc button and the problem recurred right after.

Ron

[FirstBMWLA]

Been looking for something that describes what I'm experiencing. The things mentioned in this thread seem to describe what I'm feeling also. I feel the hesitation in 6th at highway speeds while maintaining speed. I also feel some hesitation in 2nd gear under WOT almost as if I letoff the throttle a bit and reapplied it repeatedly like a stuttering.

Wondering if this is related to my HPFP.

[carl_lazlo]

Originally Posted by FirstBMWLA

Been looking for something that describes what I'm experiencing. The things mentioned in this thread seem to describe what I'm feeling also. I feel the hesitation in 6th at highway speeds while maintaining speed. I also feel some hesitation in 2nd gear under WOT almost as if I letoff the throttle a bit and reapplied it repeatedly like a stuttering.

Wondering if this is related to my HPFP.

I've been so busy I totally forgot to provide an update on this. It looks like the dealer figured out my problem; it was not the HPFP, but the intake. I had 38K on the car when I took it in. The dealer spent 2 days with my car, ripping out the intake and cleaning all the carbon out. The pictures were insane! The carbon buildup was out of control.

The shop foreman said that the carbon buildup was keeping the valves from closing completely creating the strange hesitation and bucking I was feeling.

If your experiencing this same issue and have a good amount of miles on the car, have them clean the intake. The car is 99% better now.

CL

[FirstBMWLA]

I've been so busy I totally forgot to provide an update on this. It looks like the dealer figured out my problem; it was not the HPFP, but the intake. I had 38K on the car when I took it in. The dealer spent 2 days with my car, ripping out the intake and cleaning all the carbon out. The pictures were insane! The carbon buildup was out of control.

The shop foreman said that the carbon buildup was keeping the valves from closing completely creating the strange hesitation and bucking I was feeling.

If your experiencing this same issue and have a good amount of miles on the car, have them clean the intake. The car is 99% better now.

CL

I've got 25k miles on my car. Were you experiencing any check engine lights or limp modes or did you just complain to the dealer about what you were experiencing? Just not sure if I can get dealer to do anything without it throwing codes or something.

Thanks

[smc]

I've had this happen on several non-BMW cars and every time it was bad coils/plugs/wires.

[Christos]

Originally Posted by ragingclue

I have that same "pulsing" hesitation while cruising.

According to the dealer, it's nothing. Just like a whole bunch of the other non-issues I seem to have with this car.

I have a similar pulsing when cruising around 60/65 mph, but I just had my 4th HFPF replaced and new spark plugs, but still have the pulsing feeling???

[JJB]

Originally Posted by carl_lazlo

I've been so busy I totally forgot to provide an update on this. It looks like the dealer figured out my problem; it was not the HPFP, but the intake. I had 38K on the car when I took it in. The dealer spent 2 days with my car, ripping out the intake and cleaning all the carbon out. The pictures were insane! The carbon buildup was out of control.

The shop foreman said that the carbon buildup was keeping the valves from closing completely creating the strange hesitation and bucking I was feeling.

If your experiencing this same issue and have a good amount of miles on the car, have them clean the intake. The car is 99% better now.

CL

Same diagnosis here. Fixed my problems completely.

[FirstBMWLA]

Originally Posted by JJB

Same diagnosis here. Fixed my problems completely.

Those of you that had the issue resolved with the cleaning of the intake. Did you just complain about hesitation to the dealer or was the car actually throwing any codes. If it was just the hesitation did the dealer try to replicate the issue or did they just investigate it for you.

Just trying to figure out what I need to say to the SA exactly to get this resolved.

This thread has been helpful as it seems to be the issue I'm experiencing.

[JJB]

Originally Posted by FirstBMWLA

Those of you that had the issue resolved with the cleaning of the intake. Did you just complain about hesitation to the dealer or was the car actually throwing any codes. If it was just the hesitation did the dealer try to replicate the issue or did they just investigate it for you.

Just trying to figure out what I need to say to the SA exactly to get this resolved.

This thread has been helpful as it seems to be the issue I'm experiencing.

Repetative complaints. I had codes leading up to this (misfires, sticky vanos solenoid). Those resulted in new spark plugs, a couple of new vanos solenoids, new vanos bearing ledges). Those may have been legitamate problems that caused the codes though. In my last couple of visits, there were no CEL's, just an easy to reproduce shudder feeling with WOT.

Finally I had to say - you've changed plugs twice in the last few months. you've changed vanos solenoids twice in the last few months. These might be bad - but something else is making them bad. Please keep my car until you get it right!
And they did. It took a month, but they got it.

It sounded like this dealer wasn't that familiar with the problem. They had a BMW field engineer in twice to look at it before they came to this conclusion. Apparently a lot of labor is involved, so maybe they don't want to jump right into carbon scrubbing.
I suspect as more N54s approach 50K, the dealers will get very familiar with this issue.

[samej]

I recall seeing a video on how to clean your valves on E90 at one point - someone idling their car and spraying the cleaner directly into the intake hose. Too lazy to search.

The issue if I recall is that with direct injection the gas no longer washes the valves as it does with port injection, so carbon and gunk can build up over time. On the stem/top of the valves. Probably one of the engineering data points used by Lexus in their DI engine, which does both port and DI.

[JBurer]

Having the same issue with my car - looks like I'm not the only one.

http://www.1addicts.com/forums/showthread.php?p=7815964

Originally Posted by JJB

Repetative complaints. I had codes leading up to this (misfires, sticky vanos solenoid). Those resulted in new spark plugs, a couple of new vanos solenoids, new vanos bearing ledges). Those may have been legitamate problems that caused the codes though. In my last couple of visits, there were no CEL's, just an easy to reproduce shudder feeling with WOT.

Finally I had to say - you've changed plugs twice in the last few months. you've changed vanos solenoids twice in the last few months. These might be bad - but something else is making them bad. Please keep my car until you get it right!
And they did. It took a month, but they got it.

It sounded like this dealer wasn't that familiar with the problem. They had a BMW field engineer in twice to look at it before they came to this conclusion. Apparently a lot of labor is involved, so maybe they don't want to jump right into carbon scrubbing.
I suspect as more N54s approach 50K, the dealers will get very familiar with this issue.

JB, what dealer do you use here in Atlanta?

[JJB]

Originally Posted by JBurer

Having the same issue with my car - looks like I'm not the only one.

http://www.1addicts.com/forums/showthread.php?p=7815964



JB, what dealer do you use here in Atlanta?

Been back and forth between Global and United in Roswell. United is the one that finally fixed it.

[JBurer]

Same here.