Happened to me just after I bought my 04 ZHP. It would hesitate between 2500 and 3000 under moderate acceleration and usually pulling a grade. It was more noticeable in 5 and 6th gear. The dealer had to re program the ECU. Everything is fine now and pulls like pissed of bull. I was under warranty so they did it for free.

 

+111 This was the exact issue with my ZHP and a ECU flash fixes the power hesitation.

Edit: Also look into Vanos seal repair as this is also a culprit.

 

Ignition coil pack or sparkplugs? Possibly vanos. Have you checked?

 

thats wat I said it would be too, but they said that they would have to let the BMW rep see the car first. It only jerked a little, not too noticeable right?
How long did it take for them to reprogram the ECU?

 

That happens to me when I take off in 1st gear and I feather off the gas a little bit. I felt maybe it was just normal due to it being stick. Maybe it could be something else?

 

Normal, load shifting from engine to drive train to drive train to engine. In other words, thats called engine breaking. kinda.

OP, and others, How old is your clutch and how high up is your engagement point?

 

Not quite sure, cause I dropped the car off in the morning and picked it up after work. I believe if you have a CPO they should provide a loaner, but you probably ought to call in advance to reserve one.

 

when you had the problem did it only happen after the car was warmed up? or did it happen when u drive it before it warmed up?

btw thanks for all the replies thanks....

also i didn't check the sparks or the vac lines...

 

Cam position sensor?

 

I had a problem similar to what you described. It turned out to be a single spark plug boot.

 

There is a well known issue with a power dip at 4000RPM in the ZHP's.
http://forum.e46fanatics.com/showthread.php?t=541059&highlight=4000+rpm+power
http://forum.e46fanatics.com/showthread.php?t=555570&highlight=power+dip
Maybe this is your issue?

 

No I dont get the RPM dip....but the studdering....Some other members have had this issue as well...I found this post:
http://e46toronto.ca/forums/showthread.php?p=106563 am

I got my car back today and they said they can't fix it, and I should contact BMW of NA...which is bullSHI*
Im so tired of trying to go through all this red tape to get something done for my car...when they acknowledged that something is wrong. They said that BMW of NA have to approve the ECU upgrade. Anyone knows how I can resolve this w/o making 20 phone calls to speak to someone?

BTW: thanks for all the input...

 

Also experienced the same issue with my 04330cizhp6sp, jerky acceleration ... Check the vehicle maintenance history at BMW and if the DME has not been re-programmed (this would be recorded in the database) then you should investigate BMW4ME's suggestion. See attached link to the TSB. BMW will repair free of charge and it will take about 1 week. Take a copy of the TSB because the SA's and tech's will likely not be familiar with the problem as it is unique to your car (6spzhp) and year. My local dealership also pleaded ignorance but were happy to resolve the issue after I provided a copy of the TSB. Good luck.

http://www.employees.org/~amoeba/img/SIB121705.pdf

 

Did you get the jerking at 4000rpm or between 2500-3000RPM, also did it get worse with the car warmed up?

Also when was your car manufactured? B/c mines was August 04, so it may have the software update.

 

Did you get the jerking at 4000rpm or between 2500-3000RPM, also did it get worse with the car warmed up?

On mine, it was most obvious when the outside temps were warm, the A/C was on, and the car loaded with passengers - but it would do it other times as well. Basically the high temps and high load on the engine forced more timing to be pulled when passing through the 4000 rpm range. I never revved my car high enough to exhibit this problem until the motor was thoroughly warmed up so I can only say that it occurred when the motor was up to full operating temperature.

 

I don't experience problem at 4000rpm (much talked about in other threads), so I am not sure its the same problem. I get no dip in power but a jerk, like the car is stuttering during acceleration. Did you get the stuttering or the Dip in power at 4000rpm. Also did it specifically happen at 4000rpm or at 2500-3000rpm? thanks

 

Mine was consistently in the 4000 - 4500 (approx) range and it was a very sudden loss of power which would jerk your head around when it happened.

I don't recall anyone reporting this, or any other problems, specifically in the 2500-3000 rpm range. Except for the rpm range though, your description sounds exactly like the 4000 rpm problem. If your DISA valve were exceptionally "noisy" from the perspective of the knock sensors, I suppose the DME could have adapted to pull timing at a different range.

If it's not a software issue, I would be most suspicious of bad coils. There was a recall on the Bremi coils (my 2004 was affected, had them replaced with Bosch). You might see if your dealer can verify whether your car was part of this recall and that it now has the Bosch ignition coils.

 

Ohh there was no stuttering...just a jerk...b/c I feel multiple jerks when accelerating in mentioned RPM range. I don' think its the coils because it only happens in these RPM ranges, btw when was your car produced. Mines was in august of 2004, so I am not sure mines had the recall. Also, Thanks for your help. I appreciate it!

 

My car built in 02/04, don't remember the date range for the recall.

Does it seem to matter what gear you are in?

 

car jerks

Check your coils one of them is faulty

 

Kpbus, f it was the coils shouldnt it be seen in all RPM ranges?

Also I notice it in 3rd,4th,5th, and 6th. It is most noticeable in 3rd and 4th.
The problem is that I had my car looked at by the BMW Rep, and they were unable to reproduce the problem, or so they say. I checked my odomater, and he only drove it for 3 miles, and the car was probably cold, therefore there was no way he could have felt it. The car NEEDS to be fully warmed up for it to be noticed.

TxZHP, did yours happen in the gears I mentioned or in all gears?

 

I have a non-ZHP 330ci with the 6speed. Build date is 5/03. I was experiencing something similar last summer...as if the car was doing a tug-of-war with some invisible force. It was across all the gears at different RPM range. I swapped my coils, changed my plugs, and replaced my o2 sensors. I also had a CEL due to the o2's because the coils and plugs did not get rid of the problem, but the issue was there even before the light came on. I did have the recalibrated ECU update, which removed my Dinan software, but that did not work for me. Good luck either way. I think it may be your o2 sensors though. I'd start with the ECU recalibration, then plugs and coils, and finally with the o2's...pre-cat most likely depending on yor mileage.

 

Mostly in 2nd and 3rd, don't remember about 4th (it's been a couple of years now)... not sure I ever tested it in 5th and 6th as I'd be doing 100 or more in those gears at 4000 - 4500 rpm.

 

TxZHP...thanks for the help though...btw the changes you felt was it consistent at 4000rpm,always or did it depend on how you drive the car etc?

ari00, i think I will get those items checked if and ecu flash does not fix the problem.

 

I GOT IT FIXED. Bmw did a test on my ecu or something and they found something wrong with the program (dealing with the first ecu sensor). I will do a full write up later. But the reprogrammed the ecu to fix it. thanks for all the info from everyone who replied.....

 

Can you post a scan of the service invoice? I have this exact problem with my ZHP (jerky acceleration between 2500-3000 revs), and I'd rather not get the runaround from my dealer.

 

Better off PMing the person. This thread is over a year old.

 

oh damn I read that as 2009; yea I'll do that.

 

Can anyone do a full write up on the issue and how to fix it? I notice jerking/hesitation in 2nd and 3rd gears, and need to fix it!

Thanks fellas!

 

Bump. I'm having the exact same problem. Hesitation between 2500-3000 in all gears. 330ci 6spd non-zhp. There must be a solution to this. I've seen a bunch of posts about it but no solid answers.

 

When i had this problem it turned out to be a bad ignition coil.