[Pete.J]

My car is running the stock factory tune atm, and I am planning on getting an ECU tune sometime in the next month. Most likely it'll be AA tune because of its popularity between members on these forums.

Currently when accelerating I get a flat spot at around 3,000rpm. So below 3,000rpm there's plenty of torque and the car pulls fine, at around 3,000rpm it feels a bit flat and doesn't pull very hard, from around 3,700rpm-4,000rpm and all the way up to the redline the engine opens up and screams all the way up to the redline and pulls hard!

Now, does the AA tune get rid of that flat spot around 3,000rpm? Or at least mask it out a bit so it's not very obvious?

My car is an E90 6MT Euro 325i with the high output 2.5L version "N52B25 OL". We get the 3-stage intake, Euro airbox, and oil cooler as standard.

By looking at a few dyno graphs for the 330i with the high output version "N52B30 OL", there seems to be a dip in the power and torque curves at 3,000rpm! Which is exactly what I am feeling when I drive my car... Is this just caused by the DISA valves opening/closing? Or what causes this dip in performance?

Thanks in advance

[Taskmaster]

Originally Posted by pitos_7

My car is running the stock factory tune atm, and I am planning on getting an ECU tune sometime in the next month. Most likely it'll be AA tune because of its popularity between members on these forums.

Currently when accelerating I get a flat spot at around 3,000rpm. So below 3,000rpm there's plenty of torque and the car pulls fine, at around 3,000rpm it feels a bit flat and doesn't pull very hard, from around 3,700rpm-4,000rpm and all the way up to the redline the engine opens up and screams all the way up to the redline and pulls hard!

Now, does the AA tune get rid of that flat spot around 3,000rpm? Or at least mask it out a bit so it's not very obvious?

My car is an E90 6MT Euro 325i with the high output 2.5L version "N52B25 OL". We get the 3-stage intake, Euro airbox, and oil cooler as standard.

By looking at a few dyno graphs for the 330i with the high output version "N52B30 OL", there seems to be a dip in the power and torque curves at 3,000rpm! Which is exactly what I am feeling when I drive my car... Is this just caused by the DISA valves opening/closing? Or what causes this dip in performance?

Thanks in advance

Could just be the DISA changeover.

try resetting your adaptations and we can go from there.

[mmmnot]

Originally Posted by TheAxiom

Could just be the DISA changeover.

try resetting your adaptations and we can go from there.

Yes. This.

3K RPM is when the smaller valve (I believe) opens.

[Volasko]

The AA tune has been proven to improve the dead spot in our power curve when the DISA valves activate. I did notice this flat spot when I was stock it is basically gone with the AA Tune.

[Pete.J]

Ok, thanks for the replies everyone, I'll reset the adaptations and report back if the flat spot around 3,000rpm has been improved.

I am planning to get an AA tune very soon, may be in a month or two, just waiting for the Aussie dollar to get a bit higher coz atm I'll be paying close to $800 AUD for the tune.

I don't know how to reset the adaptations, so I'll be researching this today, I've got INPA, NCSexpert, winkfp and the OBD II diagnostic cable.. So it shouldn't be too hard to figure out hopefully

[mmmnot]

Originally Posted by pitos_7

I don't know how to reset the adaptations, so I'll be researching this today, I've got INPA, NCSexpert, winkfp and the OBD II diagnostic cable.. So it shouldn't be too hard to figure out hopefully

http://www.e90post.com/forums/showthread.php?t=544115

Try that first.

[Pete.J]

Originally Posted by mmmnot

http://www.e90post.com/forums/showthread.php?t=544115

Try that first.

Ok thanks, I'll give it a shot next time I jump in the car. If that doesn't work then I'll research "resetting the adaptations" and perform it.

If both solutions fail, I'll take off the 3 stage IM and clean it and make sure the DISA flaps are moving freely and operating correctly.

Question on the side:

Do N54/N55 oil catch cans fit our cars? Because I took my 3 stage IM off on my old auto E90 325i, and it had a layer of condensed oil on the walls that probably made its way to the 3 stage IM as vapour through the PCV. I'd want to install an oil catch can to keep the 3IM clean on the inside.

[hassmaschine]

if it's more than a light film then your oil separator is probably in need of a refurb.

[gunnerxq]

Originally Posted by mmmnot

http://www.e90post.com/forums/showthread.php?t=544115

Try that first.

This doesn't work for manuals right?

[Taskmaster]

Originally Posted by gunnerxq

This doesn't work for manuals right?

It should.

[thakid22]

Originally Posted by pitos_7

My car is running the stock factory tune atm, and I am planning on getting an ECU tune sometime in the next month. Most likely it'll be AA tune because of its popularity between members on these forums.

Currently when accelerating I get a flat spot at around 3,000rpm. So below 3,000rpm there's plenty of torque and the car pulls fine, at around 3,000rpm it feels a bit flat and doesn't pull very hard, from around 3,700rpm-4,000rpm and all the way up to the redline the engine opens up and screams all the way up to the redline and pulls hard!

Now, does the AA tune get rid of that flat spot around 3,000rpm? Or at least mask it out a bit so it's not very obvious?

My car is an E90 6MT Euro 325i with the high output 2.5L version "N52B25 OL". We get the 3-stage intake, Euro airbox, and oil cooler as standard.

By looking at a few dyno graphs for the 330i with the high output version "N52B30 OL", there seems to be a dip in the power and torque curves at 3,000rpm! Which is exactly what I am feeling when I drive my car... Is this just caused by the DISA valves opening/closing? Or what causes this dip in performance?

Thanks in advance

Vanos solenoids...
There are two of them inserted into the front of the engine on the cylinder head.
You have an intake solenoid and an exhaust solenoid.

As the engine ages, the solenoids do too. They can also get dirty. This causes them to be less effective, slow, and/or inaccurate throughout their range of operation. They can have quite the effect on performance without even throwing a CEL.

Symptoms are:
Poor throttle response. In consistent power. Bad mpg. Rough idle.

Solenoids can be cleaned for free. When you reinstall them, put them in the hole opposite where they came out of. Doing this made such a difference on my 330i @ 128k miles, I took the leap and bought brand new solenoids and installed them. The improvement was even more pronounced! At high mileage, I recommend replacing NOT cleaning them, because the solenoids degrade electrically. If you're on a budget, you can just clean them and switch them around upon reinstallation. But the parts are cheap enough to just replace them and be done with it.


No need to by BMW solenoids. I got mine from rockauto.com for a fraction of the cost of new BMW parts.

Search the forums for more info and to determine if this right for you.

[Ferdi_mruvkata]

Hello,

How have you solved actually the flat zone between 3000 and 4000rpm. A friend of mine and I are observing the same thing with our n52b25 motors.

Thanks