Acceleration surge

[salzki]

Hi guys so recently I've been experiencing this rather odd behaviour from the car (E60 N52 530i LCI). Okay let me give you a scenario:

Let's say I'm cruising at 60km'h and I wanna give the car a little push so what do I do? I give the accelerator pedal abit more push so the car can accelerate. So here comes the odd part, the car actually surges and lost power for a split second and then it started accelerating.

Only happens when I wanna give it a little more acceleration from a cruise, no such problem if I'm in Sport mode.
This usually happens more often (8/10) if the car is still cold/after I left it for quite sometimes. Once it's warmed up, probability of it happening is 3/10.

So I've asked my mechanic regarding the issue and they couldn't really find any problem with it, hmmm. I searched up online and there are quite a few possibilities leading to this behaviour.

1. It could be that I needed a new atf oil.
2. One of the solenoid could be on its last leg.
3. Many more gearbox related issue.

At the moment it hasnt shown any error codes and the fact that I can still drive the car normally, it kinda scares me.
I wanna fix this before anything else fails, I'm all in for preventive maintenance.

Hope you guys can chime in and share your opinion or maybe past experiences regarding this issue, really appreciate it.

UPDATE (29/9):

So I finally went to my mechanic and got it checked out, they discovered a VALVETRONIC fault code so they proceed to diagnose it.
After 1.5k of parts & labor, it finally runs good now! They replaced the VALVETRONIC motor and the windshield washer motor since it was leaking too.

UPDATE (4/10):

It was all smooth and fine until recently the problem came back again. I've checked my plugs and still good, not sure bout fuel filter. But what's odd is that it was giving the valvetronic motor code, nothing else. I'll send it to my mechanic again to check for the new fault codes. This is pretty infuriating. Welp, there goes my 1.5k

LATE UPDATE: (17/2): Issue is resolved!

 

[Herbert]

Replace the ATF filter & fluid first. If the issue is still unresolved, then most likely is the mechatronics solenoids.

 

[salzki]

Replace the ATF filter & fluid first. If the issue is still unresolved, then most likely is the mechatronics solenoids.

Thanks for the tips, I'll get it done as soon as I have time.
Do you have any idea how much would those mechatronics go for? All I heard was that the transmission is the most expensive part of the car.

 

[kevin1982my]

Its not easy to diagnose something on a forum.

It could very well be fueling or ignition related.

When was the fuel filter last changed? Spark plugs?

I have had similar surges and power lost before in my BMW and other makes that was attributed to the above 2.

A buddy's car was hesitating and Vanos seal was the culprit.

 

[salzki]

Its not easy to diagnose something on a forum.

It could very well be fueling or ignition related.

When was the fuel filter last changed? Spark plugs?

I have had similar surges and power lost before in my BMW and other makes that was attributed to the above 2.

A buddy's car was hesitating and Vanos seal was the culprit.

You are right, I'll look up my service history again.
I forgot to mention that I've left this car in the garage for more than a month since I had to go overseas, gonna diagnose the car as soon as I have the time.
Anyways, thanks for the tips.

 

[Herbert]

Thanks for the tips, I'll get it done as soon as I have time.
Do you have any idea how much would those mechatronics go for? All I heard was that the transmission is the most expensive part of the car.

The 7 pieces of ZF solenoid from Bavaria Auto is about RM 1.3k. You will also need to buy 8 litres of ZF ATF oil plus ATF filter. Labor charge would be about RM 600.

 

[salzki]

Problem still unsolved, updated original post.

 

[salzki]

Went back to mechanic and can't find the problem. No fault codes or anything but the surge is still there...

 

[beemerback]

Try another mechanic.

 

[321aisyalam]

Hi salzki,

I agreed with beemerback. Please seek second option. It will be good if the mech can do a diagnostic, swap the suspected faulty part with a working part. Retest again before recommend you to replace any part. So you will not spend for unnecessary part. Optimum did that for me during my car has solenoid valve issue. Anyway mine is n52 - 525. Maybe your 530i hard to get the identical part due to rarity.

 

[salzki]

Try another mechanic.

Yes I'd do so for sure, just looking for the right time to do it.

Hi salzki,

I agreed with beemerback. Please seek second option. It will be good if the mech can do a diagnostic, swap the suspected faulty part with a working part. Retest again before recommend you to replace any part. So you will not spend for unnecessary part. Optimum did that for me during my car has solenoid valve issue. Anyway mine is n52 - 525. Maybe your 530i hard to get the identical part due to rarity.

Yes, if part is available it's gonna be so much better but I guess it all comes down to the mechanic itself. I mean how they handle with all these stuff. I am gonna go to another mechanic to look at, checking out list of workshops now and see which is close to my place. Really appreciate your input.

 

[harry_7]

My scenario might be similar with your, I had changed valve body solenoid once at 120k km. After clocking another 80k km, the whole GB overhaul. After that, found the power is less than previous time (car can drive until 160km/h, cannot go further), then replace the torque converter, now everything smooth... Different car has different issue, might need to check properly....

 

[salzki]

My scenario might be similar with your, I had changed valve body solenoid once at 120k km. After clocking another 80k km, the whole GB overhaul. After that, found the power is less than previous time (car can drive until 160km/h, cannot go further), then replace the torque converter, now everything smooth... Different car has different issue, might need to check properly....

Last week my mechanic (new place) found there's the camshaft sensor (exhaust) code when they were running diagnostic. Cleared it, went for a test drive, came back to check and it's gone. Then last Saturday went there to check again and the same code appeared again. I'm suspecting this might be the culprit and asked mechanic if it is, they told me there's a possibility but not 100% sure.

 

[salzki]

Looks like I might need a valve cover job. When I opened the oil fillr cap, there's some resistance to it however that's the only thing I'm having right now (on top of the camshaft sensor).

 

[salzki]

Turned out it wasn't valve cover, it was my DISA flap that broke. Replaced it and together with all my spark plugs (condition got very terrible compared to 3 months ago when I inspected). Cleaned and swapped my vanos solenoid too, everything is smooth for now.

 

[salzki]

Late update: Hesitation/surge is gone, what I did was clean up the VANOS solenoid and change the oil. Car runs smooth and no more hesitation.