Sluggish E39 530i motorsport

[speedyg 16]

Hi,

My recently purchased 530i Touring is feeling really sluggish low down in the revs. Since buying it I have always thought that it felt a bit slow as I also have a 530i motorsport sedan (that I am trying to sell) Today I went for a good drive in the sedan after having not driven it for a while. The cars are like night and day, the sedan is so much quicker low down in the revs. I know the Touring is a little heavier but it shouldn't be that much different. I have recently done the vanos with new Besian seals, so I know it's not that, I disconnected the MAF sensor which didn't make much difference, so I suspect that's ok, what's next cam sensors?

I did a few tests in the Touring today:

0-80kph: 8.2secs with MAF disconnected and 7.5 with it connected

0-100kph 10.7 secs with MAF disconnected and 10.0 with it connected.

Factory stats are 0-100kph 7.9 secs

Tommorow I'll time the sedan for a comparison.

It feels good once the revs get over 3000rpm but just bogs down off the line, no way could you get any wheelspin with the traction control off.

Any ideas?

I had it scanned a month ago and there were no fault codes.

Thanks.

Edited August 18, 2012 by speedyg

[_ethrty-Andy_ 2132]

just an idea as i dont really know the engine, but did you reset the ECU codes after you did the vanos seals? prehaps the ECU adapted to the old busted ones? older engines like M50 M40 M20 did that obviously no vanos involved but adapted to other issues etc

[speedyg 16]

just an idea as i dont really know the engine, but did you reset the ECU codes after you did the vanos seals? prehaps the ECU adapted to the old busted ones? older engines like M50 M40 M20 did that obviously no vanos involved but adapted to other issues etc

Yeah good thought, I haven't reset so possible I guess. Thanks

[Allanw 1071]

Run high octane (you probably are anyway)

Have you checked the DISA valve. They can destroy engines anyway, so worth doing, but they can also tear membranes and not work, taking away a good wollop of low end torque.

Looking at the engine from the front, it's just behind the throttle body, screwed (torx) inthe the right hand side of the intake.

They're a pretty common failure, with a bit of milage on. Certainly worth looking at anyway, as if it comes apart, the pin in the end can get eaten by a cylinder = poked engine.

You can get a kit online to repair them with cnc machined replacement components, or you can buy a replacement genuine item. If the vacuum side of things is poked, you have to buy a new valve anyway, but you can still update it if you want.

Mine had a leak across the membrane, which I fixed and noticed a small increase in low end torque, although it was probably working to some degree with the leak. Usually, pulling them apart screws them completely, in typical BMW fashion! The actual mechanical parts were perfect though.

DISA Valve check and repair kit

[speedyg 16]

Thanks, I was just reading about the DISA valve. Sounds like it would be worth doing anyway for the sake of $115! I'm guessing you just got the kit from the states?

[speedyg 16]

I did a few tests in the Touring today:

0-80kph: 8.2secs with MAF disconnected and 7.5 with it connected

0-100kph 10.7 secs with MAF disconnected and 10.0 with it connected.

Factory stats are 0-100kph 7.9 secs

Tommorow I'll time the sedan for a comparison.

Tested the sedan today:

0-80kph: 6.3secs

0-100kph 8.0secs

So that will be why I can feel the difference.

[Allanw 1071]

Thanks, I was just reading about the DISA valve. Sounds like it would be worth doing anyway for the sake of $115! I'm guessing you just got the kit from the states?

I'd like to fit the kit one day, But as I say, mine is perfect as far as the worn out parts go. I'll keep an eye on them. I wonder if mine was always leaking from new, and that's why the flaps wasn't worn at all - any time it did change, it would have done it slower and less abruptly.

I wonder if the 2 cars have the same diff ratio. Some markets had different ones spec'd and sometimes "Motorsport" cars had shorter final drives to pep them up.

[speedyg 16]

I'd like to fit the kit one day, But as I say, mine is perfect as far as the worn out parts go. I'll keep an eye on them. I wonder if mine was always leaking from new, and that's why the flaps wasn't worn at all - any time it did change, it would have done it slower and less abruptly.

I wonder if the 2 cars have the same diff ratio. Some markets had different ones spec'd and sometimes "Motorsport" cars had shorter final drives to pep them up.

When you pulled apart the DISA, how fragile is it? I want to pull it off but my wife uses the car daily and I don't want to break anything, if it is easy to get off without damaging anything ie the rubber seal, I might whip it off and have a look and if necessary swap the one of my other 530i. I might do the same with the cam sensors. That way it won't cost anything and hopefully I can eliminate a few things.

If that fails I will take it in to get it scanned.

[smiddy 76]

I would be reluctant to start swapping parts. Especially before a scan.

[Allanw 1071]

When you pulled apart the DISA, how fragile is it? I want to pull it off but my wife uses the car daily and I don't want to break anything, if it is easy to get off without damaging anything ie the rubber seal, I might whip it off and have a look and if necessary swap the one of my other 530i. I might do the same with the cam sensors. That way it won't cost anything and hopefully I can eliminate a few things.

If that fails I will take it in to get it scanned.

Pull the unit off complete. Normally, if it's broken anywhere, you can't realistcally fix it (I was lucky!). only takes a couple of minutes to get out

buy a scan tool you can still drive it in the meantime, and $40 isn't too bad for a scan tool. Visit My Website

[speedyg 16]

Pull the unit off complete. Normally, if it's broken anywhere, you can't realistcally fix it (I was lucky!). only takes a couple of minutes to get out

buy a scan tool you can still drive it in the meantime, and $40 isn't too bad for a scan tool. Visit My Website

Does anyone else have this scanner, sure seems cheaper than paying $50 to get the car scanned.

I will hopefully get a chance to get under the bonnet this weekend.

Also I forgot to say along with the lack of power the obc is reading 16L per 100kms! So slow and thirsty, not a combination I like.

[speedyg 16]

Just to update this, the car is now fixed.

The problem turned out to be a jammed exhaust vanos solenoid piston. In the end a 15 minute job, I took the solenoid off, pushed the piston that it pushes in and out a bit, it felt a little sticky, so I took it out and cleaned everything up, reoiled and put it back together. Car now has heaps of low down power.

The hardest part was finding the tube spanner to get the solenoid off.

[Allanw 1071]

Just to update this, the car is now fixed.

The problem turned out to be a jammed exhaust vanos solenoid piston. In the end a 15 minute job, I took the solenoid off, pushed the piston that it pushes in and out a bit, it felt a little sticky, so I took it out and cleaned everything up, reoiled and put it back together. Car now has heaps of low down power.

The hardest part was finding the tube spanner to get the solenoid off.

Sweet! Good to here it was "easy" and cheap!

It's impressive how much difference the Vanos makes.

[speedyg 16]

Drove the car today and it's back to being sluggish, well at least I know what the trouble is. I will pull it apart again and re clean and look for any rough edges on the piston or cylinder.

[Allanw 1071]

Make sure the "filter" gauze in the feed to the solenoid is clean too

[speedyg 16]

Get someone who knows what they are doing to check the MAF output voltage.

They do strange things.

Car is running great now, re did the solenoid piston and all good so far. Feels like a different car. Definitely worth checking if you think your car (M54) is feeling sluggish under 3000rpm.

[benpaul12 62]

Has anyone else done this clean of the VANOS solenoids recently?

Seems like an easy clean and may fix my 1300-2000 RPM minor-surging and fluctuating idle.

Speedyg, has this lasted?

[_ethrty-Andy_ 2132]

Has anyone else done this clean of the VANOS solenoids recently?

Seems like an easy clean and may fix my 1300-2000 RPM minor-surging and fluctuating idle.

Speedyg, has this lasted?

scanning it first is always going to be the best first step

[KwS 2425]

you should be able to test the vanos solenoids with a scanner too

[benpaul12 62]

^ excuse my ignorance but what are my options around getting a scanner? Also, how much does a diag scan cost at the local mechanics these days? I remember when they were $250!

[speedyg 16]

Has anyone else done this clean of the VANOS solenoids recently?

Seems like an easy clean and may fix my 1300-2000 RPM minor-surging and fluctuating idle.

Speedyg, has this lasted?

Hi, Yes car is still going good, it was definitely a quick and easy fix, the hardest part is find the right size tube spanner.