E46 Idle dip

[Iceman007]

I had this idle dip for almost a year now and cleaned and checked for vacuum leaks and found nothing. Then I went back in my cars history and found that my problem started not long after I changed my alternator regulator with a pirate one and not a bosch on. So I went into my board computer function 9 and watched the voltage while i drive and it would peak at 14.5V and dip as low as 13.5V with no load on. and if I switched on load like Aircon etc it will dip as low as 13.2V. Eventually I decided to change my Alternator regulator again with a genuiene Bosch regulator after reading some posts where the Dealers replaced the Alternator after such a occurance.

Now the Voltage stays more constant at 14.2V and only dips as low as 13.8V with load, The and max ive seen is 14.3V but on avarage it will be 14.1V to 14.2V. And yes the Dip and hunting in Idle I had is gone. mine was quite bad for it would dip and keep hunting untill I reved it while stationary sometimes. Ive checked my voltage on the dash and also it would run up and down like it battels to regulate constantly.

Something to look at

---

The Voltage 14 t0 14.2 is correct

this is what my car did more or less it just did not cut out on me.

I have also replaced my Vanos seals with the Beisan make http://www.beisansystems.com/ . Man what a differince not in performance only but when pulling away. I dont have to rev it up to 1200rpm anymore, which i had to do since I bought the car at 80k. I can pull away normally now. The O Rings that were in there were hard as plastic and the piston fitted loosely 151k on the clock. And they say these O-rings go plastick at 35k already. Its worth changing them.

 

[Epoc]

@Iceman007 ... thanks very much for the info. I will contact my dealership now to let them check that out. My car has been with them for about 2 weeks now and 5 other occassions but they still can't sort the problem out.

My problem also started after they replaced the alternator.

Excellent hope this sorts my problem out ...

---

@Iceman007 ... thanks very much for the info. I will contact my dealership now to let them check that out. My car has been with them for about 2 weeks now and 5 other occassions but they still can't sort the problem out.

My problem also started after they replaced the alternator.

Excellent hope this sorts my problem out ...

@Iceman007 ... I have just contacted my dealership mech and he says the alternator unit is one sealed unit together with the regulator?

Any ideas?

 

[Iceman007]

I got my first lead of this post E46 Fanarics read the posts by Matti that is how his problem was fixed by changing the whole alternator
http://www.e46fanatics.com/forum/showthread.php?t=135677&page=5

Post 86 to 89 but read the whole thing to get an Idea of what can cause the problems on BMW engines. I also had a stalling problem when I pulled away when I got the car. I told the after the 3d visit under motor plan I suspect a filter and they told me cant be its "Liftime"
So I secretly did it myself and yes it fixed the problem

How can you drive 25k before an oil change(no wonder they have to as they call it flush the engine because of sluge buildup) and lifetime(not your lifetime but the liftime of the part) for fuelfilter Diff oil and gearbox oil. They want your car to break so you can buy a new one or make money from spares when out of warrenty. They know how to catch people thats not clued up on engines and cars so they can make money,

---

@Iceman007 ... thanks very much for the info. I will contact my dealership now to let them check that out. My car has been with them for about 2 weeks now and 5 other occassions but they still can't sort the problem out.

My problem also started after they replaced the alternator.

Excellent hope this sorts my problem out ...

---

@Iceman007 ... thanks very much for the info. I will contact my dealership now to let them check that out. My car has been with them for about 2 weeks now and 5 other occassions but they still can't sort the problem out.

My problem also started after they replaced the alternator.

Excellent hope this sorts my problem out ...

@Iceman007 ... I have just contacted my dealership mech and he says the alternator unit is one sealed unit together with the regulator?

Any ideas?

---

Yes under warrenty they replace the whole unit and dont open things up. my e46 is on my 3d Diff. The one they put in first lasted me only 2000km and I started getting a cluck noise in corners. so once again they said it cant be the diff so they replaced everything around it my propshaft side shafts and diff bushes. I did not complain its all new and eventually they replaced the diff again and problem solved. Lucky me now I had a coplete new drive train except gearbox. BMW dont listen to peoples advice the think there computers are clever and there mechanics with 2 years experiance are clever.

If you have electrical problems and even VNA and Tygervalley send cars to him is Combined Electronics in Plattekloof tel 021 930 3549

Sparxx sells them loose and complete Alternators bosh at half the pryse the agents asks. Tel 0219826811

 

[Epoc]

Cool thanks for the info ... will read up now ...

 

[Iceman007]

Epoc just for info also check your Battery voltage it should be atleast "minimum" be 12.5 after the car is switched off for 5 min. you can check it on your hidden functions on your onboard computer. Also make sure they did not damage one of your vacuum pipes when they replaced the alternator because the cable and battery light wire runs in the vicinity of one of the rubber hoses that comes from the oil seperator

I have an e46 2003 325i what is your model?

 

[Epoc]

Epoc just for info also check your Battery voltage it should be atleast "minimum" be 12.5 after the car is switched off for 5 min. you can check it on your hidden functions on your onboard computer. Also make sure they did not damage one of your vacuum pipes when they replaced the alternator because the cable and battery light wire runs in the vicinity of one of the rubber hoses that comes from the oil seperator

I have an e46 2003 325i what is your model?

It's gonna be a bit difficult cos the car is still with the stealership. But I have told them to check the voltage etc. The mech was pretty open to accept tips cos they are bewildered.

If i am not mistaken they have replaced the crankcase intake pipe or something like that ...

I have the same model just 2004.

 

[Iceman007]

Oh Ok so they have looekd for vacuum leaks because that is what they have to look for first. But if all this has happend after the alternator change I suspect the same case as mine. Let me know if they fixed the problem and if the alternator was the cause like in my case. Thats how we get to know our cars better and help each other out by solving symptoms like these. Thats why I also bought my own diagnostic software and cables to make sure its not somthing else causing it. My car is now error free and I check it every month

As I sead I drove for 1 year like this trying everything and thought it could not be the alternater affecting the DME and that BMW has put something in place to counter this from affecting your DME.

Nice Car the 325 just wish mine had a 6 speed box aspecially after the Vanos seals replacement. what a differince

 

[kevin23]

Ive got a similar problem with my E36 M3. When i stop the idle dips down and sometimes it cuts out. Do you think it can be the same problem??

 

[Iceman007]

Usually when they cut out on e46 it can be
1. ICV
2. Vacuum leak
3. Vanos and Vanos solenoid
4. cranck sensor
5. and cam intake/exhoust sensor
6. or O2 sensor(Take note vacuum leak can also cause False O2 sensor errors)

For some reason on the 3L e36 models the vanos tend to pack up first, but thats why cheapest get diagnostic done first this will eliminate all sensors and DME. Computer does not see Vacuum leaks ICV(give it a good clean there lots of posts on the net for this) and in some cases Vanos( will see only if its stuck in a position)

If you have never removed and cleaned the ICV then its the no 1 culpred

 

[Epoc]

Oh Ok so they have looekd for vacuum leaks because that is what they have to look for first. But if all this has happend after the alternator change I suspect the same case as mine. Let me know if they fixed the problem and if the alternator was the cause like in my case. Thats how we get to know our cars better and help each other out by solving symptoms like these. Thats why I also bought my own diagnostic software and cables to make sure its not somthing else causing it. My car is now error free and I check it every month

As I sead I drove for 1 year like this trying everything and thought it could not be the alternater affecting the DME and that BMW has put something in place to counter this from affecting your DME.

Nice Car the 325 just wish mine had a 6 speed box aspecially after the Vanos seals replacement. what a differince

Yip the guys are currently doing the vacuum test again to try and find a leak. Well I hope the Mech took your advice I gave him and is checking it out but will keep the thread updated with the results.

BTW which and how much and where from did you buy your diag software and cable?

Coming from a turbo diesel with 6 speed previously I would defintely also have liked the same on the 2.5. How did you know that your vanos seals needed to be replaced? Did that show on your diag software?

 

[Iceman007]

Well firstly why do I have to rev up a car to 1100rpm to pull away(my Honda 160i can ease off without touching the petrol) and why do you have to have a hessitation when you punch the peddal to the floor. And yes the seals are hard as plastic. they go hard after 30k and I believe that. Its worth Changing them. BMW wont even know but you will feel it

---

It will be iteresting to se the result if they change the alternator again. It worked for me and im driving for a week alreaydy no problems:clap:and very happy Keep us updated

 

[kevin23]

Thanx il take it in and get the computer plugd in and see what it says.

 

[Iceman007]

Thanx il take it in and get the computer plugd in and see what it says.

I pair R2000 for it 3 years back Carsoft6.5 from Direct Data. Not the best but it will tell you what you need to know + earase faults. The Ideal would be the GT1 software and cable but its expensive

 

[Lev]

@Iceman007, our 2003 E46 325i has a problem sometimes, it starts, the idle is rough and it refuses to accelerate properly (if we drive it, it feels like its in limp mode) and then cuts out and refuses to start at all.

When it does start (which is most of the time) it runs normally but the idle is still not smooth, you can feel the car is shaking a bit.
We checked the ICV (unplugged it) and the car started but it wouldn't rev, the behavior of the motor however with the ICV dis-connected is not what we experienced as described in the first paragraph.

Do you have any ideas?

 

[Iceman007]

@Iceman007, our 2003 E46 325i has a problem sometimes, it starts, the idle is rough and it refuses to accelerate properly (if we drive it, it feels like its in limp mode) and then cuts out and refuses to start at all.

When it does start (which is most of the time) it runs normally but the idle is still not smooth, you can feel the car is shaking a bit.
We checked the ICV (unplugged it) and the car started but it wouldn't rev, the behavior of the motor however with the ICV dis-connected is not what we experienced as described in the first paragraph.

Do you have any ideas?

Firstly you need to do a diagnostic and iliminate as much electronics(coils, vanos solenoids, O2 sensor, Disa Valve, Airflow meter, ETC) as possible. Then move to the mechanical like Vanos, Vacuum leaks abd so on. Beleive me if your Vanos seals are replaced you will have much much smoother excelleration and idleing. Just ask the people who have done it already they will all tell you the same. If your car is cutting out and the routgh idle it could be a combination of things.

Its not possible to do a diagnostic over the net and not seeing the car

 

[Lev]

@Iceman007 Thanks will run through these options and try to eliminate as much as possible.

 

[Iceman007]

Is your car fixed?

Oh Ok so they have looekd for vacuum leaks because that is what they have to look for first. But if all this has happend after the alternator change I suspect the same case as mine. Let me know if they fixed the problem and if the alternator was the cause like in my case. Thats how we get to know our cars better and help each other out by solving symptoms like these. Thats why I also bought my own diagnostic software and cables to make sure its not somthing else causing it. My car is now error free and I check it every month

As I sead I drove for 1 year like this trying everything and thought it could not be the alternater affecting the DME and that BMW has put something in place to counter this from affecting your DME.

Nice Car the 325 just wish mine had a 6 speed box aspecially after the Vanos seals replacement. what a differince

Yip the guys are currently doing the vacuum test again to try and find a leak. Well I hope the Mech took your advice I gave him and is checking it out but will keep the thread updated with the results.

BTW which and how much and where from did you buy your diag software and cable?

Coming from a turbo diesel with 6 speed previously I would defintely also have liked the same on the 2.5. How did you know that your vanos seals needed to be replaced? Did that show on your diag software?

 

[Epoc]

Not yet hey. BMW SA has sent Forsdicks a different gauge to test engine compression and to try and find if there is a vacuum leak.

Damn am I missing my car ...

 

[Iceman007]

Demand a courtesey car that speeds up things(refuse to leave the workshop before you have a courtesey car or yours fixed) Pitty its a bit of work then I could have showed them my car with old pirate regulator and now that its right with the new regulator. It would be interesting to see what your regulator peaks at and what the minimum is when the idle dips, its easy to see on the hidden functions on your dash(function 9)

 

[james]

I had a similar experience when I bought my car. 2 bottles of injector cleaner cured it.