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mike switzer
mike switzer,
Category: BMW
Satisfied Customers: 608
Experience:  lead diagnostic tech at Aamco
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2000 bmw 540 - Having. Rpm dip whencing to a spot, loss of

Customer Question

2000 bmw 540 - Having. Rpm dip whencing to a spot, loss of power and a low idle.
JA: Thanks. Can you give me any more details about your issue?
Customer: Replaced a lot of parts to hunt this issue down and am just throwing money at it. Guessing maybe a vanos issue
JA: OK got it. Last thing — BMW Mechanics generally expect a deposit of about $18 to help with your type of question (you only pay if satisfied). Now I'm going to take you to a page to place a secure deposit with JustAnswer. Don't worry, this chat is saved. After that, we will finish helping you.
Submitted: 1 year ago.
Category: BMW
Expert:  peterpete190 replied 1 year ago.

My name is ***** ***** I am a professional here at Just Answer. I noticed that your question had not received a response and thought I would see if you still need help with this.I apologize for the delay and I hope I can still assist you with this here.

If the check engine light has come on with this issue here the first thing that needs done is to have the fault codes read out/checked to see what codes are set.Once this has been done any codes set need diagnosed to locate and correct this isue here.If this has already been done and no codes are set let me know so we can continue here.

If more help is needed, use the reply tab to continue our conversation. If no further assistance is needed, kindly rate my service.You can rate at any time and we can continue to work on your question as this will not close out your question.Keep in mind in some cases it can be difficult to fully diagnose or help repair your vehicle without seeing it and I work on delivering the best possible answer from what I see to work with.

Thanks Pete

Customer: replied 1 year ago.
Having a dip in rpm when coming to a stop. No engine codes are coming up, changed a lot of parts to find the solution and haven't tackled it yet. Had a smoke test done twice to possibly find a vac leak, 3 full diagnosis at bmw on the big computer and everything is good across the board. New fuel pumps, filter, valve solenoids, intake manifold gasket, crank case vent valve and gasket, new spark plugs, new cam position sensors. I also did a throttle adaption reset and haven't had any luck yet.
Expert:  peterpete190 replied 1 year ago.

Was the throttle bore ever cleaned from any carbon build up at all?

Customer: replied 1 year ago.
You think it's a throttle issue more than a vanos or transmission problem possibly. I haven't had the throttle looked at really. I'm also getting s cold start rattle sometimes and the loud tick of the vanos seals going out. I'll have to check into that throttle cleaning. Does the unit have to come off the car to be cleaned
Expert:  peterpete190 replied 1 year ago.

The vanos is a common fault as well and if you have noise coming from it it may need replaced.I have seen issues with the throttle body being gummed up partially and can cause this here and cleaning it with a shop rag with some brake or carb cleaner sprayed on it can help clean it up for better operation.I would check into this as well to see if this resolves the issue.

Let me know if you need anything else and feel free to rate my help here.

Thanks Pete

Customer: replied 1 year ago.
I'll try that tomorrow for sure. Lot cheaper than a vanos seal and oring swap. Been quoted 1500$ from a few places Ouch. Lotta work
Expert:  peterpete190 replied 1 year ago.

Yeah they can be expensive to replace but is also another common fault here.If the carbon clean does not correct this fault here then I would have the vanos checked into to see if it is the cause needing replaced.

Thanks Pete

Customer: replied 1 year ago.
I cleaned the throttle body really good. Didn't see a change there. Any other ideas on what could cause that?
Customer: replied 1 year ago.
I cleaned the throttle body reaaaaallt well. No change in anything. Any other ideas ?
Expert:  peterpete190 replied 1 year ago.

I apologize for the delay.

Does it feel like the engine is bogging down at all when this occurs or when taking off from a stop at all?

Customer: replied 1 year ago.
Not nec at a take off, but maybe a little. I just took it to a mech yesterday who turned my idle up to 600 with a machine so the car isn't idling so low which makes the oil pressure lower. Even though the car is idling higher the car still says its idling at 4. Still dips down when coming to a stop, and the mechanic says he never saw it dip when he was test driving it? She they were done I picked it up and it was still dipping in idle every stop so I'm u sure why he can't see that. I have a video of it.
Expert:  peterpete190 replied 1 year ago.

This is a tough one for me to answer myself here.

I will open your question up for others here to see if someone else can assist further on this as there may be others here that may have more info on what to check or do with this issue.I hope you can get this resolved with ease.No need to reply to my last post here unless it is a last resort as it will keep your question locked to me and others will not be able to view it.If you feel you want to continue to work with me on this feel free to reply at any time but keep in mind in some cases it can be difficult to fully diagnose or help repair this without seeing your vehicle.

Thanks Pete

Expert:  mike switzer replied 1 year ago.

those cars have a problem with intake gasket leaks on the upper manifold i would replace the intake gaskets before proceding with anything else.

Customer: replied 1 year ago.
Replaced the intake manifold gasket and pcv valve and had the throttle body cleaned. Last month
Expert:  mike switzer replied 1 year ago.

ok i am sorry i read through the post did not see that. hang on one moment.

Customer: replied 1 year ago.
Waiting still man. Any ideas