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sebastian manrique
sebastian manrique, Auto Mechanic
Category: Car
Satisfied Customers: 456
Experience:  Director Ejecutivo at Multiservicios Cruz de las Mercedes
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I have a 3.20i 2005 e90 BMW automatic. I noticed that

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Hello,
I have a 3.20i 2005 e90 BMW automatic. I noticed that sometimes when am in slow moving traffic and in drive as soon as I brake the rpms go down and it’s like the car is about to stalll but then regains it’s self and is fine. The car drives well and this doesn’t happen often but has happpend. No check engine light, took the car to my mechanics and they couldn’t find anything, they said if it was the torque converter problem would get worse. As mentioned car drives fine, but this issue happens sometimes and they have looked at it but didn’t find anything. Can this happen sometimes with automatics?

Hello, I am Jose Sebastian. Your mechanic automotive expert, It's a pleasure to me to attend your question. Thank you very much for trust in just answer.

Dear customer, I would like to know, what mileage does your car have? And did the garage scan your car with an BMW diagnostic scanner?

Thanks.

Customer: replied 1 month ago.
Mileage is 83k yes they did and nothing came up on the scanner
Customer: replied 1 month ago.
Are you avaible?

Yes dear customer, sorry for my delay, what kind of fuel does your car use? Thanks

Customer: replied 1 month ago.
Petrol

Thanks dear customer, i will be back in a moment. i am finishing with the query of another clustomer and then i will be back to you.

Dear customer, these problems are related to the minimum or the idle speed which comes or is regulated by the throttle body system. So, this is the aspect that we must first look at

I recommend you to first go to a BMW garage with a BMW automotive scanner (others scanner sometimes does not show the error codes) with which you can watch the error codes and check the car operation in search of a part that is not working in a proper way. It usually is easily solved by performing a maintenance. because it accumulates a lot of dirt and the throttle body (butterfly) starts to stick with its components

sebastian manrique and other Car Specialists are ready to help you

If you observe that everything is correct in the Throttle body we proceed to check the injection system, checking the fuel pressure which is also observable through the scanner or with a gas pressure gauge.

If you have a lot of time without giving maintenenance to the injectors and you recently replaced the spark plugs, I recommend you do this soon.

The aspects mentioned above are the main causes of this kind of problems. another aspect is a major fault that could come from the engine which you can rule out by corroborating that the engine does not have strange noises and that the compression in the cylinders are equal for all.

Finally, if you do not have problems starting the car but only when it is idling, in my opinion we can rule out the torque converter. Anyway, with the scanner, we can observe If there are error codes referent to it.

Dear Customer, Is your inquire clear or is there anything else i could help you?
My goal is to give you the best advice I can and I hope that I've helped today. Please remember to rate my service by selecting from the 5 stars at the top of the screen before you leave. because in that way you help me grow in the platform and if you wish you can let a comment for the service and a tip.
Regards.

Customer: replied 1 month ago.
thanks for your response these are clear. We changed the spark plugs at the last service.
Customer: replied 1 month ago.
The car doesn’t have problems starting and drives very well.

Great dear custome, I am glad it is sorted out. Please remember to rate my service by selecting from the 5 stars at the top of the screen before you leave. because in that way you help me grow in the platform and if you wish you can let a comment. Thank you very much