You are going to have to back probe to verify whether the issue is wiring or throttle body. I have never seen an issue with wiring, but problems vary per geographic location.
I have only replaced one throttle body, and it was because the shaft for the butterfly had begun to allow condensation and oil past and into the throttle body electronics. Upon opening the throttle body I found about 2 oz of oil, and broken teeth on the potentiometer gear.
Replacement takes us about an hour, if you have the proper tools on hand it may take you 2-3 based on skill level.
A Bentley Manual is going to be your best investment, next to oil changes every 5,000 miles.
I highly recommend AGAINST trying to open the throttle body, there is small Torx screws and a heat applied glue that holds it together. The chances of you breaking the body are very high, and with what you are saying a new throttle body will be the "part" to fix it.
Finally i took it to a tech, he removed it and found out that the valve would not open/close when pressed manually with his bare hands! It was the mechanism that was faulty, that's why the valve would not turn when pressed. 2 out of10 times when pressed it would turn, the rest, it would stay stiff!
Replaced it and so far so good.
One question though, is your throttle body plastic or metal and does its say VDO on it?
So i guess now my two main issues are
1. how do i replace the throttle body, which i have no clue in how to do so! Is this described in the Bentley manual?
2. which part no. is the throttle body described in real oem?
MINI P/N is: 13-54-8-624-189. Don't try to open up your existing TB to fix it. It is a sealed unit, the only reason I was able to open one is because I was able to diagnose that it was the fault and had replaced it with a new unit.
Feel free to give us a call and we can get you one on the way: 586-792-6464
