I changed the throttle body out to fix a rough idle and s...

Hello, my name is \*\*\*\*\* \*\*\*\*\* I will be helping you with your question today. I've been working on VWs for over 30 years now, so I should be able to help you through this. Please understand that some of my suggestions may require special diagnostic tools and equipment that many home mechanics may not have, but are often required. So, my first question is whether you're planning on performing your own repairs, or are you wanting to be armed with information before bringing it into your mechanic? **Also, the site automatically prompts for a phone call. It's very rare that I'm available by phone, so let's hold off on that for now. If needed after we exchange some information, I will do my best to take the time for the call.** Few other questions: 1) what scan tool are you using to diagnose? 2) what are the exact fault codes you're seeing? 3) why was the throttle body replaced? 4) how many miles are on your Tiguan?

1.I used my friends obd scanner he got from amazon. Its a cheap one. 2. Im seeing codes, p0101, p2293, p2187, p2177, p0300, p0303, p0301 3. I was driving a couple days ago and noticed the car was hesitating while trying to accelerate. I thought the throttle body needed to be cleaned so i cleaned it, that didnt fix it, so i replaced it and its misfiring now. 4. 124000

Ok, few minutes while I put some thoughts together. One other quick question: are you seeing any oil leaks near the union of the engine and transmission? (bellhousing)

No i am not

Ok, so these are all VERY common faults with the VW/Audi 2.0T TSI/TFSI engines, and they're related to the fuel mixture being too lean (too much air in the air fuel ratio). Typically the first part to fail that causes this is the crankcase breather bolted to the top of the valve cover. When the diaphragm inside the breather fails, then it causes excess vacuum on the crankcase, which acts as a vacuum leak. If left unchecked for too long, this excess vacuum then starts to suck the rear crankshaft seal inward, damaging it, which will cause an oil leak, and also allow excess air to be pulled into the intake from the bellhousing. The way we test all of this is with a vacuum gauge hooked to an oil cap fitting to check crankcase vacuum. If it's too high, then replace the crankcase breather/oil separator/pcv valve(all terms for the same part). If the issue continues, then the transmission will have to be removed and rear main seal replaced. Please let me know if I can offer any further information.