Audi Q3 Power Loss Points to Throttle Body Issues

Having some experience with VAG cars, I encountered a very similar issue with my 2012 Audi A3 2.0 TFSI. The symptoms you describe match exactly what I experienced, reduced power, rough idling, and sluggish response delay when pressing the accelerator. Initially thought it was the throttle body, but after diagnosis it turned out to be the accelerator pedal module that was failing. The car would occasionally go into limp mode, especially during cold starts. This component affects fuel efficiency and overall engine performance quite significantly. The repair involved replacing the complete pedal module assembly, which cost 265 Euro including labor. After replacement, the throttle response and engine performance returned to normal. Before jumping to conclusions, could you share: Does the issue occur more frequently during cold starts? Have you scanned for error codes? What engine variant does your Q3 have? Does the check engine light flash or stay constant? With this information, we can better determine if your issue matches what I experienced or if it might be something else.

Thanks for the feedback. Just had my last service at 28691 KM. My check engine light stays constant, never flashes. The issue happens pretty much all the time now, not just during cold starts. The car shows a P2135 error code when scanned. Given the symptoms and code, the throttle body issues make sense but wanted to rule out the pedal module you mentioned. My fuel efficiency has also dropped noticeably in the past weeks. Im running the 2.0L TFSI engine. Would you recommend getting the throttle body cleaned first before considering a full replacement?

Based on the P2135 code and constant symptoms youre describing, this seems more likely to be a throttle body issue rather than the pedal module situation I had. The error code specifically points to a throttle position sensor problem, which is built into the throttle body assembly. While cleaning might help in some cases, given your symptoms and the specific error code, I dont recommend just cleaning as a fix. When I initially tried cleaning my throttle body on my previous A3, it only provided temporary relief before the issues returned. The constant reduced power state and steady check engine light, combined with your fuel efficiency drop, strongly suggest the throttle sensor has failed. Unlike my pedal module situation which was more intermittent, your symptoms match classic throttle body failure. Replacement cost typically runs between 350-450 Euro for these engines, including labor. Make sure to get a genuine part, as aftermarket throttle bodies can cause response delay issues and may not integrate properly with the engine management system. For reference, what did the service center say about the error code during your last visit? If they didnt mention it, the issue might have developed after the service.

Thanks for the detailed response. You make a good point about the cleaning likely being just a temporary fix. The service center didnt mention any error codes during my last visit, so this definitely developed after. The symptoms started about 2 weeks after the service. Given what youve shared about the throttle sensor issues and the constant symptoms Im experiencing, I think going straight for the replacement makes more sense than trying intermediate solutions. The fuel efficiency drop is really starting to hit my wallet too. Im going to book it in for the throttle body replacement since the P2135 code and all symptoms point directly to that. Good to know about the genuine parts recommendation, will make sure to specify that. The 350-450 Euro range for the repair sounds reasonable considering the alternative of staying in this reduced power state. Going to get this sorted next week. Rather get it fixed properly now than risk getting stuck in limp mode on the highway.