Cadillac ELR Throttle Body Failure Causes Power Loss

Had a similar issue with my 2018 Cadillac CT6 Hybrid. As someone with moderate repair experience, I can share what worked in my case. The symptoms matched yours, reduced power, check engine light, and the car went into limp mode. After diagnostics, it turned out the accelerator pedal module was malfunctioning, causing inconsistent throttle sensor readings and restricted air intake. The total repair cost was 265€, which covered both parts and labor. The fix involved replacing the entire pedal module assembly. Initially thought it was the throttle body, but the diagnostic showed the actual culprit was the pedal electronics. Quick questions to better assist: Are you getting any specific error codes? Does the issue happen more frequently when the engine is cold or warm? Have you noticed any changes in fuel consumption? Does the throttle response feel different at varying speeds? These details would help determine if your issue matches what I experienced. While throttle body issues can show similar symptoms, its worth checking the pedal module first since its often overlooked and typically costs less to fix than a complete throttle body replacement.

Thanks for sharing your experience. My last service was 2000km ago, around 140000km. The error code is P2135, and the check engine light stays on constantly. The throttle response feels sluggish especially when the engine is idling, and fuel consumption has increased by about 15%. The issue seems worse when the engine is cold, often triggering limp mode during morning starts. The throttle sensor readings from my OBD scanner show inconsistent values, which has me leaning toward throttle body replacement. Plus theres a slight whistling sound from the throttle area thats most noticeable at low speeds. But your point about the pedal module is interesting, I hadnt considered that as a potential cause. Would you know if the pedal module issues typically show similar error codes?

Thanks for those additional details, it actually changes my initial assessment. The P2135 code combined with the whistling sound and cold-start issues strongly suggests this is indeed a throttle body problem rather than the pedal module I initially dealt with. The pedal module issues typically trigger different codes (usually P2100 series but not P2135). The throttle body directly impacts engine idling and fuel efficiency, which aligns with your 15% increase in fuel consumption. Based on your symptoms and my repair experience, a throttle body replacement is likely needed. The inconsistent air intake and sensor readings are classic signs. The repair costs typically run 400-600€ for parts and labor, significantly more than the pedal module fix I originally had. A few tips from my experience: Get the throttle body cleaned first if not already tried, Check the wiring harness connecting to the throttle body, Have the ECU recalibrated after replacement, Consider replacing the air filter while the system is opened The whistling sound you mentioned is particularly telling, never experienced that with my pedal module issue, but its common with failing throttle bodies affecting proper air intake regulation.

I appreciate the detailed follow-up. After hearing your experience and comparing symptoms, Im convinced were dealing with different issues. The whistling sound and P2135 code really set my case apart from your pedal module situation. Im going to move forward with the throttle body replacement since all signs point to that being the core problem. The impact on engine idling and overall fuel efficiency matches what others have described with faulty throttle bodies. Ill definitely follow your advice about checking the wiring harness and getting the ECU recalibrated post-replacement. The cost range you mentioned of 400-600€ helps set realistic expectations. While its more than your pedal module repair, it seems reasonable given the components involved. Ill make sure to replace the air filter while everything is opened up, makes sense to do preventive maintenance while accessing that area. Going to schedule the repair this week since the air flow issues and cold start problems are getting worse. Thanks for helping narrow down the diagnosis and sharing those repair tips.