EGR Valve Symptoms: Black Smoke and Power Loss Guide

Had the exact same symptoms on my 2015 Chevy Cruze diesel last winter. The rough idle, black smoke, and power loss were identical to what you're describing. The check engine light triggered due to excessive soot buildup in the EGR valve. Turned out the valve was completely stuck open, causing poor combustion and affecting the vehicle emissions system. The mechanic found the EGR passages were totally clogged, which was forcing the engine to run rich. This explained the terrible fuel economy and black smoke. It's definitely a serious issue that needs addressing soon, if left unchecked it can damage your catalytic converter and cause more expensive problems down the line. In my case, they had to clean the entire EGR system and replace the valve. The fix resolved all symptoms immediately, engine ran smooth again, power returned to normal, and fuel consumption went back to usual levels. Would recommend getting it checked soon, these symptoms won't improve on their own and could lead to failing your next emissions test if not fixed properly.

Thanks for sharing your experience! Had my Cruze fixed about a month ago for these recirculation issues. Your symptoms match exactly what was happening with mine, especially that nasty black smoke and power loss during acceleration. Quick question, do you remember what you paid for the full EGR valve repair? Mine was pretty pricey and I'm curious how it compares. Also, has everything been running smoothly since the fix? No check engine lights or other automotive repair issues popping up? The emissions test concerns you mentioned are spot on, I was worried about that too. The EGR cleaning and replacement definitely solved my immediate problems, but always good to hear about long-term results from others who've dealt with it.

Had the EGR valve fixed at a local shop for 355. Absolutely worth every penny, fixed the rough idle and power issues completely. The check engine light hasn't come back since, and the engine runs like new. No more black smoke or weird noises during acceleration. The mechanic showed me the old valve, totally gunked up with carbon deposits that were messing with the exhaust gas recirculation. Since getting it sorted, fuel economy is back to normal and the catalytic converter's working properly too. It's been about 6 months now with zero issues. Just make sure to use good quality fuel and do regular oil changes, helps prevent that carbon buildup from happening again. Glad you got yours fixed too. These EGR problems are pretty common on our cars, but once properly repaired, they typically stay fixed.

Thanks everyone for the solid advice. Quick update on my situation, took the car to a new mechanic last week and the diagnosis was spot on. Had a serious vacuum leak around the EGR valve, which explained all those symptoms. Final bill came to 380 for the complete job, cleaning the whole system and replacing the valve. Sure, it wasn't cheap, but seeing the gunk they cleaned out made it worth every penny. The mechanic was great, showed me all the carbon buildup they removed and explained how it was affecting everything. Car's running like new now. No more check engine light, black smoke's gone, and power's back to normal. Fuel consumption dropped back down too. Best part is passing the shop's emissions test with flying colors after the fix. For anyone facing similar issues, don't wait around hoping it'll fix itself. These diesel engines need proper maintenance, and catching problems early saves money in the long run. Really glad I didn't put this repair off any longer.