Problems with Renault Kadjar 2021: difficulty accelerating, increased fuel consumption and possible defect in the charge air temperature sensor

Hi, it sounds like we have a similar problem. I own a 2019 Renault Megane, also a diesel. I have a bit of automotive experience, but I'm not a professional. My car had the same symptoms as yours. The workshop then issued the error message "Evaluation electronics defective (engine control unit)". That cost me around 1000 euros to fix. Not exactly a bargain, but since then the problem has been solved. It could be that your Kadjar has a similar problem, but I can't be sure without more information about the vehicle. Could you give me more details about your Renault Kadjar, such as mileage, service history and whether you have replaced any parts recently? This could help me give you better help. Good luck!

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Thank you for your quick reply. My Kadjar now has 112079 km on the clock and the last service was carried out on time. But apart from regular maintenance and replacing the usual wear parts, I haven't done any major repairs or parts replacements. This problem came as quite a surprise, so I'm at a bit of a loss. Hope this helps you to think about my problem. Thanks again for your help!

(Translated from German)

Hi, no problem, we'll try to solve the problem together. From what you've told me, it occurs to me that your charge air temperature sensor may be faulty, as you suspected. With a mileage of more than 100,000km, it definitely could be. The sensor can be damaged by things like oil contamination, water or rust. When I had similar symptoms on my Megane - the black smoke and hissing when accelerating - it wasn't ultimately a sensor malfunction, but the engine control unit. However, the main symptoms in my case were the engine warning light coming on and the loss of power. As you are also experiencing other symptoms such as high fuel consumption and whistling, it could also be the turbocharger exhaust valve. In my Megane, the error codes were then read out, which also makes sense for you. Several faults can occur at the same time, all of which need to be rectified. You should definitely go to a workshop and have the fault memory read out. This will give you and us clearer information. Nevertheless, I would recommend that you have the sensor and the turbocharger exhaust valve checked. Let me know as soon as you have more information! Good luck!

(Translated from German)

Thanks for the great tips. I will follow your advice and have the things you mentioned checked. Reading the fault codes definitely sounds like a good idea to get more accurate information. And interestingly enough, I never thought about the turbocharger exhaust valve before, but now that you mention it, that seems like it could also be a possible source of the problem. I hope to find a solution for my car soon. I will definitely message you as soon as I get back from the mechanic and have news. Thanks again for your support and tips! Take care and see you soon!

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