BMW X5 Cold Start and Rough Idle Issues Solved

Hey there! I had pretty similar issues with my 2007 BMW X3 3.0i last winter. The symptoms you're describing match exactly what I experienced, rough cold starts, long warm-up times, and increased fuel consumption. Took it to my mechanic and turns out it was indeed the electric auxiliary heater that was faulty. The PTC heating element had completely failed, causing the engine management system to compensate by enriching the fuel mixture during warm-up. This was triggering the check engine light too. The repair wasn't particularly complex, but it was crucial to fix as it was affecting the engine's overall performance and efficiency. The mechanic also found some related electrical connections that needed cleaning and resealing while doing the work. My advice? Get it checked soon. These symptoms won't resolve themselves, and continuing to drive with a faulty auxiliary heater can lead to other issues. Based on my experience, you're likely dealing with the same problem I had.

Thanks for sharing your experience! That really sounds like what I'm dealing with right now. Mind if I ask how much you ended up paying for the repairs? Have you had any other issues pop up since getting it fixed? Just want to get an idea of what I'm in for cost-wise and if I should expect any other related problems down the line with my X5.

Hey again! Just wanted to follow up about the repairs, I got my X3 fixed a while back and I'm happy to report it's running like a charm now. The total bill came to 350 € for replacing the faulty electric auxiliary heater, and honestly, it was worth every penny. Since getting it sorted, my car starts up smoothly even on cold mornings, warms up way quicker than before, and my fuel consumption is back to normal. Haven't had a single related issue pop up since the repair, which was about 8 months ago now. The check engine light hasn't made an appearance either, so that's a relief! I know you mentioned being hesitant about mechanics due to a past experience, but this really isn't something you want to put off. The longer you wait, the more fuel you'll waste, and there's always the risk of related problems developing. My mechanic explained that when the PTC heater isn't working properly, it puts extra stress on other engine components. Just make sure you find a reputable BMW specialist who knows what they're doing with these auxiliary heaters. Hope this helps with your decision!

Thanks so much for all the detailed info! I finally got the courage to take my X5 to a mechanic yesterday. You were right, it was the auxiliary heater causing all the trouble. Funny enough, my repair bill was pretty close to what you paid, around 375 € total. The mechanic was actually really great, totally different from my last experience. He showed me the old heater and explained everything clearly. Got it all fixed in about three hours, and wow, what a difference! Started up the car this morning and it purred like a kitten. No more sluggish starts or excessive fuel consumption. Really appreciate you sharing your experience, it gave me the push I needed to get this sorted before it turned into something bigger. Feels good to have a properly running car again. Thanks for helping me avoid a potentially bigger headache down the road!