Lexus LFA Fuel Pump Issue

Hey! Sorry to hear you're having trouble with your LFA. Sounds frustrating! I had a similar issue with my old BMW 3 series, but it was a diesel. The symptoms were almost identical – check engine light, rough idling, and a noticeable power loss, especially when accelerating. In my case, it turned out to be the high-pressure fuel pump failing. Have you checked the fuel pressure? A faulty high-pressure pump can cause the fuel volume regulator to malfunction because it's not getting the correct fuel supply. You know, the fuel volume regulator's job is to maintain the correct amount of fuel being delivered to the engine, so if the pressure is off, it throws everything out of whack. I'm no expert, but it might be worth investigating!

Thanks for the quick reply! Regarding checking the fuel pressure, what's the best way to do that? Are there specific tools or procedures you'd recommend? Also, would a bad high-pressure fuel pump always cause the fuel volume regulator to fail, or could the regulator fail on its own?

Okay, so I'm not a mechanic but I did watch them fix my car. Basically, they hooked up a gauge to the fuel rail to measure the pressure. I think you can buy the gauge yourself, but you need to know what you're doing or you could make things worse. About the regulator failing on its own... it's possible, sure, but if the pump isn't working right, it puts extra stress on the regulator. Honestly, given the symptoms and the potential costs involved with an LFA, I'd strongly suggest taking it to a trusted mechanic. Let them run a proper diagnostic. It'll save you time, money, and potential headaches in the long run.

Thanks for the advice! I took it to a mechanic, and they confirmed it's a defective high-pressure fuel pump causing the fuel volume regulator issue. The repair, including parts and labor, is estimated at 1510€. Thanks again for your help!