About six months ago I purchased my first Lexus, a 2007 ES350 with 42,000 miles (it now has around 45,000 and was just given it's first oil change about 500 miles ago). It has started exhibiting the engine chatter that I have seen mentioned all over the Internet as something Lexus calls "normal" - although I disagree, this sort of noise from a luxury vehicle is not normal at all IMO, but reading of others experiences trying to get this corrected, I figured I would live with it and just let the car warm up for five minutes before driving, this seems to lessen the chatter which disappears after about 10 minutes of operation at steady speed.

Sadly, the past couple of days it has experienced exhaust backfire the first time I brake on a highway after about 5 minutes of engine operation at 50-60MPH; it sounds like a motorcycle, a poppity-poppity-poppity-pop-bang-bang. The second braking will result in a couple muffled pops, then it pretty much evens out. It seems to correlate with engine temperature, possibly manifold temperature.

There is no loss of power, the engine still accelerates normally according to how much throttle is applied, but the noise, which worsens with cold (the backfiring coincides with the arrival of 10-20 degree weather) is embarrassing and in my opinion, should also be an embarrassment to Lexus as this noise is noticeable to other drivers.

I have not yet contacted the dealer, I wanted to get the opinion of other drivers who may have had similar issues first, their experiences with the dealership or third party mechanics. This is a Lexus certified vehicle, six months into the three year warranty. In my opinion ANY backfiring is indicative of engine malfunction and problem determination should be covered under the warranty.

Any input is greatly appreciated. Thank you.

 

If your engine is backfiring it should light up the "check engine" light and have some codes that your dealer can check. And that is what you need to have done right away - take it to your dealer before the backfiring damages the catalytic convertors or something else. It is not "normal" and can probably be diagnosed and repaired pretty quickly.

Dave Mac

 

I agree with Dave Mac. Should be checked out ASAP.

Probably not much can be done about the engine noise, but the backfiring isn't good and can most likely be corrected.