bigwave

Hello everyone

We have been happy with our 2006 RX400h since we purchased it about 6 months ago. However, I've noticed something this summer that has me quite concerned. When the car is running at idle for any length of time (stopped for a period of time in traffic for example) the air conditioner stops blowing cold air. Once you start driving it slowly begins to blow cold air again.In the hot Atlanta weather (and with our terrible traffic) this is unacceptable. Is there a problem with the car? I can't imagine this would be "normal" in an expensive luxury vehicle like the Lexus RX400h.

My second question is what MPG should I reasonably expect to get? We bought the car thinking that it's forte would be in getting stellar mileage in our ever present stop and go Atlanta traffic (most of our driving). So far about the best we've seen, according to the vehicle's computer calculations) is about 24-25 MPG. Thoughts?

Bigwave

herbvdh

On the A/C question I have noticed that on occasion that the air tends to get a little humid then when you start up again it gets cold. (At your next service you could have Lexus check it out)
On your gas milage I would say that is normal as with the heat it does go down a little as with the bitter cold we get. Also a lot of extreme short trips ie: 5 to 10 minutes gas milage will suffer as nothing gets fully warmed up.
I did a full study of MPG versus Temperature graph which is up here on Club Lexus somewhere. Here is a link to my gas milage you could see the differences.
http://www.greenhybrid.com/compare/m.../car/5831.html

Tony

Your AC does not sound like its working right. The RX400H runs the compressor on battery power so it should be cold all the time regardless of what the engine is doing. I live in Las Vegas and even at 115-120 degrees in stop and go traffic where the engine never kicks on except to recharge the batteries the AC is to cold. Gas mileage will go down with higher temps because the combustion engine is more efficient with cooler air which is more dense than hot air. Driving styles on the gas pedal can effect that. My MPG in summer with AC and stop in go traffice is 25mpg combined 27mpg but I coast alot. Out of all the cars I have owned the RX has the coldest AC unit I have ever had.

kenne74

I had the same AC issue with my wife's 06 400h. Apparently there is a recall that was never sent out to the owners. If i'm not mistaken they ended up replacing 2 hoses on the ac and the problem was solved. If you need more info i can contact the dealer to get the specifics.

As for the mileage it all depends on how you drive the temp and a hundred other variables. The heat effects the batteries, so your engine probably kicks on more in the summer than usual. Just drive it like you stole it and enjoy it. Remember if your getting above 20mpg then your still doing better then the rest of the world with there gas guzzing SUV's. I think we get around 23mpg and my wife doesn't drive it like a hybrid should be driven.

riwyle

I checked a couple of on-line sites and could find no mention of a TSB or recall on RX400 A/c systems. Could you find a TSB reference number?

SLegacy99

Your A/C def. should still produce cold air when then engine stops.

On our most recent road trip, doing 70 MPH I was able to achieve 27.5 MPG with the A/C. In traffic though, mileage goes up (which is great) but then back down to recharge the battery because the A/C is definately a drainer.

Sewell

iTrader: (9)

This is strange. I experienced the exact same thing in rush hour traffic in Dallas just last week. It didn't dawn on me until it was my turn to get onto the on ramp and I was then blasted by cold air. I believe it was 107-108 that day with high humidity. The 400h was already hot and I was already perspiring so I didn't notice the A/C concern until it really started blowing cold. I'll look into this tomorrow. I know there is no campaign (recall), but I remember something of a TSB concerning the A/C.

As for gas mileage and performance...drive it like you stole it. I drove from an hour west of Denver to Dalls in just 11.5 hours and acheived a surprising 21 mpg. You do the math.

The highest I can recall acheiving on a trip lasting more than an hour or so is just under 30 mpg.

kenne74

Sorry i didn't get back sooner was out of town. I contacted the dealer and yes it was a TSB not a recall. Here is the info from the repair.

TSB - AC002-05
Replaced - AC Clutch and AC hose/line

Hope this helps. Made a world of a difference after the work was performed and it gets crazy hot in Az.

filmteknik

That's interesting. There's an AC clutch on the hybrid? I thought they had an electric compressor.