Irritating Problem When A/c On + Fuel Consumption

[mjfuture]

Hi there,

Whenever I turn on the A/C the rpm rise as the compressor start which is normal... but somehow it delivers the power to the wheels also

in short: compressor click = race pedal automatically activated

I hardly feel it when I pass 65 kph (40 mph) but under that it's really annoying.... especially here in Bahrain where is the longest drive without braking never exceed 15 minutes which is very rare

I one let it go from 0 kph with the a/c on... once the compressor clicked I released the brake and it's almost reached 30 kph (18 mph)

I'll try to upload a video ASAP

any suggestion would be appreciated

THX

[mjfuture]

opps forgot the fuel economy

I used to get about 14 - 16 L/100KM (16 - 14 mpg) estimated

but now 20 - 25 L/100KM (11 - 9 mpg)

PLZ HELP!!!

it's 95 ls400

[sha4000]

Is your check engine light on? that's terrible gas mileage if I understand you correctly.

[mjfuture]

no

no warning lights!!

the a/c and mileage issue are separated

a/c thing been like forever but the mileage less than a year

I read this before http://www.clublexus.com/forums/ls400/377171-diy-coolant-temperature-sensor-change-pics.html

I'm going to replace it but i need to know if anything else could be the effect

[landar]

Generally speaking, poor gas mileage means a rich mixture of fuel/air. And usually due to a "cool" running engine or a computer that 'thinks' the engine is running cool. A bad coolant temp sensor could be telling the computer to increase the fuel mixture all of the time. Or, perhaps, your engine really is running too cool such as a bad (stuck open) thermostat could cause. I suppose bad O2 sensors could also wreak havoc on your fuel trim.

[Chicken]

same issue here when it comes to MPG.

A full tank of gas only lasts me 250miles in the city and around 300-325 on the highway. Doesn't matter if I use high octane ( 91 ) or premium ( 89 ).

[sha4000]

same issue here when it comes to MPG.

A full tank of gas only lasts me 250miles in the city and around 300-325 on the highway. Doesn't matter if I use high octane ( 91 ) or premium ( 89 ).

Do you have any check engine codes? You should be getting upward of 400 miles on a tank if the car is running properly. What year do you have, miles on it and when was the last time you had a tuneup?

[Chicken]

same issue here when it comes to MPG.

A full tank of gas only lasts me 250miles in the city and around 300-325 on the highway. Doesn't matter if I use high octane ( 91 ) or premium ( 89 ).

Do you have any check engine codes? You should be getting upward of 400 miles on a tank if the car is running properly. What year do you have, miles on it and when was the last time you had a tuneup?

No Check engine light. Got 126k Miles on it, oil changed ( regular, not synthetic) every 3000 miles or so. I've considered selling it , but it's only been less than a year since I bought this car.

[sha4000]

Do you mean your car will accelerate on it's own or that the rpms just go higher while in park?Sign up on the other lexus forum and post your problem. You might get more suggestions over there.

http://www.clublexus.com/forums/ls400-183/

[mjfuture]

Hi guys

Do you mean your car will accelerate on it's own or that the rpms just go higher while in park?Sign up on the other lexus forum and post your problem. You might get more suggestions over there.

http://www.clublexus.com/forums/ls400-183/

yes the car will accelerate on it's own whenever i turn on the ac

done that already
http://www.clublexus.com/forums/ls400/743825-a-c-fuel-consumption-ls400-95-a.html

but i'll try to keep both posts updated

[mjfuture]

I replaced the coolant temperature sensor two days ago.... but haven't notice any changes yet

next i'll change the gear oil

btw lander...

there is no O2 sensor on gcc models