I just purchased a 2003 Lexus GX 470 with 195,000 miles on it. On start up when the engine is cold, there is a noise coming from the right side of the dash that sounds like a pump for about 20 seconds and then stops. It appears to only make this noise when the engine is cold. I thought it was the compressor for the airbags but found out that that is located at the rear of the vehicle. Thanks for any help.
Pump noise on start up (1 Viewer)
- Thread starter Bamalx
- Start date
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Brake booster most likely. Check the fluid. Is your brake soft?
mine does it too. If you turn the key on, you get a whirring sound for about 5-10 seconds. Once you start the truck the secondary air pump will run for about 30 seconds then shut off, it's noticeable once it shuts off.
I don't think the '03's got the secondary air injection.
It doesn't. It's the booster priming
Ah true! My bad
That is your climate control. Mixer moves around. May be trash in your blower too
After having a repair done to the secondary air injection system, I now notice a fan running at high speed on a cold start up. It runs about 30 seconds, then sounds like it shuts off, but gets quiet enough I can't hear it. My understanding is this fan is helping to blow air to warm up the cats? Or something like that. Odd that I didn't hear it before the repair, but now I do...
How loud does this climate mixer noise get?m I'm getting a very loud pump sound from the glovebox. It almost sounds like the air shock compressor is suddenly inside the car. I doubt it's the brake booster unless that sudden loudness is a sign of impending failure, I'm used to the brake booster and the shock air compressor sounds, as well as the normal servo gremlin clicks and burrrs and whirs from the blend doors. The sound occurs when the electronics are powered on at first, without even turning the engine over and they continue and stop abruptly or sometimes fade out.
Glovebox is the blower motor. Likely have garbage getting passed the cabin filter. Drop the glovebox and you can see the little filter door for the blower. Check that and if you need too the blower is right under it and held in with 3 bolts IIRC and is easy to drop and clean inside the fan housing. If it is a bearing noise that whole blower assembly is relatively cheap and easy to source and replace.
Did you ever figure out what this was? I've got the same thing going on with a newly acquired 2007 GX470 with 175,000 miles.
I replaced the blower motor and cabin air filter but that wasn't the fix. I changed the vent selection one time on this car and then barely any air would blow out so I do think there is a problem with the blend door motor(s) but based on what I've read, the noise that we are hearing (like a compressor) wouldn't be the same noise that people get from those going bad.
I replaced the blower motor and cabin air filter but that wasn't the fix. I changed the vent selection one time on this car and then barely any air would blow out so I do think there is a problem with the blend door motor(s) but based on what I've read, the noise that we are hearing (like a compressor) wouldn't be the same noise that people get from those going bad.
