coachstu

I have a 2003 GX470. I just began experiencing an odd noise from the dash. Sounds like it's coming from the instrument panel or behind stereo. It happens whether the car is started or not and even when the car has sat overnight. If I turn ignition to on, without starting the engine, the noise is there. Sounds like paper crunching or water gurgling. It's there regardless of whether the AC or heat is on. Any idea what this is?

coachstu

UPDATE: For anyone having this issue, this is my fix. I think. I had done searches on the forum that talked about burping the coolant system but didn't think this was my issue as the problem existed even when engine was off. Contrary to what I posted above, my heater was no longer working. I did take car to jiffylube to flush coolant system. I don't actually think they did a full flush. However, on the drive back I did notice my heat was working again but the noise was still there. I let the truck cool down and checked radiator fluid. It was low. So I added coolant directly to the radiator, ran the car for about 10 minutes with hear on full blast. Noise is now gone. Must have been air and jiffylube didn't bother burping it. Or, it was low on coolant and jiffylube didn't fix that either. In any event, definitely coolant related. My coolant was brown so I'm hoping I don't have another issue going on or that someone didn't pour stop leak in the radiator.

chiph9

Make sure the coolant they used is compatible with your engine & radiator.
Brown doesn't sound good - likely still the factory fill. Coolant should be changed about every 3 years.

Chip H.

coachstu

SECOND U[PDATE: It is not the coolant or air. Burping only worked because I turned on the heat full blast. The noise came back when I used AC. Confident it's a servo motor. I can make noise go away if I blast heat, but it will come back. Almost like the heat unsticks the gears in the servo motor.

How hard is it to replace servo motor?

coachstu

Coolant looks OK. it's brownish because the pink coolant I added when I got the truck is mixing with whatever color was in there. I can't do a full flush. Do you suppose draining the radiator 4 times and topping off with the correct coolant will get most of the old coolant out of there?

chiph9

Probably just doing a 2x drain + fill over 100 miles will be enough.

Chip H.

ALAN553

if you let jiffy lube do the oil to...i'd check that also...the name "jiffy" when working on my car? take to Careful Lube next time...lol

coachstu

I hear ya. Honestly, if I'd known they were not going to actually flush the coolant I would never had done it. A drain and refill takes me 10 minutes. I was in a hurry to leave town and figured there was air in the coolant system and it would fix it.