Strange engine noise on cold start

[sugizo_esp]

Hi all,

I'm experience some noise recently after my 20k service.

On a cold start, i can hear some pumping and liquid injecting noise coming from the engine and it goes away pretty much when the rev drops down which is about couple of seconds.

Does anyone have similar experience?

I called in service depart and they said its driving belt problem and it shouldn't harm.

Should i take it back in asap?

[ninjaking777]

So the service department wont get rid of the sound for you? that is poor form.

You should tell them that it doesnt matter if it harms the engine or not, the sound wasnt there before they touched it so they should get rid of it

If "swooshing" is a good way to describe the sound you are hearing..

i have had that problem before too...actually i still have it.. but i brought it back to mechanic so many times to get rid of the sound i cant be stuffed anymore.

But if it is the same as what I had,

its because they drained/changed the coolant and didnt completely clear out the air pockets running in the pipes of the cooling system.

hence when engine first turns it will make the swooshing sound.

But apparently harmless as there is still sufficient coolant...its just the air pockets.

[sugizo_esp]

So the service department wont get rid of the sound for you? that is poor form.

You should tell them that it doesnt matter if it harms the engine or not, the sound wasnt there before they touched it so they should get rid of it

If "swooshing" is a good way to describe the sound you are hearing..

i have had that problem before too...actually i still have it.. but i brought it back to mechanic so many times to get rid of the sound i cant be stuffed anymore.

But if it is the same as what I had,

its because they drained/changed the coolant and didnt completely clear out the air pockets running in the pipes of the cooling system.

hence when engine first turns it will make the swooshing sound.

But apparently harmless as there is still sufficient coolant...its just the air pockets.

Not sure if it's the same sound until we hear it on the spot.

But it does sounds like some liquid spraying or liquid pumping noise and gradually fades out on engine warm up

[pinzvidz]

Not sure if it's the same sound until we hear it on the spot.

But it does sounds like some liquid spraying or liquid pumping noise and gradually fades out on engine warm up

Is your A/C switched on at the time of engine start-up? There's 2 scenarios here; 1: I've seen plenty of cases where the belt isn't tensioned properly and it makes a rather short loud squeal sound on start-up (sometimes drawn out). Toyota cost-cutting is the problem here as the belt tension is done via the old manual method instead of an automatic tensioner (why Toyota?!?!?). 2: The A/C system is either undergassed or overgassed, which I suspect is your issue. This will definitely cause some strange noises such as the ones you describe. A/C for Ascent/Conquest/Levin SX is dealer fitted, and PD fitters are generally not mechanics, so they never do the job properly. I'd ask for the pressures to be checked, and check your belt tension as well.

[sugizo_esp]

Not sure if it's the same sound until we hear it on the spot.

But it does sounds like some liquid spraying or liquid pumping noise and gradually fades out on engine warm up

Is your A/C switched on at the time of engine start-up? There's 2 scenarios here; 1: I've seen plenty of cases where the belt isn't tensioned properly and it makes a rather short loud squeal sound on start-up (sometimes drawn out). Toyota cost-cutting is the problem here as the belt tension is done via the old manual method instead of an automatic tensioner (why Toyota?!?!?). 2: The A/C system is either undergassed or overgassed, which I suspect is your issue. This will definitely cause some strange noises such as the ones you describe. A/C for Ascent/Conquest/Levin SX is dealer fitted, and PD fitters are generally not mechanics, so they never do the job properly. I'd ask for the pressures to be checked, and check your belt tension as well.

Definitely not the A/C. I always switch off everything. The mechanics i talk to on the phone thinks the driving belt wasnt adjusted properly. I'll probably take it in sometimes this week. Such a waste of time.