Low coolant and poor air-conditioning at idle
 

Wow, it's been 14 years since I last posted here. Good vehicle!

2000 SR5 with 176k miles. Radiator & water pump/timing belt replaced 2 years ago.

Noticed that the coolant reservoir was needing juice every few weeks, no visible leaks in the driveway. Recently, the AC started to noticeably struggle while at idle. Took it to a new mechanic (bad idea). They replaced lower radiator hose (claimed there was a leak at where it connected to the radiator). They leak checked the AC (none found) but recharged it anyway. Still having to add coolant and AC is still struggling.

I can smell coolant around the hood after vehicle is hot, there is no white smoke, sweet exhaust smell or visible leak. There is some wet guck on the block below the water pump.

If the water pump is bad, would that affect the AC system? I'm taking the rig back to the mechanic but don't really trust them at this point. Appreciate any guidance or feedback.

Mahalo!

Check the hose clamps on the back of the engine. I’ve had a few coolant leaks back there over the years.

Replace your clutch for your cooling fan for the AC issue.


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Thanks for the advice. Update:

I read in a 4th gen discussion to check the battery terminals. My negative was loose, replaced it. AC went from blowing 60' at idle to now 40'. Apparently, the condenser fan is magnetic and needs that solid current. Also noticed engine temp (using an infrared thermometer) went from 208' to 188'. Could that have been burning the coolant too?

Mostly coolant disappearing would be a leak or head gasket burning it. Do you have a rear heater? Are its lines good and not leaking?

There is only one fan and it’s driven by a drive belt off the crank pulley. Infrared thermometer is not an accurate way of measuring the engine coolant temp. Best way is looking at the ecm data.

The ac system and the engine cooling system are two different systems. The only overlap between the two systems is the fan and fan clutch. The fan cools the condenser and the radiator. The engine coolant and the ac system never meet at any point.

Your heater core coolant flow valve could also be not closed all the way causing your ac to be warm.

Brillo, this vehicle does have the rear heater (my son turns it on often so I recently removed the fuse...we live in Hawaii).

I have no idea where to begin looking for rear coolant lines.

The warm AC at idle appears to be fixed and was caused by the loose negative battery terminal.

Appreciate all the responses, I'm of a weekend oil changer type. Lol

Well you see fluid on the floor near your passenger front seat.

I doubt it's rust related. Might be a leak somewhere. :)

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No leaks in the cabin. Does this point to a headgasket leak? Is there an easy way to test that?

"There is some wet guck on the block below the water pump." points to a
possible water pump leak. When's the last time the timing belt was changed?
Maybe a two-fer if it's 90k miles or more.

Water pump and timing done less than 2 years ago, maybe 25k miles since.

Solved
 

Ended up taking the truck and issue to a family friend that is a Toyota dealer tech.

Coolant leak= bad intake manifold gasket

AC intermittent failure= stuck expansion valve & small evaporator refrigerant leak

The first shop was and are a complete joke, not even close!