Coolant leak troubleshooting

[ccasteel]

My heater hose T's broke the other day at 147k. After replacing the T's, hoses and refilling the radiator all was well for a few days. Then I started to see small amounts of steam coming from under the hood towards the front right(passenger) side. By the time I get the hood open I can't tell where it's coming from. If I leave it running with the hood open the fan blows it all around, again making it hard to tell from where the leak originates.

My trips have all been short commutes to work and back. Barely gets warmed up before I'm stopping. So this weekend I took a longer drive in an effort to see if I could make it a little more evident. The steam showed up briefly while at a light, but by the time I got to a parking lot it had stopped. The overflow tank is right at the full mark, so I figured maybe I just overfilled the radiator.

Unfortunately tonight it started up again. It's pretty cold here so I let the car warm up a few minutes before heading home from work. By the time I got to my driveway, it was steaming pretty good. Temperature gauge reads normal, heater works fine and overflow is still at full. I just can't tell from where it's coming.

Any suggestions on where to start troubleshooting? It's my DD, so I can't be without it for long.

 

[nissanh]

The coolant will leak and gauges and all will be fine until all the coolant is gone. So you have to locate the leak soon.

You will have to remove the engine cover and then the air intake line to have a closer look.

 

[2001LC]

Hopefully you're using Toyota Red coolant, as it will leave red dry crusty flakes at leak.

1) Since it stop when you park, I suspect it's blowing back from Radiator as you drive.
Look at:
Radiator cap.
Front of radiator, under radiator upper support (Leak at plastic top to core weld).
Upper & lower radiator hoses.
Drain cock.

2) Since you replaced Tee's:
Inspect Tee's.
Also all six hoses paying special attention to hose and mounts on rear engine cross over.

3) Around thermostat & throttle body.

4) Weep holes (front and Rear under engine)

Check coolant level each morning when engine cold. Watch to see if dropping! Keep in mind the lower the ambient air temp the lower the level.

Note: Use a very good flash light during inspection.