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Coolant leak

213 Views 5 Replies 6 Participants Last post by  kenny2sienna
Hi Guys,
As I pulled into work this morning and parked, I noticed smoke coming out of the underside and engine bay and check engine light came on. It must have happened right as I pulled in. I checked and noticed a bunch of coolant on the underside. I didn't have time to do any further inspecting. I should be able to pull the code around lunch time. In the meantime, any initial ideas on what the issue may be?
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Obviously it’s hard to visualize w/o being there but

I would look at your coolant hoses first. They do deteriorate overtime and either burst due to fatigue and/or one of your clamps let go.

There are also various fittings that needs to be examined.

Check the coolant cap.
If it’s worn then it will not hold pressure and coolant will boil over and escape

Basically, follow all of the coolant hoses first. Start where it’s wet and narrow it down.

Either fill it w/distilled water and flush it later or 50/50 coolant to refill then start the engine to pressurized the system and observe where it’s spewing out.

If it’s a burst hose, depending on where and how severe - you may be able to use self sealing vulcanized tape to get you limping by to get home until you can do a proper fix.

(╭☞ ಠ ͜つ ಠ )╭☞ r=1+sinθ
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Could also be the heater tee's, they are under the intake hose by the throttle body.
I would hesitate to drive it anywhere until you figure this out. There have been several on here that cooked an engine when a coolant leak happened and it overheated.
If it’s a 3MZ van, check the plastic pipe that goes between the lower radiator hose and thermostat.

‘04 LE FWD 211K miles
As Oppa mentioned it, check the all hoses first and then check the thermostat housing (black plastic connected with lower coolant hose) because some owners had cracked the plastic housing.
I recently replaced the lower coolant hose because there was small leaking between the housing and the lower hose. Fortunately, the thermostat housing of my Sienna has no problem. It is pretty hard to replace the thermostat housing.
Good luck!
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