Diagnosing an Overheating Issue as Blown Gasket, Air in Coolant System, or???
05-26-19, 04:40 PM
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Diagnosing an Overheating Issue as Blown Gasket, Air in Coolant System, or???
Howdy folks, thank you in advance for your time, hospitality and help that you're willing to offer.
As the title states, I'm trying to diagnose the overheating issue with my 2009 RX350 and would appreciate any insight you have. Here's the timeline of events:
Driving on the highway - the coolant line connected to the radiator cap came off and sprayed coolant everywhere. I noticed white smoke billowing from the hood. My VSC Off and Check Engine lights came on and my temperature gauge dropped to nothing (below Cold) - I pulled over.
After opening the hood, I used a zip tie to put the coolant hose back on the nozzle connected to the radiator cap, then filled up the overflow tank with coolant and waited a bit before turning the car back on.
Once I started it, the temp gauge began to fluctuate between normal, hot and cold. I pulled over when I could and wiped off the coolant from the battery terminals thinking that was the issue. I then reset the Check Engine and VSC lights. It solved the fluctuation issue, but after less than a minute of driving the temp gauge began to rise from normal to hot in a consistent manner.
I pulled over again and sat there for 30 minutes thinking the engine must've been extremely hot and it just needed time to cool down.
Began driving 30 mins later and within a minute the temp gauge rose to Hot again. This cycle of pulling over, resting, then driving for <1 minute until it reached Hot again persisted till I got home.
Once home, I popped the hood and could hear a gurgling/bubbling sound coming from behind the overflow tank on the passenger side of the engine.
My car is parked on a flatish surface and cooling down at my house now. I believe there is either air in the coolant lines or (hopefully not) a leaking/blown head gasket, or something else like a stuck thermostat. What are your thoughts?
I'm not exactly a car person, but I'm willing to tear most things a part and give it the DIY college try. Again, any help is appreciated. Thank you for your time.
As the title states, I'm trying to diagnose the overheating issue with my 2009 RX350 and would appreciate any insight you have. Here's the timeline of events:
Driving on the highway - the coolant line connected to the radiator cap came off and sprayed coolant everywhere. I noticed white smoke billowing from the hood. My VSC Off and Check Engine lights came on and my temperature gauge dropped to nothing (below Cold) - I pulled over.
After opening the hood, I used a zip tie to put the coolant hose back on the nozzle connected to the radiator cap, then filled up the overflow tank with coolant and waited a bit before turning the car back on.
Once I started it, the temp gauge began to fluctuate between normal, hot and cold. I pulled over when I could and wiped off the coolant from the battery terminals thinking that was the issue. I then reset the Check Engine and VSC lights. It solved the fluctuation issue, but after less than a minute of driving the temp gauge began to rise from normal to hot in a consistent manner.
I pulled over again and sat there for 30 minutes thinking the engine must've been extremely hot and it just needed time to cool down.
Began driving 30 mins later and within a minute the temp gauge rose to Hot again. This cycle of pulling over, resting, then driving for <1 minute until it reached Hot again persisted till I got home.
Once home, I popped the hood and could hear a gurgling/bubbling sound coming from behind the overflow tank on the passenger side of the engine.
My car is parked on a flatish surface and cooling down at my house now. I believe there is either air in the coolant lines or (hopefully not) a leaking/blown head gasket, or something else like a stuck thermostat. What are your thoughts?
I'm not exactly a car person, but I'm willing to tear most things a part and give it the DIY college try. Again, any help is appreciated. Thank you for your time.
05-26-19, 07:51 PM
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Just wanted to update everyone: after doing my own research and sifting through all the BS that's out there, I came across this thread (https://www.clublexus.com/forums/rx-...hermostat.html) with a response from Mesquite77, which led me to this thread (https://www.clublexus.com/forums/rx-...g-coolant.html) in which Mesquite77 offers up a procedure for bleeding the cooling system:
Without any help from anyone in determining where the "upper drain plug" was, I did some more research to find two sites of interest, the first of which was interesting just because of it's well-laid-out videos (https://www.carcarekiosk.com/video/2.../flush_coolant), but the one of more relevance was this one: http://carspecmn.com/toyota-and-lexu...leeding-trick/.
Although my "upper drain plug" looked a little different, it was in a similar spot (back left of the engine on the passenger side) and could only be seen after removing both the engine cover and the other cover(?) on the left. Using a 10mm socket, I completely removed it and then followed Mesquite77's procedure, minus the clear vinyl tube. It took WAY more coolant than I thought (ultra low), to the point where I wondered if I had a leak or if the "upper drain plug" was actually correct. Eventually, coolant started pouring out and I capped it back and completed steps 4-10. I haven't driven it around yet, as I'm pretty exhausted from the day in its entirety, but it seems that was the contributing problem - so much air in the cooling system that it was overheating almost immediately. Hopefully I didn't do too much damage to the head gaskets, but with it being around 130k miles now, it might be time to change them out anyway.
Just wanted to update y'all in the event someone had a similar problem. Hopefully this makes things easier to search for and find. Take care!
Steps from service manual, key is to fill it at radiator filler neck on driver's side, be careful, that is the hot part...
1) Loosen upper drain plug
2) Put a clear vinyl tube on vent plug located on upper drain plug
3) Fill radiator at filler neck (not overflow tank) until vent tube full
4) Install radiator cap, tight
5) Fill reservoir overflow tank
6) Warm up engine and while it is running squeeze the inlet and outlet radiator hoses by hand several times
7) Stop engine and let it cool
8) Remove radiator cap and check for fluid level in radiator
9) If coolant inside radiator (not overflow tank) is not to full mark, repeat steps 1-8 until it is
10) Top off reservoir tank if needed.
1) Loosen upper drain plug
2) Put a clear vinyl tube on vent plug located on upper drain plug
3) Fill radiator at filler neck (not overflow tank) until vent tube full
4) Install radiator cap, tight
5) Fill reservoir overflow tank
6) Warm up engine and while it is running squeeze the inlet and outlet radiator hoses by hand several times
7) Stop engine and let it cool
8) Remove radiator cap and check for fluid level in radiator
9) If coolant inside radiator (not overflow tank) is not to full mark, repeat steps 1-8 until it is
10) Top off reservoir tank if needed.
Without any help from anyone in determining where the "upper drain plug" was, I did some more research to find two sites of interest, the first of which was interesting just because of it's well-laid-out videos (https://www.carcarekiosk.com/video/2.../flush_coolant), but the one of more relevance was this one: http://carspecmn.com/toyota-and-lexu...leeding-trick/.
Although my "upper drain plug" looked a little different, it was in a similar spot (back left of the engine on the passenger side) and could only be seen after removing both the engine cover and the other cover(?) on the left. Using a 10mm socket, I completely removed it and then followed Mesquite77's procedure, minus the clear vinyl tube. It took WAY more coolant than I thought (ultra low), to the point where I wondered if I had a leak or if the "upper drain plug" was actually correct. Eventually, coolant started pouring out and I capped it back and completed steps 4-10. I haven't driven it around yet, as I'm pretty exhausted from the day in its entirety, but it seems that was the contributing problem - so much air in the cooling system that it was overheating almost immediately. Hopefully I didn't do too much damage to the head gaskets, but with it being around 130k miles now, it might be time to change them out anyway.
Just wanted to update y'all in the event someone had a similar problem. Hopefully this makes things easier to search for and find. Take care!
05-26-19, 09:15 PM
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Yes, as Step 6 states, I warmed up the engine to operating temperature and began squeezing both radiator tubes as required. The car reached normal operating temperature at a much more "normal" rate, although I didn't try to go past it. I'll take it for a drive tomorrow for verification that this was in fact the issue. After seeing the amount of air in the system, I'm pretty convinced this was the issue, but the overheating could've damaged the gaskets, which is now my next worry. We'll see tomorrow!
05-26-19, 09:32 PM
#5
Before you start it again,
check the coolant appearance (cold engine) by removing the radiator cap for signs of oil; and
check the oil level as well as the appearance of the oil on the dipstick and under the oil filler cap for signs of coolant in oil.
check the coolant appearance (cold engine) by removing the radiator cap for signs of oil; and
check the oil level as well as the appearance of the oil on the dipstick and under the oil filler cap for signs of coolant in oil.
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