Recommended Posts

Hello! My name is Jake and I have an 04 RX330 with 230,000 miles on it. Not certain on the history of it but I have gotten it with no heat and an overheating problem(EDIT: previous owners said it has overheated on them). I immediately knocked out the easy stuff, checked coolant levels, verified fans were working. So I end up doing serious work that it needed: waterpump, timing belt, power steering pump, upper/lower intake gaskets, thermostat(THM 117-$11.32 at napa), valve cover gaskets, spark plugs. I end up finding smoke swirling out of a crack in the radiator while the car was idling for an hour during a fuel injector decarbonizing process. I end up replacing the radiator as well as the fan motors with the relay because the fans wouldn't turn on. I ended up using a power probe straight to the old fan motors and only fan #2 worked. I end up putting it all together-bled all of the air out of the cooling system with an airlift evacuation tool-and this thing is still overheating! Today I pulled it in and put the scantool on it-temp reads 244 degrees, so it's up there. I take a laser thermometer gun and the passenger-side (or upper hose) of the radiator read 183 degrees give or take and the part of the intake that the sensor screws into was around the same. So I thought it's only a $20 sensor, and replaced it-also considering it had a previous P0117 code(engine coolant temperature circuit low input). I know when the DTC is aiming at the input part of a circuit, it's talking about something with the sensor. I thought this would do it, BUT the car still overheats via gauge. Good news was I had heat, so I'd blast it when it starts climbing up and it'd slowly go down. I'm really stumped now, because I know the heater core acts as a mini radiator, but it doesn't make sense that the heatercore cools the engine down but not the fans and radiator being fully functional. The upper heater hose is piping hot with pressure but the lower hose is room temperature with pressure, I verified by squeezing the hoses. Is the thermostat defective? I installed it with the wobbler pin positioned at the top via installation instructions. I feel like I might run a compression test tomorrow to check the head gaskets, but I feel like I'm missing another sensor or something-I'm a freshman in college so anyone with experience I'd greatly appreciate it! 

Share this post


Link to post
Share on other sites

sounds like the heater core is plugged with the temp differences between the 2 hoses.

Share this post


Link to post
Share on other sites

A coolant check should reveal whether a head gasket is leaking and subsequently superheating the coolant.

Share this post


Link to post
Share on other sites
On 2/13/2018 at 11:34 PM, 04lexusrx33O said:

Hello! My name is Jake and I have an 04 RX330 with 230,000 miles on it. Not certain on the history of it but I have gotten it with no heat and an overheating problem(EDIT: previous owners said it has overheated on them). I immediately knocked out the easy stuff, checked coolant levels, verified fans were working. So I end up doing serious work that it needed: waterpump, timing belt, power steering pump, upper/lower intake gaskets, thermostat(THM 117-$11.32 at napa), valve cover gaskets, spark plugs. I end up finding smoke swirling out of a crack in the radiator while the car was idling for an hour during a fuel injector decarbonizing process. I end up replacing the radiator as well as the fan motors with the relay because the fans wouldn't turn on. I ended up using a power probe straight to the old fan motors and only fan #2 worked. I end up putting it all together-bled all of the air out of the cooling system with an airlift evacuation tool-and this thing is still overheating! Today I pulled it in and put the scantool on it-temp reads 244 degrees, so it's up there. I take a laser thermometer gun and the passenger-side (or upper hose) of the radiator read 183 degrees give or take and the part of the intake that the sensor screws into was around the same. So I thought it's only a $20 sensor, and replaced it-also considering it had a previous P0117 code(engine coolant temperature circuit low input). I know when the DTC is aiming at the input part of a circuit, it's talking about something with the sensor. I thought this would do it, BUT the car still overheats via gauge. Good news was I had heat, so I'd blast it when it starts climbing up and it'd slowly go down. I'm really stumped now, because I know the heater core acts as a mini radiator, but it doesn't make sense that the heatercore cools the engine down but not the fans and radiator being fully functional. The upper heater hose is piping hot with pressure but the lower hose is room temperature with pressure, I verified by squeezing the hoses. Is the thermostat defective? I installed it with the wobbler pin positioned at the top via installation instructions. I feel like I might run a compression test tomorrow to check the head gaskets, but I feel like I'm missing another sensor or something-I'm a freshman in college so anyone with experience I'd greatly appreciate it! 

You could still have an air bubble in the system.

Share this post


Link to post
Share on other sites

Wife's car (RX400H) has the same issue.  I don't understand how blasting the heat has a significant effect on the coolant temperature.  Does a head gasket leak itself cause a car to overheat or is it due to loss of coolant?  Coolant levels (radiator and overflow) are fine so how would a head gasket cause overheating in this case?

By the way, the car's first issues were shaking at 40mph and a check engine light related to cylinder mis-fire.  Blue Devil treatments were done but not effective.

 

Share this post


Link to post
Share on other sites

Blasting the heat removes heat from the coolant. A head gasket leak injects super-heated air directly into the coolant. 

A bad radiator cap can also cause an overheating condition if the cap cannot maintain sufficient cooling system pressure.

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...

  • Similar Content

    • By Kie
      Hi!
      Have any you guys had a problem with the Rack&Pinion?
      I went to the car service around my house(Knoxville, TN). They told me mine is leaking and needs to be changed. 
      I'm having a hard time deciding to change or not because it cost like 1500$
      Do any of you have recommendations or any other place I should have service?

      Thanks!
    • By xxiLexus
      So I recently went out of town and let my cousin drive my car for about 5 days, however when she returned the car to me I noticed the USBs under the arm rest aren't working anymore. I used to always play music via USB (and bluetooth sometimes) and charge at the same time. I've found an alternative to this which was utilizing the cigarette lighter port and buying a USB cigarette lighter device. Im thinking its fuses that went bad or got fried but if anyone knows a fix to the USBs not working that'll help me! Thanks! 
    • By Michael17
      Listing can be found on Ebay.

      LOW MILEAGE 1995 Lexus SC 400. Looks and drives like perfect! Great condition inside and out. Very nice sports coupe soon to become a classic. Garaged with solid maintenance records. 
      New tires (just replaced)
      New battery (just replaced)
      New plugs and wires (just replaced)
      New brakes and rotors (@124k)
      Timing belt replaced (@88K)
      water pump replaced (@88K)
      Engine mounts and transmission mounts (@124k)
      Updated Cat-Back exhaust system
      Much more…

      Smooth riding sports car! Bullet proof engine and very reliable luxury automobile. Nonsmoking vehicle, no wrecks, clean Carfax. Title in hand. You will not be disappointed. Original sticker price in 1995 shows $52,413. Serious inquiries only please.










    • By Lexus Owners Club
      The Lexus RC F GT3 secured a sensational first victory in the Blancpain GT Series at the Paul Ricard circuit in the South of France on Saturday. Emil Frey Lexus Racing’s Alberto Costa Balboa took the lead just half a lap from the chequered flag in the six-hour Endurance Cup race to claim a memorable result for the team and for Lexus
      The result sets the seal on a steady transformation of the team’s fortunes in the RC F GT3’s first full season of European GT competition and delivers on the promise the car showed in scoring points and podium results in the previous rounds of the series at Brands Hatch and Silverstone.
      Lorenz Frey, Team Principal, said: “We still can’t believe it. The last lap was nerve-racking, nobody would have thought that after six hours it would be so close. We have now definitely proven that we have a very strong package and can demonstrate the performance of the Lexus and the expert work of our team.”
      The race was rare in offering so much close action throughout its 1,000km distance. In a field of 51 starters, just one second covered the qualifying times of the top 24 cars. At the start, Christian Klien in the No14 Lexus moved from fourth on the grid to second by the first corner, while team-mate Stéphane Ortelli in the sister No114 car also put in a strong first stint, racing from eighth to third within just a few laps.

      At nightfall, both Lexus RC F GT3 looked on course for a podium finish. Norbert Siedler in the No114 had a strong fight with the No7 Bentley, but light contact meant he couldn’t progress beyond fourth before handing over to Ortelli. He too suffered contact with another car, which required an unscheduled pit stop to repair damage to the steering. This effectively ruled the Lexus out of contention, but the team were able to use the remaining hours to test and prepare the car for the highlight of the season, the 24-hours of Spa.
      Meanwhile, Marco Seefried was running in a good fourth spot in the No14 car when he handed the wheel to Costa Balboa for the last hour of the race. Once the leading No72 Ferrari suffered an engine failure and the second-placed McLaren received a drive-through penalty, the Lexus found itself running in second place. Costa Balboa was just 0.8 seconds behind the leading Bentley with eight minutes to go. On the final lap, he seized the initiative with a great overtaking move through turn 10, securing an incredible first victory for Lexus in the Blancpain GT Series.
      Emil Frey Racing now leads the Endurance Cup team’s championship standings. The next outing for the team will be a two-race Sprint Cup meeting at Misano, in Italy, from 22 to 24 June.