Coolant leak, random overheating..Need help guys
#1
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Lexus Test Driver
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From: College Station, Texas
Coolant leak, random overheating..Need help guys
All I can say to this point is this car is seriously pissing me off...to the point of me feeling helpless. I bought it in May and since have put in new spark plugs, wires, caps, rotors, coils, water pump, timing belt, thermostat, and every seal involved with the tb/wp service, PCV valve, valve cover gaskets, complete fluids flush, and steering rack.
Now this....keep in mind my heater doesn't exactly work until about 15 minutes of driving...and my idle air control valve is bad.(turn A/V off and car stalls) I recently started to notice early in my commute, the temp gauge would start to climb. But then I would either let off the throttle of give it a good punch and it would immediately return to normal. Runs butter smooth. Then, this weekend I took it on a 4 hour trip to Dallas(ran perfect..no hiccups ever). Next day after arriving in Dallas, 5 minutes after leaving my friends house, I'm in slow-n-go traffic and the temp starts climbing again. Right then my exit comes up and I punch it...needle immediately goes to normal. 4 hours back home and the trip is butter smooth. I pull in the drive, unload the luggage, and then move the car. That's when I notice a puddle. I thought it was PS fluid but closer inspection today leads me to believe coolant(red). I thought PS fluid because it was all over the area of the rack. But, it is not as thick as PS fluid and it smells just like the red coolant in my resevoir.
This evening I go drive 10 minutes for gas. Needle creeps up after about 8 minutes of driving. I punch it again and the needle drops. (then my heat starts working) Seems to be a common theme of once the temp climbs and then drops, the heat starts working. I come home back in the drive and put it park...guess what? Needle starts climbing again. Yes I have white smoke at start up and yes it smells like coolant. I initially just thought it was condensate due to it being cold. The coolant is leaking on the drivers front of the engine...getting on parts of my steering rack, oil filter and cross member that sits right under the front oil pan.
SO now Im WTF??? I can drive 8 hours at 70mph and run butter smooth but I randomly "overheat" in the driveway or 10 minutes in to my commute. I'm taking it in tomorrow to get a compression check. I can't see the leak..only where it splashes. Better not be a BHG because then I will really be upside down in this car.
Now this....keep in mind my heater doesn't exactly work until about 15 minutes of driving...and my idle air control valve is bad.(turn A/V off and car stalls) I recently started to notice early in my commute, the temp gauge would start to climb. But then I would either let off the throttle of give it a good punch and it would immediately return to normal. Runs butter smooth. Then, this weekend I took it on a 4 hour trip to Dallas(ran perfect..no hiccups ever). Next day after arriving in Dallas, 5 minutes after leaving my friends house, I'm in slow-n-go traffic and the temp starts climbing again. Right then my exit comes up and I punch it...needle immediately goes to normal. 4 hours back home and the trip is butter smooth. I pull in the drive, unload the luggage, and then move the car. That's when I notice a puddle. I thought it was PS fluid but closer inspection today leads me to believe coolant(red). I thought PS fluid because it was all over the area of the rack. But, it is not as thick as PS fluid and it smells just like the red coolant in my resevoir.
This evening I go drive 10 minutes for gas. Needle creeps up after about 8 minutes of driving. I punch it again and the needle drops. (then my heat starts working) Seems to be a common theme of once the temp climbs and then drops, the heat starts working. I come home back in the drive and put it park...guess what? Needle starts climbing again. Yes I have white smoke at start up and yes it smells like coolant. I initially just thought it was condensate due to it being cold. The coolant is leaking on the drivers front of the engine...getting on parts of my steering rack, oil filter and cross member that sits right under the front oil pan.
SO now Im WTF??? I can drive 8 hours at 70mph and run butter smooth but I randomly "overheat" in the driveway or 10 minutes in to my commute. I'm taking it in tomorrow to get a compression check. I can't see the leak..only where it splashes. Better not be a BHG because then I will really be upside down in this car.
Last edited by FireCode; 01-23-11 at 07:26 PM.
#2
1. Make sure your cooling system is full, no air pockets.
2. It sounds like you might have a sticking thermostat.
3. This is the biggie, check your cooling fan. It looks like whenever you are driving slow it overheats but on the highway its fine, thats a big indicator of a bad electric fan or on a belt driven fan a bad fan clutch.
2. It sounds like you might have a sticking thermostat.
3. This is the biggie, check your cooling fan. It looks like whenever you are driving slow it overheats but on the highway its fine, thats a big indicator of a bad electric fan or on a belt driven fan a bad fan clutch.
#3
When you are driving at 70mph the air is cooling down the system but idle it is not. Normally I would assume that is a broken thermostat or air pockets in the system but you already told us you are leaking coolant so obvious that is the problem. The obvious answer is to pop the hood and find where the leak is coming from.
#4
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That would be the obvious answer but I can't find where it is starting from...somewhere right above the steering rack and then it blows back on the front oil pan where it burns off. The big question is..is the coolant leak and overheating related...When driving, after the temp spike and I punch the gas, the needle drops back to normal and stays there. Even If I enter back into slow-n-go traffic.
#5
The leak isn't helping as it allows for air pockets in the system, are the directly related ? Who knows, it depends on whats leaking. Crank the car and let it warm up and watch for leaks, that way the wind isn't blowing coolant everywhere. If you still don't see it get some uv dye and a small blacklight, I use mine for AC work and saved myself about $250 in one fix.
#6
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1. Make sure your cooling system is full, no air pockets.
2. It sounds like you might have a sticking thermostat.
3. This is the biggie, check your cooling fan. It looks like whenever you are driving slow it overheats but on the highway its fine, thats a big indicator of a bad electric fan or on a belt driven fan a bad fan clutch.
2. It sounds like you might have a sticking thermostat.
3. This is the biggie, check your cooling fan. It looks like whenever you are driving slow it overheats but on the highway its fine, thats a big indicator of a bad electric fan or on a belt driven fan a bad fan clutch.
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#8
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I gotcha man. I am going to take it in in the morning to see if the shop can trace the leak. I am going to have them do a compression check or leak down test to see if my HG is still good.
#9
You say that when you turn the AC off it overheats, most newer cars have a dedicated electric fan that runs when the AC is on. If the engine is up to temperature the engine cooling should kick on. If you car overheats when you turn the AC off the engine cooling fan isn't working.
#10
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You say that when you turn the AC off it overheats, most newer cars have a dedicated electric fan that runs when the AC is on. If the engine is up to temperature the engine cooling should kick on. If you car overheats when you turn the AC off the engine cooling fan isn't working.
#12
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Getting it pressure tested today. On a cold start, the needle goes to warm and then a few seconds later while driving, it continues on up to hot. When that happens, I hit the gas, and instantly my heater starts working(blows ice cold up to that point brrr.) and the temp gauge reads normal...Thinking air in the system or the heater control valve is really effed up
#13
If you come to a stop again, like at a red light does the heat blow cold again ?
If while moving or revving the engine you have heat but when the engine is at idle you don't there is definitely air in your system.
If while moving or revving the engine you have heat but when the engine is at idle you don't there is definitely air in your system.
#14
the heating system gets its heat off of the coolant, not getting proper heat is a known symptom on the SC for having a very low amount of engine coolant (or a NHG). you are 100% low on fluid if you are leaking fluid all over the place (sounds redundant right).
Have you even checked your fluid level in the radiator yet? Is the overflow bottle bone dry?
I would recommend topping it off every trip you make until you find & stop the leak. Since you are still getting some heat you still have a bit of coolant in there and you should not let it get any lower or you will actually get to the point that punching it wont help much, then overheat, and thats no good.
fill the coolant to the max, wipe down the suspect areas where the leak could be coming from with a dry towel, turn the car on, grab a flashlight and try to spot the leak.
https://www.clublexus.com/forums/per...-to-start.html
https://www.clublexus.com/forums/per...t-working.html
Have you even checked your fluid level in the radiator yet? Is the overflow bottle bone dry?
I would recommend topping it off every trip you make until you find & stop the leak. Since you are still getting some heat you still have a bit of coolant in there and you should not let it get any lower or you will actually get to the point that punching it wont help much, then overheat, and thats no good.
fill the coolant to the max, wipe down the suspect areas where the leak could be coming from with a dry towel, turn the car on, grab a flashlight and try to spot the leak.
https://www.clublexus.com/forums/per...-to-start.html
https://www.clublexus.com/forums/per...t-working.html
Last edited by Ali SC3; 01-24-11 at 01:35 PM.
#15
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As far as my coolant level, the resevoir is completely full. My leak is small and just started, but apparently it's enough to cause an issue. Makes me wonder if everything was tightened back up properly from the timing belt/ water pump service that included a coolant flush. That service was completed in November.