Update & solution: I found that I had an aftermarket radiator cap with an out of spec pressure rating, and a number of leaky hoses including PHH, throttle body and others. I bought an OEM cap replacement and replaced pretty much all hoses (PM me for details if wanted), and it's been running awesome ever since. Thanks for the insights to help figure this out.
I've been spending quarantine casually trying to track down what's wrong with my car. I think I found out the bulk of it today, but I'd be grateful for feedback and thoughts.
The short of it is:
- I have a confirmed coolant leak, currently not leaking
- Car started running hot
- Refilled coolant, levels dropped after driving with no leak present
- Coolant levels stabilized
- I think I lost coolant to the leak, and that after refill, levels dropped from burping, and that I do not have a blown HG.
And the long story is
I took my 97 out to the desert back at the end of February. After about 2.5 hours in the car, when I got into town the AC shut down, but I did not see the needle move. On the way back, with AC off I started getting close to redlining up a steep grade.
I'd had fan clutch on my list for a while, so that was replaced when I got back and thought that'd be the end of it. However around town I started overheating at low speeds, with the new fan clutch. I noticed around then I had a leak just behind the driver side wheel. I caught some in a bowl and it was red/pink. At first I thought steering fluid, given a whirring I developed and needed to top off, but I'm certain it was Toyota Red.
At this point (not when the AC went off in the desert, not when I overheated coming back, not before replacing the fan clutch) I checked coolant levels. You could see radiator fins. I ordered some Toyota coolant, and topped it off. It took about half a gallon at first.
I drove around the neighborhood, everything was fine. I come back later, no leak. However coolant was low, this time about a quarter gallon.
I called my mechanic and asked about what an engine rebuild looks like, at this point being convinced it's HG. They said don't get carried away yet, that's a lot of coolant to be burning up with no symptoms, leak or no leak visible. And they knew about the previous coolant leak, and suspected PHH.
I drive again, no leak, coolant low about an eighth of a gallon. I drive again, no leak, coolant low this time a tiny bit. Drive again, no leak, coolant at the right level.
My current diagnosis is a leak, probably PHH, that over time diminished coolant levels enough that I'd approach overheating under certain conditions (high stress, low speed). This led to air in the pipes and burping as I drove it and added coolant until I reached my current stabilized levels. The leak is currently not leaking, but a pressure test should narrow it down. No new engine today.
Curious what you all think, if I'm missing anything important. I figure I need a new engine some day, and I'd rather not have it happen on a trip, so if I'm biasing thinking toward the simple/low cost solution, I'd rather learn it now.
Thanks in advance.
I've been spending quarantine casually trying to track down what's wrong with my car. I think I found out the bulk of it today, but I'd be grateful for feedback and thoughts.
The short of it is:
- I have a confirmed coolant leak, currently not leaking
- Car started running hot
- Refilled coolant, levels dropped after driving with no leak present
- Coolant levels stabilized
- I think I lost coolant to the leak, and that after refill, levels dropped from burping, and that I do not have a blown HG.
And the long story is
I took my 97 out to the desert back at the end of February. After about 2.5 hours in the car, when I got into town the AC shut down, but I did not see the needle move. On the way back, with AC off I started getting close to redlining up a steep grade.
I'd had fan clutch on my list for a while, so that was replaced when I got back and thought that'd be the end of it. However around town I started overheating at low speeds, with the new fan clutch. I noticed around then I had a leak just behind the driver side wheel. I caught some in a bowl and it was red/pink. At first I thought steering fluid, given a whirring I developed and needed to top off, but I'm certain it was Toyota Red.
At this point (not when the AC went off in the desert, not when I overheated coming back, not before replacing the fan clutch) I checked coolant levels. You could see radiator fins. I ordered some Toyota coolant, and topped it off. It took about half a gallon at first.
I drove around the neighborhood, everything was fine. I come back later, no leak. However coolant was low, this time about a quarter gallon.
I called my mechanic and asked about what an engine rebuild looks like, at this point being convinced it's HG. They said don't get carried away yet, that's a lot of coolant to be burning up with no symptoms, leak or no leak visible. And they knew about the previous coolant leak, and suspected PHH.
I drive again, no leak, coolant low about an eighth of a gallon. I drive again, no leak, coolant low this time a tiny bit. Drive again, no leak, coolant at the right level.
My current diagnosis is a leak, probably PHH, that over time diminished coolant levels enough that I'd approach overheating under certain conditions (high stress, low speed). This led to air in the pipes and burping as I drove it and added coolant until I reached my current stabilized levels. The leak is currently not leaking, but a pressure test should narrow it down. No new engine today.
Curious what you all think, if I'm missing anything important. I figure I need a new engine some day, and I'd rather not have it happen on a trip, so if I'm biasing thinking toward the simple/low cost solution, I'd rather learn it now.
Thanks in advance.
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