Coolant Loss, maybe Head Gasket?

Hello, everyone I have a sudden loss of coolant in both resevoirs. I have checked everywhere under the hood, and I have found no leakages whatsoever. I have checked all hoses and all is well. Recently I have been getting some inexplicably poor fuel economy, as well, I noticed on my last oil change some strange beige looking peanut butter looking stuff under my oil cap, but I think that may be related to something I do not want to even think about. At the time I did not suspect anything, but cleaned it. However does anyone out there think that this might be a head gasket issue? If it is, I am selling the car as I cannot hope to afford replacing that at Toyota, and I will not trust any backyard mechanics touching the internals of the Prius. Anyone have this issue or can offer any help. I am so worried right now. Help! Oh and in case you were wondering it is a 2002 Prius.

 

Well I found out what it was. Apparently my Toyota Technician told me that the recent trip to Florida was the root cause. From what was explained, the Prius when transitioning from the very cold state of Kentucky between my next fill up at Jacksonville Florida, the temperature variation caused the computer to get crazy readings. This caused the rad fluid to pressurize and thus caused fluid to spill out while I was driving on the highway. I now remember commenting to my wife that I thought the "Stupid GMC Suburban" was reeking of burning coolant, in the end it was my car. But the kicker is when the Prius is restarted it senses the temperature variation and reacts accordingly. The tech knows this as he has a 2004 and says he drives to Florida regularly and experiences the same issue each and everytime.

Interestingly, he says that 2004 ato 2006 Prius' are prone to this happening when transitioning from Extreme Cold to Extreme Heat without stopping. 2007-2009 do not have this issue as Toyota has recalibrated the software to compensate for this, and the Prius now checks for these conditions.

Of even more interesting news, my father who is a proud owner of a 2006 Toyota Highlander Hybrid, suddenly became curious and checked his fluid level.... wouldn't you believe it... SAME PROBLEM!!! Not as low as mine, but both the inverter coolant and the Engine Coolant were both very low.

Well I hope this helps other people out there. Any thoughts?

 

I should mention that my father came with us to Florida as well, that is how it happened to his Highlander.

Oh and for all us Classic owners out there, I was told to use Toyota Long Life Coolant, mixed to 60% Coolant/40% Water, not 50/50. This works for both the inverter coolant and the engine coolant as they are the same. The tech did not charge me for diagnostic and only charged me for the bottle and told me that I could do it myself. Really great guy!

For you 2nd Gen Prius owners its Toyota Super Long Life Coolant. Mix is already pre-mixed for you at 50/50.

 

Well assuming both of you are correct (which I am not saying you aren't!!! I don't really trust Toyota Tech's at all after my nav system experience), but if its a head gasket, then this means I will sell this car. He told me that in replacing a head gasket on a prius would cost in excess of $2200 + tax. I am not interested in forking over that kind of money. It seems that my past two Toyota's have been so unreliable its rediculous. My 1999 Corolla spent more time in the shop with a failed Engine ECU, then tranny ECU, then Right front suspension went, the wheel bearings. All of this in only 36,000 kms. Now this Prius with a potential head gasket issue is complete garbage.
I have a 2002 Chrysler Neon that I have had nothing but oil changes and gas for 7 years. Its been absolutely bullet proof. Nothing replaced... ever. My Prius has been a pain like no other. The Inverter has been replaced (covered under warranty), the O2 sensor failed, the Hyrbid ECU under the hood went too (warranty!), then the rear defroster failed, then Daytime Running Lights relay mysteriously burned out... I am getting really tired of this car. It only has 62,000 miles. My 2002 Neon same year, has 119,000 miles with no problems. I will have to watch carefully but if it is, I will never buy a Toyota ever again. Plus cost of parts is insane! I mean 120 for a head gasket... are you kidding me? 275 + tax for a new 12V battery? No way... Prius may have saved me money on fuel, but it more than sucks it back in replacement parts.

 

It just drives me nuts because I like this car otherwise. Oh I am even looking at it outside right now in about 2 inches of snow, and I can't help but love the car. But I just can't get over there reliability issues.

I really think that this generation of Prius was not made to handle Canadian winters. Other classic owners I have spoken to in Toronto complain of similar issues. We all still like our cars, but its too bad.

However, for whatever reason, I drove 200 kms since yesterday and the fluid level is perfect no drop whatsovever, so while that Toyota tech may be wrong in some people's opinions (and again they may not be wrong), it seems to be working just fine now. Plus the car seems to warm up a lot faster too!

 

There seems to be some confusion here. The issue is a very rare occurence and happens over extended periods of time, not short trips. This condition allegedly occurs when the cars starts off from a very cold temperature (example when I left Toronto, it was 5°F). When I filled up in Kentucky where this issue really began it was roughly 4°F, and from there I drove all the way to Jacksonville without stopping. The temperature that day in Jacksonville was an awesome 85°F!!! The computer then thinks its gradually overheating and the pump apparently behaves very strangely for both the inverter coolant and engine coolant. The excessive pressures cause the fluid to leak out of the overflow's of each resevoir. There is evidence of this now that I look more carefully there are indications of some residue all over the back side of the bottle. Therefore I believe this adequately explains my dramatic loss of coolant for both my dad's HiHy as well as my poor Prius.

Mind you the car was simply incredible and my fears of it having a heart attack up the mountains was groundless. Total cost for my trip was an unbelievable $66 going there and $59 coming back! The car was awesome and quite the bladder buster. I guess that K&N filter and those new Bosch Platinum +4 Fusions really did the trick! My trip average was about 850-920 km's per tank!!! And that was doing about 72-80 mph most of the way. Since I did just those two mods I find that I get my best mpg around that speed. Well over 50 mpg in most cases.

 

Oh and thats between 500-550 miles per tank for you american viewers!

 

Well it has not happened since. And yes I noticed the "peanut butter" before the trip, but at the time I just attributed it to the previous few weeks of short 10 minute city driving stints I was doing. I know this happens to some cars because of condensation buildup that occurs when the engine warms up then shuts down before having time to evaporate that out. At any rate, I cleaned it and have not seen this since. I just checked it today and it is totally clean, and also why the Toyota tech said that it was just coincidence, nothing related. But I just drove another 60 miles home today, checked when I got home, and the level is fine. So I guess that Toyota tech was right. If its a head gasket it would have surely started guzzling after over 300 miles. The oil looks great too, its still a golden brown.

Patrick, I just want to thank you for your support. I knew when I bought this car that I would be a pioneer and would certainly have to swallow a few problems. It is just that as this car gets older, throwing money like that at it becomes increasingly difficult to justify. My Prius restored my faith in Toyota, especially after the disastrous experience with that POS Corolla LE I had. However, I have since calmed down on my poor Prius, and realize it has indeed been a great little car. I guess that is the price I paid for being among the first Prius owners out there!

 

Nope my Prius has never once overheated! Thankfully. Again, I did find dried coolant behind the bottle. Not sure when this happened. could have been before or after. I rinsed it off.

However, I took the car for a compression test at Toyota this morning at 7:00am as per advice. I just got a call at 10:35am, and again THANKFULLY, the car passed. They told me everything is totally within tolerance. They are checking all hoses, connections and will look into using a scope if the results are inconclusive. In an excellent gesture, and because of the strangeness of this occurance, they will not charge me for the scope. They said my motor looks great, and oil condition is fine. Boy its expensive to do the compression test, but worth the peace of mind. Thanks guys for your advice again. I know you guys are just trying to help me!

I told the technician about your comments so far, and he said that while he agrees it makes no sense, the fact is that it happens every year, only whenever he goes to Florida. But he says the last year he took more frequent stops and his last trip he avoided this drop in coolant.

Further, the fact that three different Toyota Hybrid vehicles do it, my 2002 Prius, a 2006 Toyota Highlander and 2004 Toyota Prius do it, means it cannot be just coincidence. Mechanically it makes no sense, but I am confidant that the Toyota tech knows what he is talking about being a Prius owner.