Prius 04 salvage, overheats/sets p1150 & p1116

Hi Kelly,

Do you hear the coolant heat recovery pump running for 15 seconds or so, after the car is shut down? That is how the canister gets filled up.

If you hear the pump running but the fluid in the canister is not at engine temp, then it is possible that the valve that switches engine coolant to flow to the passenger cabin heater core or to the canister is stuck, so that coolant only flows to the cabin heater core.

Also see the attached message string:
http://priuschat.com/forums/prius-t...ant-heat-storage-thermos-how-do-you-test.html

Note that when you drain coolant from the coolant heat recovery canister drain cock, some of the initial flow is coming from the radiator; hence that fluid will be relatively cold. The engine overheating issue is much more of a concern than the coolant heat recovery canister. Regarding that problem, I am wondering if the engine thermostat is opening. Do you feel hot coolant flowing through the radiator hose leading to the radiator?

If the thermostat is OK, then are the two radiator fans blowing properly so that they are sucking air; or are they blowing air towards the front of the vehicle? I have seen a few posts where the body shop incorrectly installed the fans. Is the serpentine belt in good condition and its tension properly adjusted so that the engine coolant mechanical pump is being driven properly?

Regarding the procedure to refill engine coolant, this can be done without using a special coolant air-bleed tool. I did this for another Prius owner last weekend. However this requires considerable patience. Note the valve on the upper driver's side of the radiator that allows air to be bled as fluid is added. Also note that ~6 quarts of SLLC are required to be added after all three drains have been opened.

Pls see my post #22 from the attached string:
http://priuschat.com/forums/care-maintenance-troubleshooting/30813-changing-engine-coolant-3.html

BTW the correct coolant to be used is the pink Toyota Super Long Life Coolant; not the red Toyota Long Life Coolant. However this should not cause the overheating issues.

Also, are you aware that there is an inspection mode that keeps the gasoline engine running at all times: make the car IG-ON while the gear selector is in P, and fully depress the accelerator pedal 2x. Then shift to N and fully depress the accelerator pedal 2x. Then shift back to P and depress the accelerator pedal 2x. At that point, make the vehicle READY and you will see the hybrid vehicle icon appear in the upper left corner of the MFD. The gasoline engine will remain on. Do not drive the vehicle in this condition as the transaxle can be damaged if the tires slip.

 

Patrick, How do you get it out of inspection mode?

 

Just turn the car to IG-OFF. Next time you make the car READY, it will be back to normal.

 

Does the coolant can get hot on the outside? If so that is an indication that there is a problem internally with the can. You should also check the hose routings are correct and the electric pump and valves are functioning. Check you PMs.

 

Definately sounds like a blockage somewhere--something not flowing... Use one of those laser pointer temp gauges to check temps in the system without having to take crap apart... this should give you your answer quickly and effectively....

 

front end collision usually means there's still air in the system.

you've got a scantool. don't f around with the diy workarounds when you're on shop time.
scantool>
active tests>
water pump active test

activates coolant pump for 30s- will refuse command for that long, and then it will shut off. run this until you stop hearing the air.

use the air bleed valve on top of the radiator. use a 6 mm allen to open that up. down on the side of the radiator there's a little air bleed outlet. watch that until it's running coolant w/o air bubbles.

alternate this w/water pump procedure. it's not easy to bleed coolant in this car, takes some patience.

you can't use a specialty coolant system bleeding tool like w/a regular car, unfortunately. too much vacuum on that system and you can do damage.

that's from my husband, a fellow unbeaten diagnostician and former hybrid tech, over the phone. i only see him a couple weekends a month now since he's back in school.

 

Hi Galaxee,

Regarding engine coolant drain/replace: since the Toyota scantool is used just to run the coolant heat recovery pump, and since it is possible to short the coolant heat recovery pump relay socket terminals to achieve the same end, then from a DIY perspective it appears that there is no advantage to having the scantool available for this particular job. Do you agree?

The air bleed outlet on the side of the radiator is news to me. My 2005 repair manual did not mention this, so I did not look for it. If you've seen this could you please describe where to find it.

Thanks for providing the warning about not using a vacuum bleeding tool to speed up this process. Did DH say how long it should take to do this job, assuming that the tech is experienced and well down the learning curve?

 

oh boy. well i won't be able to get ahold of him for a while so i don't know the answers to all of those questions.

the scantool is a huge timesaver. these guys don't get paid by the hour, they get paid by the job. rather than fooling around taking things apart, they plug it in and press a couple buttons. much simpler. from a diy, sure. i can see that. we have yet to replace our coolant loops because of all the stupid crap that keeps happening to us, but we don't have a scantool and DH isn't afraid of the job.

i'll ask him to clarify the location of the bleed outlet next time we talk. tonight, maybe. i don't remember how long it took him to bleed a prius coolant system at the top of his game, but there is a definite learning curve. for conventional cars, the bleed procedure is made pretty quick and simple with a couple-hundred-dollar adapter and bleed kit. in shop time, the kit pays for itself in time saved pretty quickly. the prius takes a little more effort, as usual.

 

hey galaxee, glad to hear your husband is doing well in search for his better career, must be tough to be only to see each other for a tee wee bit when you were used to seeing him everyday for so long. Be strong!! and thanks again for the wise answers as i'm sure he will excel in his upgrade for success.

I know a coolant job only pays X hours and for the prius you don't get any extra so techs are discouraged from working on hybrids hmm (goes true when bleeding prius brakes, lots of techs thinks its stupid) ... I will confirm that when I go to work again on Tuesday. BTW is a coolant thermometer is a good indicator of coolant life besides the pink color?

Oh and sometimes I remember a Camry Hybrid customer complaining about noise (hissing?) after getting his coolant changed, the techs said due to the complicated nature of the system, you would have to drive it for awhile before all the air is cleared out of the system. Hm is that true or they just lying so they can go bang up other jobs to make up the camry that lost their potential flat rate earnings?

 

After you remove the black plastic cover, you can see that the top of the radiator is covered by body sheet metal. Look for a hole in that sheet metal on the driver's side of the car, and you will see a 6 mm hex fitting within. Use a 6 mm Allen key to open up that fitting, which will allow air to vent out of the top of the radiator.

While you are running the engine to purge out air in the coolant system, did you set the heater temperature control to Max Temp and turn the fan to max speed, so that the heater core will fill up with coolant?

If you are sure that you have filled as much coolant as you can but the engine still overheats, I suggest that you consider removing the engine thermostat and testing it. It is supposed to open at 82 degrees C (180 degrees F). If the thermostat is good, then maybe the mechanical coolant pump has failed?

Your message says that you "zapped pump". This should be done when the car is IG-ON (not READY) and the engine should be off. The pump in question is the coolant heat recovery system pump. When you applied power, did you hear the pump running? It is easy to hear. The purpose of running that pump would be to fill up the canister and associated plumbing with fluid. After that is done, then you would start the engine in inspection mode and continue to purge air out of the system.

If you do not hear the pump running, then check the CHS relay which lives in the relay box mounted to the cowl. One of my prior posts (that I earlier gave you a link to) explains how to short the relay socket terminals to force the coolant heat recovery system pump to run. Then you can see whether you can hear the pump or not.

The hum is the inverter running (when the car is READY), and/or the inverter coolant pump which runs at all times when the car is IG-ON or READY.

 

except that when you do that short like that, you don't have access to the flow control valve. when the car is off, the valve blocks off the path to the chs tank. you can jump the pump, but where is the coolant coming from and going? how is the air going to get out if the valve is closed? the scantool will open the valve when you trip the pump and let the air out.

ok, if you're looking at it from the front of the engine compartment. it's on the rear side of the radiator pointing back toward the engine compartment. the valve is on the LH side (right side when looking into the engine compartment.)
the 6mm hex plug is on top of the radiator, you stick the allen wrench through the frame rail in front. the bleed outlet is directly below. it's metal.

it depends on whether you have to burp the chs tank. if yes, and it all plays out, he can do it in 15-20 minutes. his record is under 10, cycling it 3 times. and he didn't even work at that dealership- the tech handed him the techstream and told him to do it if it's not all perfect on the first shot, more like 30-35 minutes which is fairly average. unfortunately you don't know 100% for sure until you park the car for 5 hours. if there's air, you'll suck it up, the temp sensor cools off from the air, car sets cel. you can be pretty damn sure beforehand, but it happens from time to time where they come back if you send them out too soon.

thanks phil we'll be fine. been through far worse trials that didn't even involve the promise of a better future. this isn't fun but so far so good. hope you and the little family are doing well too.

some places are taking to charging the flush rate for a prius drain and fill to account for the time...

are you talking about the pH dip strip or the hygrometer? as far as DH has been told, neither can accurately test the sllc. it is thinner than the ethylene glycol coolants so the hygrometer readings are off. also, the pH chart that comes with the dip strips won't be accurate.

yes. the camry coolant system is the easiest damn coolant system to bleed ever. including the camry hybrid. he has no idea how you would f up and get air in that system. either something beyond that is wrong with the car or the tech is itching to rack up hours. the tech is bullshitting.

if it's hissing outside the car after the car is warmed up the radiator cap may be loose. if the noise is inside the car, it's probably air in the system. usually that sounds like a gurgle though.

 

OK. Stupid shot in the dark here.

On another thread, a guy had a Prius that had some front end repairs done to it.

There are two fan motors that pull air through the radiators. But, the motors turn in OPPOSITE directions, and the fan blades have OPPOSITE blade pitches.

If they were swapped when the front end was assembled, then instead of having two fans that efficiently suck air through the radiator, you have two fans that inefficiently (because they're both turning backwards) blow air out of the front of the radiator. In his case, this is just what was done. He swapped the sets of fan blades and everything worked out great.

Might be worth checking.

 

Hi Galaxee,

Thanks to you & your DH for considering my questions.

Regarding the flow control valve position, the valve is supposed to direct coolant flow to the cabin heater core (and sometimes the canister as well) when the engine is running. When the engine is turned off, the valve is supposed to direct coolant flow to the canister for preheat as well as storage operation (see for example, page 05-287 in the 2005 repair manual.) Therefore I assumed that the valve would remain in that position after the coolant heat recovery system pump stopped operating and the car remained IG-OFF.

Perhaps this assumption is not valid; however we were successful in refilling the engine coolant system. I recall that DH was planning to change the engine coolant on your Prius without access to the scan tool. What was his plan to deal with this issue?

Regarding the radiator bleed valve, I know the valve that is accessible from the top LH side and can be opened using the 6 mm Allen key. Is it correct that this valve and the drain cock located on the LH bottom of the radiator are the only valves associated with the radiator?

20 minutes for doing the job is amazing; we probably spent 1.5 hours or more working on getting all air out of the system.

 

patrick-
he left all of his training materials here so he directed me to the hybrid system training book, course 071 page 4-14. during storage (ig-off), the valve provides a path between the heater core and the head, but the chs circuit is blocked off.

i don't recall how he was going to do it. he didn't say much other than that i'd get it once he showed me.

will get back to ya on the other stuff.

re: the time... that's why diy and professional wrenching are on vastly different scales. this is also why in a big shop, scantools are worth the investment. in that 1.5 hours, DH could have gotten the prius out the door and made a couple bucks on that, moved on to a good juicy maintenance ticket to put some real hours on his paycheck, and maybe even been moved on to the next car. this is the pace that is expected of you in the shop, and if your bay doesn't produce the profits... the inhabitant of that bay is replaced. the emphasis is always more work in less time when there's work laying around waiting to be done. it deserves all the criticism it gets...

TLK- good luck with getting this worked out- will let you know what DH says again next time i talk to him.

 

Thanks, Galaxee. Regarding p. 4-14, figure 4.19, I agree that the illustration shows that the valve does not route flow to the canister, and that the water pump is "off". However that does not make sense since the water pump in fact does run for several seconds to fill the canister, when the car is shut down.

I've attached the page from the 2005 repair manual that I had previously cited, which shows that the valve is open between the engine and the canister when the car is IG-OFF. This appears to contradict figure 4.19 from course 071.

For those who are following along, course 071 can be downloaded at Automotive Training and Resource Site

The file is Hybrid04 Engine.pdf

 

the pump active test isn't the engine water pump. that's for the chs pump. if you can run that on active test, then the pump functions. if you're not sure, reach back under the wheel well cover and rest your hand on the pump, trigger the active test.

could be the flow valve is screwed up if you're not getting hot coolant in the tank, and if it's not keeping the coolant hot for very long if hot coolant is getting in there, he's worried about the integrity of the chs tank.

 

could be this is what happens AFTER the water pump fills the tank. note the pump is OFF but hot coolant is already in the chs tank. this clearly is the state *after* coolant has been pumped into the tank. isolating the hot coolant would be a good idea, after all. the running pump to fill the tank is just a few seconds of operation and not the permanent state while the car is off.

would it contradict or would this be looking at when the coolant loop is open to allow coolant to enter the tank? it is concerning the operation of the valve, which would make the open position during transfer more relevant to the topic at hand there. it even says storage operation (after power switch off.)