Attention: If you have a squeaky CHS water pump! New TSB

Argh. I had this done to my car this past weekend.

I just checked my radiator reservoir.
Bone. Dry. Empty.

Looks like they didn't bleed the air out of it right.

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update: I've taken it to the dealer today (1/29/2010) and the guy topped it off and the mechanic said there was "an air pocket"... and he dropped my average mpg by .1 ARGH. I have no idea if he re-drained all the coolant or if he just topped it off.

I remain unconvinced that the problem is fixed because I hear water gurgling around the engine when the engine starts... I'm also worried because the coolant temps are now reading in the 85c degrees mark... But then again, this could stem from the car being in inspection mode for the past 20 minutes or so... I'm noticing that the temp rises really fast.. but again, it could be because they had warmed up the engine and such... Oh, and lower grill is completely unblocked. It's also 30f outside. I'm very worried at the moment. I've never seen such high temps without any grill block in such cold weather. I'll doublecheck the temps on my commute home... after the car has had time to cool down and give me a fresh baseline to compare to.



Oh, and wanna guess what the mech said initially to my concerns of the reservoir being empty? "It pumps the coolant out of the engine and into the thermos, it should fill back up after you turn on the car"

I think I'm going to need a different service adviser/mechanic team if I can't fix this myself.

 

Hi Bob,

My post #42 in the following string provides some info about how to DIY: http://priuschat.com/forums/gen-ii-...13-changing-engine-coolant-5.html#post1046576

You are right that the sound of air bubbling around (likely in the heater core) is proof that the engine cooling system still has air trapped. Suggest you put your car into inspection mode, set the cabin air temp to MAX HEAT and turn the vent fan to a high speed, then rev up the engine for several minutes until you no longer hear air bubbling around.

Don't worry about the fact that your MFD mpg indication is dropping, it is more important to get the air out of the engine coolant system. (In fact, if it only dropped by 0.1 mpg, that is evidence that little effort was expended to get air out of the system - if the MFD mpg reading is for the most recent tank of gas...)

How does the CHRS pump sound when it is operating at the time of shutdown? If you hear air bubbles at that time, you'll have to run the CHRS pump manually when the car is IG-OFF, to fill the canister with fluid so that the air will move up into the radiator, allowing you to purge it out.

Continue to check coolant level in the reservoir and refill when the engine is cold, until the level no longer drops down. Good luck.

 

I thought the heater core only had hot coolant flowing through tit when the heat is on? I'm probably wrong, but that would explain the gurgling I hear when the engine starts up.

Well, I haven't noticed any bubbling sounds from the CHRS pump... yet. So I have some faith the tech managed to bleed most, if not all, the air from that.



Oh and the loss of .1 mpg was from my lifetime average - which equates to approx 1 gallon of gas used.

Heres another question: Does the Radiator cap need to be off when purging the air?

 

Hi Bob,

OK, one gallon of fuel is a lot more than I would have expected to be consumed.

In principle the heater core should have coolant flow only when the heat is turned on, but the control valve might not be 100% effective in shutting off the flow. Further, you might be hearing air in locations besides the heater core.

I do recall hearing air bubbles when I first started to purge air out of the system by running the cabin heater and revving up the engine; but the bubbling went away after a few minutes.

When you rev up the engine, some coolant will come out of the radiator cap opening if you have the coolant level full to the neck, when at idle. So it might be helpful to put the cap on when you are revving up the engine to avoid coolant loss.

Be careful and open the cap slowly when you want to check the fluid level, so that any built-up pressure is released into the overflow reservoir and does not result in hot fluid shooting up from the radiator opening, then burning you, etc.

 

Thanks for the advice Patrick,

Out of curiousity... is there any risk of doing the "air bleed" while actually driving the car? Assuming, of course, that the coolant flow is sufficient enough to keep the engine cool?

Just thinking that the engine temps looked fairly normal, so I just might floor the accel when merging on the highway (aiming for over 3000rpm) while turning on max heat when the water temp is high enough to open the thermostat.

 

Sounds like you have a ScanGauge and can monitor engine coolant temp, so this in principle should be OK. Suggest you make sure the engine coolant level in the radiator and overflow reservoir are both full, when the engine is cold, before you start.

However, you'll have to maintain engine RPM at a high level for a fairly long period of time, so this is why I suggest you do this via inspection mode when the car is sitting still.

 

Thanks, galaxee, for providing the TSB link. My transfer pump made squawking sounds in cold weather, and several complaints to the dealer over two winters always produced the response that they could hear nothing wrong. After leaving the car overnight and receiving the same response, I found your post and returned to the dealer with a copy of the TSB in hand. They (supposedly) had a replacement pump in stock, and wanted to keep the car overnight. I said I would wait, and they (presumably) replaced the pump in about 1.5 hours, under the powertrain warranty. After the work in January the pump has sounded normal except for an occasional chirp.

Chas.

 

Up here in Canada, getting the TSB acknowledged was difficult - and the pump is BO until forever.

Solved the problem - changed to the 2010 Prius - after living for 6+ months with the squeaky pump on the 2006.

 

Mine makes a squeaky sound when the engine stops sometimes, but I hear it near the pass side. If the coolant pump is on the driver side, what the heck am I hearing???

 

You are probably hearing the serpentine drive belt squeaking. The belt becomes glossy after 50K miles, and may start to slip on the pulleys. The remedy would be to replace that belt.

 

How would it make that noise after the engine has stopped at a red light?

 

If the noise is being made after the engine has stopped, then it would not be coming from the serpentine drive belt. You would then need to look for an electric pump or motor as the source of the noise, such as the brake actuator pump mounted on the firewall. To confirm whether the brake actuator pump is the problem, repeatedly pump the brake pedal when the car is READY, to force the pump to run.

If the noise is made as the engine is stopping (which is the meaning that I obtained from your previous post #109) then it could be the belt slipping.

 

Thsnks. I guess I just miss worded it. I'll give the brakes a try.

 

Thanks for the warning. My dealer overfilled the oil and underfilled the coolant. I just love bringing the car back for needless work, especially after I took the time to warn them and print out copies of the relevent posts. ARRRRRRG!

 

I have a 2005 pruis and have been trying to get Toyota to fix the squeaking water pump for 2 years. It was under warranty when I first complainted I gone to 2 different dealers 4 times, call Toyota hot line, wrote to president of Toyota. The problem is intermittent but it exactly like the TB discribes. I even made a recording of the squeaking. Toyota dealers tell me if them can't hear it they won't fix it.
I like my prius and think it's a very good car, but Toyota customer service is offal.
For my next car I hope to have more choices when I buy a green car. Maybe the Nissan Leaf. I put a solar system on my roof and am producing 30% more electricity that I am using.
Any suggestion on how I can get Toyota to honor its warranty??
[email protected]

 

My '05 is in the shop right now for a inverter cooling pump replacement (that was scary yesterday when it failed - I made it to the dealer after a harrowing drive down I-95 for several miles with the engine surging intermittently). They told me the pump was nationally backordered and it would be at least a week. I also told them about the squealing noise up front after shutdown that has been occuring since maybe winter of '07/'08. The service rep said nothing of this TSB. Looks like I'll have to print it out and demand replacement. The squealing that occurs immediately after engine shutdown has become exceptionally loud in cool weather - my wife says it sounds like a wounded dog.

 

I'm too late?

I have over 60k on the car now; I think that makes it too late for me to have it done by the dealer through the TSB? After my run in with a dog Monday morning, it sounds like there are steel balls in a garbage disposal when you turn the car off. NASTY! I'm sure the dealer will say it's damage from the dog hit.
It was a very large German Sheperd dog. Looks more like a deer hit!

 

I feel your pain, but don't know how you can get Toyota to do the right thing as I had trouble with that myself with my '05's dreaded coolant flow valve noise since '07. They gave the same run around, nothing but "not my problem" responses and/or form letter thanking me for contacting Toyota (Dear Toyota customer service, stop thanking me just fix the problem!) Thanks to this forum I was able to show my local mechanic the valve location (see attached if anyone needs it) and they repaired it quick and easy for parts (~$40) + labor, money I'm glad to give them instead of slimy Bay Ridge Toyota in Brooklyn NY.

 

Sigh.

I listened to the recordings and had heard that noise, pretty much from day one.

I asked the dealer about it in 2004, and was informed that it was 'normal.' I been reading this forum back then, but somehow missed the threads about this problem.

For about the last six months, I've had a check engine light and one of the DTC P112{0123} codes. I'm pretty sure it was the P1121 code and was planning to replace the associated valve.

However, the check engine light didn't come on until the noise stopped. (E.g., I don't think that the pump is pumping.)

I'll do the work myself, but am wondering if I have to replace both the pump and the valve, or is it more likely just the pump?

 

OK I have the noise in my 2009 Prius. Do I follow the instructions above?
Please be kind I'm a 72 year old "Nana"