Car overheating (09 Corolla), replaced thermostat with no luck

[BrunoPuntzJones]

Kinda scratching my head.

09 Corolla with 320k miles.

Wouldn't blow warm air and was overheating so replaced the thermostat (with Toyota part) and coolant.

Worked fine for a couple of days and now back to the same problem.

Gauge looks to go wild. Will rise to the red line slowly, then drop some, then climb, then drop half-way, etc. Squirrelly.

Was thinking maybe air in the cooling system but think it's been purged pretty well, and don't think that would explain the lack of hot air.

My OBDII reader is just throwing E so I guess it's toast and will go to vatozone or something tomorrow and get the code checked out (was getting P301, bad ignition coil which I replaced and the CEL went away for a bit...).

I'm not leaking coolant, and no white smoke, so don't think it's a head gasket or cracked head.

Was about to head to bed but figured I'd throw it out to you folks for ideas.

 

[Gerle]

Does the cooling fan spin, is your waterpump working?

 

[jlee]

Was thinking maybe air in the cooling system but think it's been purged pretty well, and don't think that would explain the lack of hot air.

You think it has or you're sure it has? An air bubble preventing coolant from circulating through the heater core could certainly cause what you're seeing.

If you bled the coolant, did you do it with the heat on full hot?

 

[boomerang]

Pull your dipstick and check for coolant in the oil. The temperature gage swinging like that is typical of a low coolant situation. Keep in mind that the problem existed prior to replacing the thermostat. IMO your coolant level was low prior to that work being performed. You may have not purged all the air out of the system after the thermostat replacement but the problem existed prior. The coolant is going somewhere. You have eliminated the ground and the tailpipe.

There's only one place left unless there is an antifreeze thief working your neighborhood. /s

 

[pcgeek11]

Agree with the low coolant and trapped air in the system. That is what is causing the temp gauge to swing between hot and cool. It is designed to read in the liquid, when an air pocket forms around it the temp will drop. If it was just the water pump it would read hot all the time. It could also be a combination of the water pump ( worn out at 320K Miles ) and air in the system.

 

[jlee]

Agree with the low coolant and trapped air in the system. That is what is causing the temp gauge to swing between hot and cool. It is designed to read in the liquid, when an air pocket forms around it the temp will drop. If it was just the water pump it would read hot all the time. It could also be a combination of the water pump ( worn out at 320K Miles ) and air in the system.

Water pumps are designed to leak when they fail. It may be worth looking closely at the bottom of the water pump to make sure it's not leaking onto an underbody panel and then evaporating. That could potentially explain coolant loss before complete and catastrophic water pump failure.

 

[NutBucket]

I also agree there's air in the system. There's usually a bleed screw at the highest point in the system...which isn't necessary the radiator cap.

 

[Zorba]

How is the condition of the old coolant? I had very similar issues on a '91 Grand Marque. The radiator was completely full of sledge. I replaced the radiator and all the issues went away.

Other than the radiator, I'd look at the water pump. You can make sure it is flowing by feeling the upper radiator hose after the thermostat opens. If you squeeze it you should feel flow, or you can usually see flow coming in if you leave off the radiator cap.

Did you test the old thermostat? Or the new one before it was installed? If you still have the old one, put in a pot of water and see what temperature it opens at, if at all. If it doesn't open, good chance that was the issue and the new one is dead too. If it opens, then it wasn't your problem.

 

[jlee]

How is the condition of the old coolant? I had very similar issues on a '91 Grand Marque. The radiator was completely full of sledge. I replaced the radiator and all the issues went away.

Other than the radiator, I'd look at the water pump. You can make sure it is flowing by feeling the upper radiator hose after the thermostat opens. If you squeeze it you should feel flow, or you can usually see flow coming in if you leave off the radiator cap.

Did you test the old thermostat? Or the new one before it was installed? If you still have the old one, put in a pot of water and see what temperature it opens at, if at all. If it doesn't open, good chance that was the issue and the new one is dead too. If it opens, then it wasn't your problem.

If the water pump wasn't working, the car would legitimately overheat very quickly and he'd have an obvious problem.

 

[Raizinman]

I once had a Toyota that I had a difficult time getting all the air out of the cooling system. I jacked up the front end (car ramps might work too) about 24 inches so the radiator would be the highest point for air to bleed. I started the car to let it heat up about 3 or 4 times and 'poof' the air was gone and it was functioning just fine. The symptoms you described are a cooling system with air in it. The higher you can get the front end, the quicker the air will bleed.

 

[Rifter]

air in the cooling system.

 

[dave_the_nerd]

I'm going to buck conventional wisdom and suggest that your car may be being eaten by termites.

 

[NutBucket]

I once had a Toyota that I had a difficult time getting all the air out of the cooling system. I jacked up the front end (car ramps might work too) about 24 inches so the radiator would be the highest point for air to bleed. I started the car to let it heat up about 3 or 4 times and 'poof' the air was gone and it was functioning just fine. The symptoms you described are a cooling system with air in it. The higher you can get the front end, the quicker the air will bleed.

Yes, but there's also a bleed screw at the high point of the system...unless Toyota is that daft.

 

[RLGL]

time for a leak down test

 

[BrunoPuntzJones]

Hey sorry for the delayed reply.

So bled the system again, for like 20 minutes...Kept adding water and still bubbles. Thought I had it cleared up but overheated again yesterday. Got home and popped the hood and low coolant.

Part of the story I forgot to tell was I've been getting an engine misfire code. I changed the plugs a couple of weeks ago and tried a new ignition coil with no luck. Was thinking two different problems.

Guess you can predict what my next thought was...fuuuuuuu....

Slow head gasket leak. Exhaust and oil were fine. Don't have the tools for a compression check and since the car was only $550 I bought a can of this:

https://www.amazon.com/Bars-Leaks-1111-Head-Gasket/dp/B0036VRQ70/ref=cm_cr_arp_d_product_top?ie=UTF8

$23 at Wal-Mart. I have NEVER bought any of these fix in a can products. But I figured on a $550 car, why not?

Dumped half a bottle in the radiator, ran it for 20 minutes with heat on full. Let the car sit and then topped off the radiator and coolant tank.

Drove the car five times today and it's started up without any hesitation (used to have just a slight shudder when starting). No loss of coolant and the fourth time I started it up the CEL went off.

Can't believe one of the miracle in a bottle things worked. I'd never use it in a car I was going to keep or was worth more than a few grand, but I'm tickled so far.

No idea how long it will last but it will be enough to buy me some time to find a replacement. Whew.

 

[mindless1]

A compression test gauge can be had for *free* (with deposit) as a loaner tool from Advance Auto, Autozone, maybe others. I like to get one and do the test even if the vehicle runs fine, when the spark plugs are done since it is such a large interval these days with platinum or iridium plugs.

As far as the leak, since it's going out the exhaust apparently, it could be better or worse than a head gasket leak, could be cracked head, warped head, or just an intake manifold gasket which drifts towards DIY in a day territory even for someone who has never done that before, if you have basic hand tools.

If you had done a compression test before putting the stop leak goop in, that would have given you a better idea if intake or head, though I suppose it's fixed as long as it keeps enough coolant between whatever interval you check and top it off, except that can foul the catalytic converter and oxygen sensors eventually.

 

[RLGL]

Compression testing is a waste of time for diagnostics. I have seen engines with normal compression and yet have cracked heads, cylinders and pistons.
Compression testing is a relative means to see if the wear in an engine is even. There are too many variable to the test that will affect its outcome.

 

[mindless1]

^ You are incorrect. Some odd cases where it didn't find a problem, are not a reason not to get an estimate of this aspect of engine health, and it can find problems. It is a simple test that people can do at home for FREE with a loaner tool, and while the plugs are pulled they can be inspected, which might also indicate coolant getting into a cylinder.

Further if the wear is even but all are getting low, it may not be worth pursing a problem much deeper (down) than a head gasket, may be time to swap the engine or offload the car on some poor sap "as is". Granted it could be valve deposits, but so it goes with an aging vehicle, you may have one primary problem and some others you have to assess when it comes time to decide what to do.

It has 320K mi. An overall assessment of cost to keep it running is something to think about at this point.

 

[RLGL]

^ You are incorrect. Some odd cases where it didn't find a problem,

You are WRONG! I spent 40 years diagnosing and repairing engines, a compression test is a waste of time in most instances.
At 320K it is time to get an ACCURATE assessment of the issues. A leak down test can lead to a better idea as to what is wrong . A tear down may also be needed to further asses the final diagnosis. Most likely the vehicle should be considered for replacement

 

[mindless1]

null post

 

[mindless1]

I edited this post because RLGL was going to blow a gasket from what I frankly replied.

I don't care about winning an argument on an internet forum and social graces prevent me from leaving what I had posted, which was already conservative IMO.

Long story short, do the cheap things you can DIY before throwing a lot of money at a vehicle with 320K mi.

 

[eng2d2]

Hey sorry for the delayed reply.

So bled the system again, for like 20 minutes...Kept adding water and still bubbles. Thought I had it cleared up but overheated again yesterday. Got home and popped the hood and low coolant.

Part of the story I forgot to tell was I've been getting an engine misfire code. I changed the plugs a couple of weeks ago and tried a new ignition coil with no luck. Was thinking two different problems.

Guess you can predict what my next thought was...fuuuuuuu....

Slow head gasket leak. Exhaust and oil were fine. Don't have the tools for a compression check and since the car was only $550 I bought a can of this:

https://www.amazon.com/Bars-Leaks-1111-Head-Gasket/dp/B0036VRQ70/ref=cm_cr_arp_d_product_top?ie=UTF8

$23 at Wal-Mart. I have NEVER bought any of these fix in a can products. But I figured on a $550 car, why not?

Dumped half a bottle in the radiator, ran it for 20 minutes with heat on full. Let the car sit and then topped off the radiator and coolant tank.

Drove the car five times today and it's started up without any hesitation (used to have just a slight shudder when starting). No loss of coolant and the fourth time I started it up the CEL went off.

Can't believe one of the miracle in a bottle things worked. I'd never use it in a car I was going to keep or was worth more than a few grand, but I'm tickled so far.

No idea how long it will last but it will be enough to buy me some time to find a replacement. Whew.

Damn I wish I did this on my 200k miles car instead of selling it. Good to know and next time,

 

[jlee]

Compression testing is a waste of time for diagnostics. I have seen engines with normal compression and yet have cracked heads, cylinders and pistons.
Compression testing is a relative means to see if the wear in an engine is even. There are too many variable to the test that will affect its outcome.

Have you seen an engine show lower compression than specified by the manufacturer and yet be perfectly healthy?

I'm guessing not, because otherwise the manufacturer wouldn't have a specification.

You are WRONG! I spent 40 years diagnosing and repairing engines, a compression test is a waste of time in most instances.
At 320K it is time to get an ACCURATE assessment of the issues. A leak down test can lead to a better idea as to what is wrong . A tear down may also be needed to further asses the final diagnosis. Most likely the vehicle should be considered for replacement

You're a funny guy.

Compression? 190/190/104/190. I don't care how much experience you have - a compression test can be useful. Sure, leakdown is better...but compression tests are quick and easy and will often highlight a glaring issue.