Heater blowing cold air in front but back is fine (2017 CX-9)

[megaman123]

Update: I made sure heat was off, remoted started and left it, which is 10 or 15 minutes. Checked the hoses ands temps were 40 C (104 F) for inlet and 37.7 C (100 F) for outlet. Takes a little bit of time for my meat thermometer to climb up to the temp so I have to leave it for about 90 seconds on each hose. When I re-did the inlet after doing the outlet, it came in at 37.9 C. So based on that diagnosis, seems like the heater core is not plugged.

But, as you can see in the pic, more coolant just dropped out after letting the car run. So that means it's defnitely dumping more coolant when car is running. Just don't know where it's coming from. There's no fresh fluid seen on the tray under the rad. I'd guess it's further up towards the cabin by 6-12 inches.

 

[edmaz]

Update: I made sure heat was off, remoted started and left it, which is 10 or 15 minutes. Checked the hoses ands temps were 40 C (104 F) for inlet and 37.7 C (100 F) for outlet. Takes a little bit of time for my meat thermometer to climb up to the temp so I have to leave it for about 90 seconds on each hose. When I re-did the inlet after doing the outlet, it came in at 37.9 C. So based on that diagnosis, seems like the heater core is not plugged.

But, as you can see in the pic, more coolant just dropped out after letting the car run. So that means it's defnitely dumping more coolant when car is running. Just don't know where it's coming from. There's no fresh fluid seen on the tray under the rad. I'd guess it's further up towards the cabin by 6-12 inches.

Very sorry to say, but that looks bad. No warranty left I presume?

 

[Jack Rabbit]

Update: I made sure heat was off, remoted started and left it, which is 10 or 15 minutes. Checked the hoses ands temps were 40 C (104 F) for inlet and 37.7 C (100 F) for outlet. Takes a little bit of time for my meat thermometer to climb up to the temp so I have to leave it for about 90 seconds on each hose. When I re-did the inlet after doing the outlet, it came in at 37.9 C. So based on that diagnosis, seems like the heater core is not plugged.

But, as you can see in the pic, more coolant just dropped out after letting the car run. So that means it's defnitely dumping more coolant when car is running. Just don't know where it's coming from. There's no fresh fluid seen on the tray under the rad. I'd guess it's further up towards the cabin by 6-12 inches.

1st thing to do is make sure its not also getting into your engine. Do an oil change, check the oil and also send a sample in for UOA analysis. Hopefully it's just an external leak. Then try to locate the leak. If you cant find it, just get it into your mechanic at this point.

 

[megaman123]

Okay, I don't know WTF is going on now. I just went to start it to reposition in my driveway and the car won't start. Not remotely either. It's been 48 hours since I drove it but I did remote start it and let it run till it shut off this morning.

No lights inside or out were left on. I have been looking at the actuators within the past hour and had the heat and fans going without actually starting the car. But the total time for that can't be more than 7 minutes max. over a few times I was trying this. Okay, MAYBE 10 minutes at most, but really doesn't feel like that.

Maybe I drained the battery. Who the eff knows at this point. The effed up thing is that my wife and the kids went to her parents with the 2009 Accord, which didn't start Saturday morning. But that battery is 5 years old and Friday was the only brutally cold day of the winter so far. I did test it a few weeks ago with my multimeter and it was showing 12.5V. I boosted it Saturday morning, but I gave her that booster, plus the charger I also have, along with the 100 foot outdoor cord just in case. At least they'll be home soon. I hope it's just the battery.

 

[Jack Rabbit]

Okay, I don't know WTF is going on now. I just went to start it to reposition in my driveway and the car won't start. Not remotely either. It's been 48 hours since I drove it but I did remote start it and let it run till it shut off this morning.

No lights inside or out were left on. I have been looking at the actuators within the past hour and had the heat and fans going without actually starting the car. But the total time for that can't be more than 7 minutes max. over a few times I was trying this. Okay, MAYBE 10 minutes at most, but really doesn't feel like that.

Maybe I drained the battery. Who the eff knows at this point. The effed up thing is that my wife and the kids went to her parents with the 2009 Accord, which didn't start Saturday morning. But that battery is 5 years old and Friday was the only brutally cold day of the winter so far. I did test it a few weeks ago with my multimeter and it was showing 12.5V. I boosted it Saturday morning, but I gave her that booster, plus the charger I also have, along with the 100 foot outdoor cord just in case. At least they'll be home soon. I hope it's just the battery.

Okay, I don't know WTF is going on now. I just went to start it to reposition in my driveway and the car won't start. Not remotely either. It's been 48 hours since I drove it but I did remote start it and let it run till it shut off this morning.

No lights inside or out were left on. I have been looking at the actuators within the past hour and had the heat and fans going without actually starting the car. But the total time for that can't be more than 7 minutes max. over a few times I was trying this. Okay, MAYBE 10 minutes at most, but really doesn't feel like that.

Maybe I drained the battery. Who the eff knows at this point. The effed up thing is that my wife and the kids went to her parents with the 2009 Accord, which didn't start Saturday morning. But that battery is 5 years old and Friday was the only brutally cold day of the winter so far. I did test it a few weeks ago with my multimeter and it was showing 12.5V. I boosted it Saturday morning, but I gave her that booster, plus the charger I also have, along with the 100 foot outdoor cord just in case. At least they'll be home soon. I hope it's just the battery.

It might be the battery.

But, did you check the coolant level before starting it? At this point and leaking the fluid your leaking, you really should be in/near the vehicle and watching the thermostat until you get it to the mechanic.

 

[megaman123]

It might be the battery.

But, did you check the coolant level before starting it? At this point and leaking the fluid your leaking, you really should be in/near the vehicle and watching the thermostat until you get it to the mechanic.

Yeah, I checked the coolant level after remote starting this morning. Basically the same as on Sunday, two inches below F. The last pic I took of that cardboard is after that remote start. So a little bit more came out then. And I did check it like 3 hours after that and it was the same. It leaks basically when the car is running. I just checked the cardboard now, after running the heat (without starting car) a few times in the past hour while looking at the actuators and there's no new drops of coolant.

And yeah, definitely going to mechanic due to that leak. I'm wondering if it's leaking at the thermostat housing. Don't know where it is on this vehicle but I saw that on a YT video from some other car.

Now I have to decide if I go to the dealer, which will probably cost more, or other mechanic. The dealer mechanics might have more expertise with these vehicles due to volume, but doesn't mean they are better mechanics. Regardless, I'm going to summarize everything we've discussed here in bullet point form to make things easier for them.

Very recently I got the oil changed at Honda dealer for my Accord and they told me all my pads were at 2mm and said I should change those and machine all rotors. I had new pads, calipers and rotors done only 29k kms/18k miles ago done on the rear. Advisor even showed me on the brake display piece on the counter. And it's printed on the second page of invoice. I called a few days later and asked a different advisor to double check what they found and they said the same thing. I went to a mechanic I'd never been to before and he said I'm an honest guy. I'll hoist it and tell you. He said 5-6mm in the back and fronts are at 4. I thanked him and said I'll come back to you when the fronts go. So, I am thinking perhaps I go to him. He has great reviews.

The local mechanic I trusted the most ran a chain shop. He just oozed professionalism and kindness. But one day I pass by and it's owned by someone else. I went to that guy a couple times and yeah, that was a mistake. The other one 20 minutes away where I used to live retired.

Would you guys go to dealer in this situation or any reputable mechanic?

EDIT: edmaz mentioned earlier about the cracked cylinder head problem, which could result in engine replacement. That means I'll have to bring to dealer. Because if it comes to that, I'll need them to try and get some goodwill out of Mazda.

And having discovered this leak, does it seem most likely that my weird delayed heat is due to something caused by that leak? Like I can rule out the actuators?

 

[megaman123]

When the actuators are operating you will see the levers and linkages move. Those parts are external and visible. Keep the fan on low and you may be able to hear them as well.

Look at this picture, it's an ebay listing for a Mazda CX9 hvac box. It may not be identical given that it could be from an earlier year but should be similar to yours. You can see two actuators in the middle and one off to the left. I'm not sure exactly which is which but perhaps the one off on it's own to the left regulates the temperature. When changing settings for direction and temperature you should be able to figure out which is which.

I see what you're saying now. I popped open the glove box and I see two actuators there on the left. The top one uses that white lever to the bottom left. That moves around when I change fan directions. For the one below it, I can't see it moving anything.

Above the cabin air filter (number 3) is the blend door for the air circulation setting. That door opens and shuts.

The gears that are visible close to the actuators don't move. But I have no idea if they are related to the actuators. That's the case for the one beside the actuator by the glove box and the case for the one close to the gas pedal, which is the last pic.

 

[megaman123]

Very sorry to say, but that looks bad. No warranty left I presume?

Yeah, no warranty.

 

[Jack Rabbit]

Yeah, I checked the coolant level after remote starting this morning. Basically the same as on Sunday, two inches below F. The last pic I took of that cardboard is after that remote start. So a little bit more came out then. And I did check it like 3 hours after that and it was the same. It leaks basically when the car is running. I just checked the cardboard now, after running the heat (without starting car) a few times in the past hour while looking at the actuators and there's no new drops of coolant.

And yeah, definitely going to mechanic due to that leak. I'm wondering if it's leaking at the thermostat housing. Don't know where it is on this vehicle but I saw that on a YT video from some other car.

Now I have to decide if I go to the dealer, which will probably cost more, or other mechanic. The dealer mechanics might have more expertise with these vehicles due to volume, but doesn't mean they are better mechanics. Regardless, I'm going to summarize everything we've discussed here in bullet point form to make things easier for them.

Very recently I got the oil changed at Honda dealer for my Accord and they told me all my pads were at 2mm and said I should change those and machine all rotors. I had new pads, calipers and rotors done only 29k kms/18k miles ago done on the rear. Advisor even showed me on the brake display piece on the counter. And it's printed on the second page of invoice. I called a few days later and asked a different advisor to double check what they found and they said the same thing. I went to a mechanic I'd never been to before and he said I'm an honest guy. I'll hoist it and tell you. He said 5-6mm in the back and fronts are at 4. I thanked him and said I'll come back to you when the fronts go. So, I am thinking perhaps I go to him. He has great reviews.

The local mechanic I trusted the most ran a chain shop. He just oozed professionalism and kindness. But one day I pass by and it's owned by someone else. I went to that guy a couple times and yeah, that was a mistake. The other one 20 minutes away where I used to live retired.

Would you guys go to dealer in this situation or any reputable mechanic?

And having discovered this leak, does it seem most likely that my weird delayed heat is due to something caused by that leak? Like I can rule out the actuators?

I've always had a good local mechanic for the stuff I can't DIY or dont have time to...he'll fix what he can and refer me elsewhere if needed. If your guy wil take a look at it for no charged/minimal charged like $20/$30 then I'd start there. Can always got to the dealer for more complex work

 

[megaman123]

I really don't even like to mention this, but there's a well-known, systemic cracking issue with the cylinder head on a number of Skyactiv Turbo model years, including yours. And (again not happy to say) what you described above sounds a lot like the air self-purging process that these vehicles automatically do. Of course, I certainly hope that's not the issue with your vehicle, and that it actually turns out to be a much less severe and less costly repair!

Thanks.

I really do hope this is not the problem. Doing some googling on this I see people have needed engine replacement for that. Which means I'm going to have to bring it to dealer instead of other mechanic.

Now I have to wonder if I should drive the 15 minutes to the dealer or get a free tow using my CAA. Probably get the tow.

My car has 76k kms/47k miles on it.

 

[megaman123]

And here is the TSB regarding the thing edmaz was talking about. Coolant leaks at cylinder head. And I see there are other topics on the forum about this.

https://static.nhtsa.gov/odi/tsbs/2022/MC-10215280-0001.pdf

 

[edmaz]

If you take your no-warranty vehicle to a dealership, they're almost certainly going to hit you up for a non-refundable diagnostic fee, regardless of what the issue is. Here's one thing for you to consider doing, in order to possibly prevent that from happening.

Based on what you've written so far, it sounds to me that you're handy and capable enough to try examining the area that's typically where the damage to the cylinder head occurs. The common place for heads cracking and leaking coolant on the Turbo, is where the exhaust manifold is attached, down low where the head meets the block.

If you're able to examine the exhaust manifold area from the sides, perhaps you'll see some sign of wetness from coolant leaking. Or another possibility would be to have your indy shop hoist it up, and take a look up at that area from underneath the vehicle.

The idea behind this is to be able to take the vehicle into the dealership, and simply state that it has a cracked head, without even requesting them to diagnose it. In fact, you could even just go ahead and do that without finding a leak on the backside at all. They've probably seen more than a couple of cracked Turbo heads by now, and may very well just accept what you're saying.

The second part of your conversation with them would be to ask how much goodwill they would provide to you for a cylinder head replacement. This cracked Turbo cylinder head is certainly in the systemic category, and I suspect there already are lawyers busily typing up the class action suits on this. At this point in the game, Mazda might very well be willing to pick up quite a bit of these non-warranty repair bills, just to try keeping the wolves at bay.

If they push back and say they want to diagnose the issue, you could just increase the pot with another bluff, and say you already have confirmed the head is cracked. Depending on how good a poker player you are, they might just cave and accept your story. And if that happens, you get to find out what (if anything) they would be willing to do for you, if in fact the head is cracked, without having to pay any diagnostic fee up front.

 

[Jack Rabbit]

@edmaz had great advice and like @edmaz said see if they'll goodwill or least supply the part's at cost. Thats your best option.

For older vehicles, the game plan has always been just go to salvage-yard and get a used engine for $500 and pay someone $300-$500 to throw in. My Fords and Toyotas engines outlasted their frames but i've helped friends/relatives buy and/or put in used salvage engines for under $1000.

However in this case it's not practical as its mazda defective engine heads. The mazda used engines are rare(as mazda aren't mass sold like Ford, Toyota, etc) and still cost several thousand dollars($5000 to $7000) and you could still end up with another cracked head.

Only options are to see if mazda will goodwill fix or pick up part of the tab for head replacement.

Or pay full price for a new head replacement( or maybe even a new engine), if your planning on keeping the vehicle several more years.

As i've been waiting for my head to crack, alternative options that I've researched include ...

Second alternative, get some experience welder to low heat aluminum weld the head if it's a repairable spot. This is preferable repair if not replacing the head but it could turn out worse depending on if the welder isn't good or careful. But the heads scrap anyway.

Lastly, just get a couple tubes of epoxy-weld (aluminum) and DIY the head yourself. (Fyi: JB steel weld might withstand higher temps but aluminum weld more closely match head so choices to make). Cost you under $50 for the metal epoxy plus cost of new gaskets, seals, new bolts, materials, etc. and maybe labor cost if have a garage do it. Saw this online and the epoxy-weld patches appeared to hold well.
Might as well, heads just getting thrown out anyway. Can't possibly screw it up any worse.

 

[megaman123]

Well, can't find any cracks where the cynlinder head meets the engine or around the exhaust manifold or wherever. And I used a mirror to look on the backside but only a small spot in accessible. And no fresh leaks on any hoses that I can see though I've not driven it for 72 hours now. I suppose if I jacked it up myself it might help to get a better idea of where it's dropping down from. Things are just so compact.

I pulled the dipstick and oil looks normal to me and not milky but can't say for sure some coolant didn't mix in there without getting analysis done.

If I go to an independent mechanic to hoist, he is going to charge me for that. My cousin's friend back 10 years ago would have done that for me. And he worked at a Honda dealer and actually did after hour work for me at the dealer for cash. But he doesn't live around here anymore.

Tomorrow I'll be speaking to dealer. However, I should mention, I bought this used from an Audi dealer. I just happen to get this serviced at the local Mazda but I'm hoping they can do something for me.

 

[megaman123]

Spoke to service manager at local Mazda. He said almost no chance Mazda covers this past warranty. And he says he doesn't have much of a leg to stand on due to me buying this used at an Audi dealer and only having done one oil change and tire change at them. My last oil change was done at the local chain mechanic close to me as I had to drive a few hours for a trip and the timing didn't work out otherwise I would have done it with them. Point being, he can't say he's observed this car multiple times.

By the way, the powertrain warranty expired Dec. 7/22. I'm at 76k kms/47k miles.

They would do $149 CAD diagnostic. And he says my weird heat problem probably stems from the leaking coolant but who knows.

He then suggested I call Mazda Canada customer service and go from there. And they'd want a dealer to do a diagnosis of course.

 

[edmaz]

Spoke to service manager at local Mazda. He said almost no chance Mazda covers this past warranty. ....

Certainly not what you wanted to hear, but at least he was honest about it and didn't try to jerk you around with a bunch of mumbo jumbo.

Even though this sounds like another cracked head, IMO you need to confirm that before making any decision, simply because it still could be some lesser issue.

 

[megaman123]

Dealer said crack in the sonar head gasket. Averages $5-6k CAD repair. He said by eyeing the oil it didn't seem contaminated and based on what he sees, it's external.

I've now reached out to Mazda Canada and they said they will obtain the report from the dealer and get back to me within 72 hours.

 

[edmaz]

Hopefully Corporate will decide to provide significant help for you on this. If not, you might want to find out if any class action lawsuits against Mazda have been filled for this issue in your province. Most of these cylinder head repairs so far have been done under warranty, with not much publicity. However, now we're beginning to see more cases such as yours, where it's happening to vehicles out of warranty.

This is a systemic and fairly widespread issue, and Mazda has basically admitted to that in print. Franky, I don't think it would take very much pressure to make Mazda buckle on this, and provide full extended warranty coverage for these turbo head replacements. The deck is stacked against Mazda on this, and a smart move for them would be to completely eliminate the cost of lawsuits, by simply just doing the right thing, before the legal eagles have a chance to sharpen up their blades.

And if you get no traction in communicating with Mazda on this, you might want to mention the possibility of you taking the legal route. Just that alone might very well cause them to start singing a different tune.

 

[megaman123]

It look 19 days and multiple follow ups to get an answer and Mazda said they can't help me as I'm past my powertrain warranty. I was 2 months past when I brought it into the dealer. Problem started a couple weeks before that. They spoke to the dealer and then their internal technical specialist.

If I had known about this issue popping up on CX-9s of this generation then I probably would not have gotten it. I test drove two of these and a Highlander. This was more in my budget but that just backfired. But I did like how it drove more like a car while the Highlander was like a truck. It felt and looked sportier and had the better interior.

The more you read about any vehicles interested in then there's a possibility you talk yourself out of any car, but I wish I had noticed this issue. No guarantee any other car wouldn't have had a problem but obviously I regret it now. Drove a 2006 Ford Fusion from new to 217,000 kms in 15 years before the water pump broke and I realized the fix was more than the value of the car so I scrapped it. But no major repairs the whole time. That's when I went with the CX-9. Oops...

 

[rowlands57]

I am sorry to hear that there will be no help coming from Mazda on this. It does really hit hard when you buy what should be a reliable vehicle and have something like this happen. The only hope is that there will be a class action against them that may lead to some benefit to you down the road. Keep all the paperwork in the event that does happen and you have to file a claim.

I had a very similar issue with my 2016 Audi A3. At 104K miles cylinder 4 just lost all compression. Far out of the warranty and still in too good a condition to scrap so I had to pony up for a used engine. Thankfully the shop I have used for years found an engine with 24K miles. I'll never get my money's worth out of the car but I had little choice really. I just will avoid the Audi brand from here on out.