[OstarDimen]

Hello guys, 2017 Subaru Impreza owner here, glad to be in this forum.

I'll get right to it, was driving home from work today and I am about five minutes into my drive and my car started riding rough, look in the rear view and all I see is white smoke. The car has had routine maintenance done and nothing extra. Has about 67K miles on it.

Hit me with your best guesses so I know what to start looking at. The Head gasket is already on the list, but want more input. It's looking like regardless I'll be towing this damn car to Subaru....for yet ANOTHER trip to the service department.

 

[Sam2017Impreza]

White smoke is normally a head gasket letting go or coolant in the combustion chamber. Blue smoke is oil in the combustion chamber. I hate to say it but I think you'll need a head gasket replacement. Let us know if it ends up being anything else.

 

[Boinks]

White smoke is normally a head gasket letting go or coolant in the combustion chamber. Blue smoke is oil in the combustion chamber. I hate to say it but I think you'll need a head gasket replacement. Let us know if it ends up being anything else.

Congratulations! You're officially a Subaru owner

 

[BruceP]

Question: Has there been regular checks of the underhood fluids?

Specifically, you should be opening your hood and checking the antifreeze level in the reservoir tomorrow morning (COLD ENGINE!!)

If it needs fluid... DISTILLED WATER is better than nothing. ASIAN BLUE antifreeze is preferred.

Also, with ANY vehicle, It is IMPERITIVE to check the underhood fluids at least weekly. Expect antifreeze to evaporate and need replenished.

 

[Alex_Rochester]

White smoke means you are burning coolant. Either a blown gasket, or a cracked head.

 

[OstarDimen]

It's the head gasket, they are fixing it right now

 

[BruceP]

It's the head gasket, they are fixing it right now

Do you know if they are changing BOTH or just a single head-gasket?

Did they offer any explanation WHY it failed?

 

[Sam2017Impreza]

Do you know if they are changing BOTH or just a single head-gasket?

Did they offer any explanation WHY it failed?

I think it being a Subaru is good enough of an explanation as to why it failed lol

 

[Sam2017Impreza]

Congratulations! You're officially a Subaru owner

Lol Yes that's all I every wanted

 

[BruceP]

I think it being a Subaru is good enough of an explanation as to why it failed lol

that is kinda unfair to Subaru. I have owned Honda cars which blew antifreeze out of the tailpipe due to head-gasket.
In other words... this can happen to ANY engine. (espcially if antifreeze level is allowed to run low.)

 

[peaty]

that is kinda unfair to Subaru. I have owned Honda cars which blew antifreeze out of the tailpipe due to head-gasket.
In other words... this can happen to ANY engine. (especially if antifreeze level is allowed to run low.)

Sucks that it happened and glad you are getting it fixed. I'd be curious to know why it happened too. It has not been a major issue for years.

 

[JGR]

Congratulations! You're officially a Subaru owner

Blown head gaskets haven't been a common problem with Subaru engines since before 2009. Most failures were on the SOHC EJ25. In 2009 Subaru replaced their previous coolant (green) with Subaru Super Coolant (blue), which was apparently part of the fix.

Subaru Head Gasket Problems (Years and Models Affected)

Thinking about buying an old Subaru? They're great cars, but a head gasket leak could quickly turn your thrifty daily driver into a money pit.

oards.com

 

[Sam2017Impreza]

Sucks that it happened and glad you are getting it fixed. I'd be curious to know why it happened too. It has not been a major issue for years.

I'm wondering if it has anything to do with the coolant running low. I know on my wife's 3.6 outback and my Impreza I have to check the coolant level on the tank every few weeks. I check it while the engine is up to temp but I've heard from other people to check it when the engine is cold.

 

[peaty]

I'm wondering if it has anything to do with the coolant running low. I know on my wife's 3.6 outback and my Impreza I have to check the coolant level on the tank every few weeks. I check it while the engine is up to temp but I've heard from other people to check it when the engine is cold.

I'm curious how you check when it's up to temp? Are you just looking in the overflow tank at the level? Since you shouldn't remove the cap when it's up to temperature, that's dangerous unless you have a cap that has a lever and you can release the pressure. The OEM caps don't typically have the pressure release lever and are at they are at about 15.5 PSIG at operating temperature. If you open the cap then the coolant will flash boil and spew out hot coolant and steam.

It's okay to look at the overflow when hot but if you check inside the radiator when the motor is cold; that lets you know the cap is operating properly. It should be sucking coolant back into the radiator as it cools and creates a vacuum.

If you are adding coolant on a regulars basis it would be a good idea to have the radiator cap pressure tested or if it's old just replace it. I replace my caps every so often. I just replaced the cap on our 2013 Outback, they are pretty cheap >> Link<< If it's not holding enough pressure that will slowly boil off coolant. Since it will lower the boiling point of the coolant. If it's doing the opposite, it wont's boil off coolant but hold too much pressure; that can pop a hose or radiator itself. This is why I changed mine, just cheap insurance.

One watch out is be sure the hose that goes from the radiator cap area to the overflow tank is tight. Once I replaced a radiator thinking it was leaking at the upper tank crimp. I saw fluid at the seam figured it was time since the car was 15 years old. Plastic tanks end up needing to be replace at about 10 -15 years. (not a Subaru thing a plastic tank aging thing) It ended up being a loose overflow hose. After I replaced the tank, I saw where it was coming from and put a hose clamp on it which fixed the problem. I need a new radiator and hoses anyway, when your plastic radiator gets old it's not an if but a when it will fail.

 

[Sam2017Impreza]

I'm curious how you check when it's up to temp? Are you just looking in the overflow tank at the level? Since you shouldn't remove the cap when it's up to temperature, that's dangerous unless you have a cap that has a lever and you can release the pressure. The OEM caps don't typically have the pressure release lever and are at they are at about 15.5 PSIG at operating temperature. If you open the cap then the coolant will flash boil and spew out hot coolant and steam.

It's okay to look at the overflow when hot but if you check inside the radiator when the motor is cold; that lets you know the cap is operating properly. It should be sucking coolant back into the radiator as it cools and creates a vacuum.

If you are adding coolant on a regulars basis it would be a good idea to have the radiator cap pressure tested or if it's old just replace it. I replace my caps every so often. I just replaced the cap on our 2013 Outback, they are pretty cheap >> Link<< If it's not holding enough pressure that will slowly boil off coolant. Since it will lower the boiling point of the coolant. If it's doing the opposite, it wont's boil off coolant but hold too much pressure; that can pop a hose or radiator itself. This is why I changed mine, just cheap insurance.

One watch out is be sure the hose that goes from the radiator cap area to the overflow tank is tight. Once I replaced a radiator thinking it was leaking at the upper tank crimp. I saw fluid at the seam figured it was time since the car was 15 years old. Plastic tanks end up needing to be replace at about 10 -15 years. (not a Subaru thing a plastic tank aging thing) It ended up being a loose overflow hose. After I replaced the tank, I saw where it was coming from and put a hose clamp on it which fixed the problem. I need a new radiator and hoses anyway, when your plastic radiator gets old it's not an if but a when it will fail.

Thanks for the info, yes I just look at the overflow tank. I've learned from one of my brothers mistakes of removing the radiator cap when it was hot not to do that lol. My wife's outback has almost 100k miles on it and it's a 2017. I'll buy the radiator cap and replace it just because.

 

[peaty]

Thanks for the info, yes I just look at the overflow tank. I've learned from one of my brothers mistakes of removing the radiator cap when it was hot not to do that lol. My wife's outback has almost 100k miles on it and it's a 2017. I'll buy the radiator cap and replace it just because.

Our 2013 OB has 145K miles now that's why I changed it. We just drove it 15 hrs one way over the holidays. 31Calculated MPG I was pretty amazed. When I was a teenager, my friend removed the cap from his 1964 Ford PU's radiator that was overheating, the cap shot up and ricocheted off the hood and went flying. Steam came out along with some coolant, not fun. I tend to learn the hard way unfortunately

 

[Caracaswest2022]

Well, first of all you should check for any codes that might be street on the ECM, just in case it may not be related but just to make sure that's something else going on.
To make sure that it's a blown head gasket you should make a test, you can get a tester on the autoparts store or online, is the blue liquid test that you do on the top of the radiator, if the liquid turns yellow, the it's the head gasket.
Did the car overheated?

 

[Joe Diamond]

I'm curious how you check when it's up to temp? Are you just looking in the overflow tank at the level? Since you shouldn't remove the cap when it's up to temperature, that's dangerous unless you have a cap that has a lever and you can release the pressure. The OEM caps don't typically have the pressure release lever and are at they are at about 15.5 PSIG at operating temperature. If you open the cap then the coolant will flash boil and spew out hot coolant and steam.

It's okay to look at the overflow when hot but if you check inside the radiator when the motor is cold; that lets you know the cap is operating properly. It should be sucking coolant back into the radiator as it cools and creates a vacuum.

If you are adding coolant on a regulars basis it would be a good idea to have the radiator cap pressure tested or if it's old just replace it. I replace my caps every so often. I just replaced the cap on our 2013 Outback, they are pretty cheap >> Link<< If it's not holding enough pressure that will slowly boil off coolant. Since it will lower the boiling point of the coolant. If it's doing the opposite, it wont's boil off coolant but hold too much pressure; that can pop a hose or radiator itself. This is why I changed mine, just cheap insurance.

One watch out is be sure the hose that goes from the radiator cap area to the overflow tank is tight. Once I replaced a radiator thinking it was leaking at the upper tank crimp. I saw fluid at the seam figured it was time since the car was 15 years old. Plastic tanks end up needing to be replace at about 10 -15 years. (not a Subaru thing a plastic tank aging thing) It ended up being a loose overflow hose. After I replaced the tank, I saw where it was coming from and put a hose clamp on it which fixed the problem. I need a new radiator and hoses anyway, when your plastic radiator gets old it's not an if but a when it will fail.

I am a new guy here..........I just acquired a 2008 Impreza Hatchback in pretty good shape......Early in my shake down I got a red idiot light.......pulled over & let the motor cool. It was then I discovered no coolant ?.....To skip much...I acquired an OBU ( on board unit )...one of many available. I got a Blue Driver. It connects a plug to the data port...sends all dats to my cell phone by Blue Tooth. So now I can fill the coolant ( special funnel ).....and start motoring. The Blue Driver gives me an engine coolant temp gage ....The blue start up light drops off at 122 and normal temp is below 112. It moves around. .........IF you come in off a highway from 60-80 MPH the cooling temp goes way up as the fans come on. At that point the red idiot light com on but only blinks as the fans run......What I found was there was NO oil pressure sensor or oil temp or oil quantity ? There is a sensor that reports catalytic converter temp and voltage to plugs.....No oil info........ SO the Blue Driver is my cure to the primitive data from the 2008 Impreza....which I like....joe

 

[Joe Diamond]

I am a new guy here..........I just acquired a 2008 Impreza Hatchback in pretty good shape......Early in my shake down I got a red " idiot light".......pulled over & let the motor cool. It was then I discovered no coolant ?.....[To skip much.]..I acquired an OBU ( on board unit )...one of many available. I got a Blue Driver. It connects a plug to the under dash data port...sends all data to my cell phone by Blue Tooth.
So now I can fill the coolant ( special funnel ).....and start motoring. The Blue Driver gives me an engine coolant temp gage ....The blue start up light drops off at 122 and normal temp is below 212.( It moves around.) .........IF you come in off a highway from 60-80 MPH the cooling temp goes way up as the fans come on. At that point the red idiot light coms back but only blinks as the fans run...
...What I found was there was NO oil pressure sensor or oil temp or oil quantity ? There is a sensor that reports catalytic converter temp and voltage to plugs.....No oil info.....
... SO the Blue Driver is my cure to the primitive data from the 2008 Impreza....which I like..
..joe

 

[Alex_Rochester]

I am a new guy here..........I just acquired a 2008 Impreza Hatchback in pretty good shape........

You realize I hope, that this is a form for 5th generation Impreza, which were made from 2017-2022. Your car is a 3rd generation model.