2G Cooling system question

[pressf1forhelp]

Hey guys,

Since I'm in QT I decided to work on my car.

Car: 1997 Eclipse GST
Millage: 193,xxx

Here's the issue. I get a some white smoke out of the exhaust while idling for a couple of minutes. This will ONLY occur if the engine is at operating temperature. If I continue to drive the smoke seems to die down not to be seen again until I have to idle (long traffic light, heavy traffic jam ect.). I mainly make short trips with this car so I rarely see the issue pop up unless its rush hour. Driving to work I never see the issue show up due to the fact I drive 12ish miles round trip. I even took her on a long 80 mile round trip with no issues majority of the driving being done on the freeway keep in mind.

I hate to admit, but I recently just got my hands on a OBII reader and my CEL has been on for a while now due to a O2 sensor that I can't seem to get to budge out of its home. OBII reader in hand about a week ago I picked up a new code not knowing how long this code has persisted in the logs.

P0170: The bump O2 sensor. I know the code because I friend ran his reader on my car over a year ago. But because I didn't have to smog last year, I kinda didn't really wanna fuss with it. Currently working on it though.
P0125: Something to do with the ECT or thermostat. I replaced the ECT today and burped the system. The problem still persisted.

A lot of people keep on telling me its the HG. But I've seen and owned a car that had a blown gasket before and I just don't think it's the issue and here's why:

-No loss of power
-No miss fires due to coolant in engine
-No "white goo" on oil cap
-Temp gauge is always sitting just like a cm below the optimal operating temperature on the dash
-No issues of starting the car. She turns over right away and purrs happily
-No little bubbles or boiling over from under the rad cap
-As stated in the post, the car isn't ALWAYS letting out this white smoke, only under certain circumstances

I have done these checks yet:

-Compression test
-Chemical block test
-Removing and inspecting spark plugs

What should I do? I'm not afraid to get my hands dirty as I've worked on all the car I've owned since I was 18. I've got a lot of time on my hands right now and I want this issue figured out.

Should I start with a new rad cap and thermostat? I can't find any leaks in the system or on the ground. I do have to refill my coolant every 8 months or so or sometimes not at all. If it is the HG I plan to do it myself because the shops around here are laughable and questionable to say the very least.

Any help would be greatly appreciated and I know I've posted something similar while ago but I didn't want to bump an old thread.

Thanks again!

 

[spyderdrifter]

Poke around everywhere to see if you can spot any old coolant residue that may have burned/evaporated away. Almost sounds like you are burning coolant (such as running hot to where it boils), or it's somehow leaking. Check your oil, see if there's even the slightest odd look to it that makes it no longer look like just oil. Maybe find a scanner or something that'll read your actual engine temp, and compare it to the temp gauge. Could be reading wrong, and not displaying it right. These cars are old, and fail in different ways. Pull your spark plugs too, and see if they are wet.

 

[luv2rallye]

White smoke is always burning coolant from HG or turbo seals. You may have a HG or seal that only opens up at temperature. Use coolant system pressure tester when engine is warm.

 

[ThunderChild]

Could also be from the TB at the FIAV. High vacuum situations pulling coolant into the intake tract from the FIAV and burning it. Still need to pressure test the cooling system when running as @luv2rallye said, as it's possible the hg is leaking directly into the combustion chamber.

Coolant burning in the exhaust will also kill o2 sensors rather quickly, so it may be a related issue. Can pull the plugs and look at piston tops, if they're suspiciously clean then you know you've got coolant in there somehow. If all are clean, then I'd suspect the TB is the culprit, but if single or select ones are, then I'd look at the HG more.

 

[Jk's97DSM]

A pressure tester and soapy water will show if you have a leak and where. Generally a system should hold the pressure rating on the cap if it is correct but I always go to 15-16psi and wait hours to see if it drops.

 

[pressf1forhelp]

Thanks for the replies. I'm going to get the proper spark plug socket tomorrow since mine does not fit and let you guys know what the condition of the plugs are. One thing did strike me as odd though and I just thought about it. When I burped the system, I noticed that only one of my rad fans turned on to cool down the rad. I'm pretty sure that the other one is supposed to as well to compensate for when you sit in traffic ect. Is that correct or is the other fan connected to something else?

 

[luv2rallye]

Check the piston tops as ThunderChild says in post 4.

The 2g fan speeds algorithm is complicated: https://www.dsmtuners.com/attachments/fan-operating-mode-2g-jpg.86862/

 

[pressf1forhelp]

So, I did some shopping. I got a new head gasket and some other long over due things. Below is a picture of the spark plugs. No signs of coolant anywhere on them. I looked at them and even smelled them. The biggest thing I did notice is that the second one I pulled out (from left to right) had a large amount of oil on the end of it. They look extremely dated as well. Is it possible that I'm burning oil due to a bad valve cover gasket or could the oil be leaking into the cooling system causing that weird smoke? Sorry for the quality, I couldn't get my phone to focus but you should get the idea. You guys think I still need to get to the head?

 

[pressf1forhelp]

Just looked at the piston tops. They're pretty dirty, so I'm not sure if it's the HG. Any ideas?

UPDATE: I'm pretty sure I got the issue figured out. Due to that spark plug covered in oil, my friend said that since I'm not experiencing any REAL symptoms to due with HG, time for a valve stem seal job. He had the same issue I was having years ago on one of his cars and everyone thought the HG was the issue but it wasn't. I will update this thread one more time after I finish the job to let you guys know the end result. Otherwise, I will dig deep and do the HG.

 

[luv2rallye]

Leaking valve stem seals will burn oil out the exhaust - not coolant. I just did mine.
But if you do them, get this tool and save yourself a ton of aggravation:
https://www.dsmtuners.com/threads/valve-spring-installation-question.493877/#post-153522062.

And you don't have to remove the head to do just the seals (although you may want to pull the head to check if HG blown on a coolant port also).
Doing seals with head on:
https://www.dsmtuners.com/threads/head-on-block-valve-stem-seal-replacement.312891/
https://www.dsmtuners.com/threads/head-on-block-valve-stem-seal-replacement-part-2.313127/

 

[pressf1forhelp]

Yeah, I'm going to check the HG as well since doing the seals requires taking things off anyway. The smoke I get doesn't smell sweet so I'm kinda doubting the HG but I will check it. The lighting in my car port doesn't help figure out the color of the smoke and driving it doesn't make it easy to stop and look. I'll update you guys in a day or so.

 

[luv2rallye]

Suggest first doing a compression test and leak down test as once the head is off you never can.

Also read this for ideas: https://www.dsmtuners.com/threads/help-with-oil-consumption.482681/#post-153449547

 

[DevineAstral]

Out of curiosity, what sort of setup is the turbo.? Are there any coolant lines running to it.? (Asking because a buddy of mine when replaced his turbo he ran coolant to it as well.) and are you SURE it was oil on the spark plug that you mentioned.? And not the possibility of coolant.? If you have to fill it up so often it has to be burning it from somewhere.

 

[pressf1forhelp]

I'm pretty sure it was oil. Definitely smelt and felt like it. If anything the oil was slightly dirty but no strange discoloration. The rubber covers from the SP wiring had a bit of oil on them as well. As for the turbo set up I'm not sure. I know there's no front mount inter cooler on this car. The car only had two owners before me and they were both mechanics so I don't have much info about any modifications that they did. Not sure where the coolant would be leaking from because I've never seen anything leaking since I've owned the car. Even before this current issue I'm posting about presented itself I was losing coolant somehow. I parked on a large piece of cardboard for over two weeks and no sign of any type of leaking.

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[DevineAstral]

Understandable my dude.! I really don’t really know what else to tell you or where to guide you, sadly. :/. But I do wish you luck in figuring it out.! Just cross your t’s and dot your I’s and double check everything it you could run across it without thinking.

 

[pressf1forhelp]

I appreciate the the help! I have a friend coming over tomorrow and we are gonna tear the engine bay apart. Ultimately I plan to do the HG for peace of mind and the valve stem seals. I will update this with a final post to insure that if someone else runs into this issue they will have a solution.

 

[DevineAstral]

I eagerly await your results my man.!

 

[luv2rallye]

Since you say you are losing coolant, I recommend doing a coolant pressure test before dismantling anything (engine warm but stopped). Perhaps it really is going into a cylinder (or the oil) due to a blown HG and you could see coolant in a cylinder with the spark plugs removed. At bare minimum it would be nice to know if the pressure drops or is maintained.

 

[pressf1forhelp]

Luckily, I haven't got too far in the dismantling process. I can do the pressure test tomorrow to see what it says. I'm picking up tools tomorrow to swap out the valve stem seals to see if that fixes the problem. There seems to be a lot of oil around the head so I know the valve gasket is an issue as well. I just find it hard to believe its the HG because I've never had the engine overheat or my oil and coolant mix or a lack of power.

 

[Harrison Scholten]

If you aren't getting any oil and coolant mixing then it's not likely to be a head gasket. It seems to me like it's coming from the turbo. One thing I am wondering is what thermostat you have in the car, if it's too high a temp or faulty it might be building too much system pressure when the engine is hot as it would be especially when idling for long periods of time.

 

[pressf1forhelp]

If you aren't getting any oil and coolant mixing then it's not likely to be a head gasket. It seems to me like it's coming from the turbo. One thing I am wondering is what thermostat you have in the car, if it's too high a temp or faulty it might be building too much system pressure when the engine is hot as it would be especially when idling for long periods of time.

I think a few posts back, I mentioned I do not know any prior history of the car. So I have no clue as to what thermo is in there. A lot of people were thinking this as well but I quickly dismissed because I didn't think it would cause the current issue I'm having or to the extent that I'm having at least. I can check the thermostat tomorrow and just replace it since I have a new one I plan to put in anyway. It's temp is 180 deg for the replacement which I think is right.

What exactly am I looking for on the turbo? Just leaks or bad rings or like replacing the turbo and lines? I'm not sure if there is coolant being sent to the turbo, but there's one way to find out.

Edit: I'm still curious about the spark plugs covered in oil. Is that from a bad valve cover gasket? If so, is it causing a load of oil to combust causing my car to burn oil consistently? I usually have to fill 2qt to get to half full every two months. I don't drive her like all over the place, mainly short trips so filling 2qt doesn't seem like much but seems average if I were driving the car A to B on longer trips almost everyday. Would this cause the smoking to any extent?

 

[pauleyman]

I think a few posts back, I mentioned I do not know any prior history of the car. So I have no clue as to what thermo is in there. A lot of people were thinking this as well but I quickly dismissed because I didn't think it would cause the current issue I'm having or to the extent that I'm having at least. I can check the thermostat tomorrow and just replace it since I have a new one I plan to put in anyway. It's temp is 180 deg for the replacement which I think is right.

What exactly am I looking for on the turbo? Just leaks or bad rings or like replacing the turbo and lines? I'm not sure if there is coolant being sent to the turbo, but there's one way to find out.

Edit: I'm still curious about the spark plugs covered in oil. Is that from a bad valve cover gasket? If so, is it causing a load of oil to combust causing my car to burn oil consistently? I usually have to fill 2qt to get to half full every two months. I don't drive her like all over the place, mainly short trips so filling 2qt doesn't seem like much but seems average if I were driving the car A to B on longer trips almost everyday. Would this cause the smoking to any extent?

Yes the oil is a bad valve cover gasket. No you're not burning oil that way. You can't. Just remember spark plug insulator is outside the combustion chamber and can't leak into it. Spark plug screws in and is sealed. Valve cover not only has the outer gasket but four spark plug well gaskets. For some dumb reason sometimes they are sold separately.

 

[chrysler kid]

Compression test the motor. If you have bad valve stem seals your car will have perfect compression numbers because the cylinders are coated in oil

 

[pressf1forhelp]

If you aren't getting any oil and coolant mixing then it's not likely to be a head gasket. It seems to me like it's coming from the turbo. One thing I am wondering is what thermostat you have in the car, if it's too high a temp or faulty it might be building too much system pressure when the engine is hot as it would be especially when idling for long periods of time.

In response to this. I took out the old thermostat. It was crooked and somewhat seized shut. It took me 15 minutes just remove the damn thing from the housing. So pretty dated. Any thoughts on this?

Compression test the motor. If you have bad valve stem seals your car will have perfect compression numbers because the cylinders are coated in oil

Will check this at some point before I change out the stem seals. I'm currently working on getting the valve cover off to replace the gasket.

 

[Harrison Scholten]

In response to this. I took out the old thermostat. It was crooked and somewhat seized shut. It took me 15 minutes just remove the damn thing from the housing. So pretty dated. Any thoughts on this?



Will check this at some point before I change out the stem seals. I'm currently working on getting the valve cover off to replace the gasket.

If you aren't burning any oil your valve stem seals are probably okay, a little oil in the engine is normal as long as the pcv system is still attached properly.
As far as the thermostat goes all you can do is try it, and even if it wasn't the cause, it probably needed to be changed anyway

There are only 3 places where coolant can get in the exhaust, the idle air control valve, the head gasket, or from the turbo seals,. The biggest indicator of a headgasket leak is oil and coolant mixing. If it's the turbo seals you'll get some mixing but also alot of white and blue smoke.