Rough idle and no power?

Tiny
CMCCLAMMA
  • MEMBER
  • 2015 CHEVROLET SONIC
  • 1.4L
  • 4 CYL
  • TURBO
  • 2WD
  • AUTOMATIC
  • 86,000 MILES
Okay, here’s a little history: Less than a month ago I replaced the purge valve because of the check engine light code. Shortly after that, the car begins to overheat. It was also losing coolant when it overheated. I looked at it and seen the thermostat housing was leaking. When I started the car to pull it in the garage to replace the thermostat, it was running really rough and idling really rough. After I replaced the thermostat. It was no longer doing this when I test drove it. So, the overheating problem was solved, and it was running fine. About the fourth time I started the car after that repair, it began running rough again and idling rough. It did this about two to three times. Then the next two starts It ran fine. The last time I started it, it was running really rough again, but this time it had absolutely no power when I pressed the gas. I pulled the ignition coil and checked the spark plugs. And one of the spark plugs had oil in the well but not a lot. About six months ago I replaced the valve cover gasket, but I did not check the spark plugs. The spark plug that had oil in it was so loose that I could take it out by hand. The other three spark plugs look great. I'll replace the one with oil in it. I've only started it twice since and it's been fine. Is there anything else that could be causing this that I'm missing? Any advice would be awesome. This is my elderly mother's car. And she has to make frequent trips to a doctor, about an hour and 15 minutes away. So, I have a lot of concern about this car being safe for her and not leaving her stranded on the side of the road.
Tuesday, November 1st, 2022 AT 12:58 PM

25 Replies

Tiny
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Update: Car won't start now at all. It does a long crank but won't start. I've even tried to turn the key on for about 30 secs to let the fuel pump pressurized. Also, during two of the rough idle starts the check engine light was flashing and the icon with the car and skid marks was lit up. Both lights went off after about 10-15 seconds.
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Tuesday, November 1st, 2022 AT 3:06 PM
Tiny
JACOBANDNICKOLAS
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Hi,

When the check engine light was flashing, that indicates a misfire was taking place at that time.

Now that it doesn't start, I need you to do the following. First, see if the engine starts for a couple of seconds if you use starting fluid. If it does and then stalls, we know it is a fuel-related issue. If there is no change, then we need to expect the issue is ignition related.

At that point, we need to check for spark to the plugs.

Here is a link that explains how that is done:

https://www.2carpros.com/articles/how-to-check-for-ignition-spark

Try this and let me know the results. Additionally, if you have a scan tool, see if there are any diagnostic trouble codes stored or pending, and let me know what they are.

Take care,

Joe
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Tuesday, November 1st, 2022 AT 7:53 PM
Tiny
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Hi Joe,

Thanks so much for your response. I have never used starting fluid before. Not trying to sound like a complete idiot, but where do I spray it? Do I need to spray it and have someone try to start the car at the same time? How much do I spray?

Thanks!
Candace
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Thursday, November 3rd, 2022 AT 2:39 PM
Tiny
JACOBANDNICKOLAS
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Hi,

You will need to spray it into the throttle body. If you follow the air intake tube from the air filter, it will lead you to the throttle body.

I attached the only pic I could find below. I have an arrow pointing to where to spray the starting fluid. Just give it a brief spray (1 second) and then try starting it.

Keep in mind, it will evaporate fast, so don't wait too long to try starting it. Also, just as a safety precaution, make sure you remove the spray can away from the engine when you try starting it.

Let me know if this helps and by no means is this a stupid question. I'm glad you asked.

Take care of yourself.

Joe
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Thursday, November 3rd, 2022 AT 8:10 PM
Tiny
CMCCLAMMA
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I tried the starting fluid in the throttle body first. The car did start but it stalled after a few seconds. I put the hose back on the throttle body and cranked the car again. This time the car stayed running but there was a lot of white smoke coming from the exhaust. I turned it off when I see that.
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Friday, November 4th, 2022 AT 11:55 AM
Tiny
JACOBANDNICKOLAS
  • MECHANIC
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Hi,

When you say excessive white smoke, it concerns me. Have you noticed any engine coolant usage? I ask because if coolant enters the combustion chamber, it burns white. However, if there is a lot of condensation in the exhaust, it will produce steam, so we need to make a determination.

Take a look through this link and let me know your thoughts:

https://www.2carpros.com/articles/head-gasket-blown-test

The link reviews different things, but the white smoke is discussed. See the pic and let me know if that is what you saw.

Let me know.

Joe
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Friday, November 4th, 2022 AT 8:17 PM
Tiny
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Yes! There has been a small amount of coolant usage for several months now. I would just always make sure it was full before she went anywhere. Then the other day, the car overheated. She pulled over immediately and called me. Now I could see coolant leaking from around the thermostat housing. So, I replaced that and no more leaks. But it was still using a small amount of coolant. It kind of makes sense to me that coolant is leaking into the combustion chamber. Because when the car wouldn't start a couple of days ago, she tried to crank it several times. I tried two or three times. And when I got it towed home, I popped the hood and noticed there was absolutely no coolant in the overflow. Should I perform the test where you take the spark plugs out to see if there is coolant coming up when you try to crank the car? Do you think a head gasket repair would fix this?
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Friday, November 4th, 2022 AT 10:54 PM
Tiny
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Hi,

You can try that test. Also, check the condition of the motor oil. There are other tests that can be done such as a compression test. Since you will have the plugs removed, that would be the time to do it. If we have a bad head gasket, compression will be lower in one or more of the cylinders.

Here is a link that explains how it's done:

https://www.2carpros.com/articles/how-to-test-engine-compression

Let me know what you find. If you are able to get it running again, pay attention to see if there are any air bubbles in the coolant.

If it needs a head gasket, I'll get you through it.

Take care,

Joe
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Saturday, November 5th, 2022 AT 9:56 PM
Tiny
CMCCLAMMA
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Okay, here's the latest: there's definitely coolant in the oil. That was confirmed when I took off the oil cap (pic 1 and 2). I also did the cylinder compression test. When I removed the ignition coil, I could see coolant on the boot (pic5). The same spark plug that had oil in the spark plug well before now had coolant as well (pic3). There results from the compression test are:
Cylinder One: 150 PSI.
Cylinder Two: 140 PSI.
Cylinder Three: 140 PSI.
Cylinder Four: 180 PSI.

I performed the test three times on each cylinder to ensure the results are correct. So, I'm going to take an uneducated guess and say it's a blown head gasket? If so, do you think something like K&W Head Gasket Block and Repair will fix it? I have a brand-new bottle of this that I bought when I thought I had a blown head gasket in my jeep. (Thank God that I didn't). I'm not scared to do the repair but if that bottle of stuff will fix it then that would be a lot easier. Let me know what you think.
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Sunday, November 6th, 2022 AT 3:00 PM
Tiny
JACOBANDNICKOLAS
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Hi,

It won't hurt to try. I'm not familiar with the product you have. I have heard that Blue Devil brand works well if the directions are followed. However, I don't think any of them are permanent fixes.

Looking at the oil in the pics certainly appears to indicate coolant is mixing. Whatever you do, make sure to change the oil and filter prior to starting it after repairs.

Let me know what you decide. If you try what you have, let me know the results. If you want to replace the gasket, let me know that as well and I'll help you through the procedure.

Take care,

Joe
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Sunday, November 6th, 2022 AT 7:47 PM
Tiny
CMCCLAMMA
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I decided to try the head gasket repair in a bottle. I changed the oil and filter prior to the bottle repair. I followed the directions and during the time the car was idling it overheated. I checked the coolant, and it was a tiny bit low. Also, while the car was idling the heater never got hot. It was barely warm. The amount of time the car was on, the heater should have been hot. I swear I'm about ready to call a scrap yard to come get it!

Positive note: The car started immediately. Not even the long crank. So that's a good thing!

Also, I checked the oil after it overheated and it was not milky.
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Tuesday, November 8th, 2022 AT 4:31 PM
Tiny
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When you refilled the coolant, did you open the air vent on the radiator to help eliminate trapped air in the system? That is what it sounds like is causing the heater issue and likely the overheating.

Take a look at the directions below and let me know if it is what was done.

Let me know.

Joe

See pics below.
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Tuesday, November 8th, 2022 AT 7:25 PM
Tiny
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No. I did not do this.
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Wednesday, November 9th, 2022 AT 8:39 PM
Tiny
JACOBANDNICKOLAS
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Hi,

Give it a try and see if it makes a difference. I suspect there is an air pocket causing the issue. If you follow the directions above, it should resolve the issues.

Let me know if it helps.

Take care,

Joe
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Wednesday, November 9th, 2022 AT 9:04 PM
Tiny
CMCCLAMMA
  • MEMBER
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Here's the latest: So, I think the reason it overheated the last time was my fault. The gasket repair says to put it in the upper radiator hose if the radiator cap is inaccessible. Well upon further inspection I actually put it in the surge tank hose. Major rookie mistake. That hose goes into a T. I removed all of these hoses and the T and cleaned it out. The repair didn't go past the T. So, this time I put it in the correct radiator hose and topped off the coolant. I also did the steps you sent me when topping it off. It's not overheating, and the coolant level is holding. Everything seems to be working fine. There's just one thing. When I removed the oil cap it was milky looking again. The dipstick is fine, no white smoke, no bubbles in the coolant. Could this be leftover from before, even though I changed the oil?
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Monday, November 14th, 2022 AT 11:02 PM
Tiny
JACOBANDNICKOLAS
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Hi,

If you wipe that out, does it return? Also, have you noticed any coolant usage?

It could be residual. Let me know about the coolant and if it will return. Also, keep in mind a faulty PCV valve can restrict crankcase air flow resulting in condensation in the engine as well. That can cause what you see in the pic. Check that too.

Let me know.

Take care,

Joe
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Tuesday, November 15th, 2022 AT 7:15 PM
Tiny
CMCCLAMMA
  • MEMBER
  • 25 POSTS
I wiped it out and drove the car several miles. There was a small amount of that stuff that was there again. There has been zero coolant usage. The level has not changed at all. As for the PCV valve, wouldn't that cause the check engine light to come on and a rough idle? I don't know anything else about the PCV valve besides those two symptoms. Do you think that before I go down that rabbit hole that I should do another oil change just in case it's residual?
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Thursday, November 17th, 2022 AT 6:26 PM
Tiny
JACOBANDNICKOLAS
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Hi,

If there is a leak from the PCV hose, it will cause a rough idle and likely set a code. If it is clogged, that can cause the additional condensation in the engine block.

Just for the heck of it, disconnect the PCV hose and valve. Inspect them to make sure nothing is plugging the hose and that the valve is clear.

Let me know if I can help.

Take care,

Joe
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Thursday, November 17th, 2022 AT 8:41 PM
Tiny
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I know absolutely nothing about the PCV valve. I really can't find anything about it either. Not for this make/ model and engine. Can you tell me how to do all of that please?
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Saturday, November 19th, 2022 AT 1:42 PM
Tiny
JACOBANDNICKOLAS
  • MECHANIC
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Hi,

This is a little different because it is a turbo. The PCV hose is shared by the charge air tube. I attached two pics below showing things from two different angles. Note that the arrows in the pics are pointing toward the front of the vehicle.

In pic 1, I circled the start of the PCV hose. All things highlighted are related. I need you to check for any leaks in the hoses indicated as well as the smaller hoses.

When you do this, make sure nothing is cracked or allowing air to escape.

Let me know what you find. Also, please feel free to let me know if you have any questions. It is absolutely not a problem whatsoever.

Take care,

Joe
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Saturday, November 19th, 2022 AT 8:18 PM

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