Chevy Sonic Falling Apart!

[trollbait]

HEET is a name brand and there are several versions that do the same thing. Lucas seems to have the most expensive but a store brand seems effective to me (Meijers in my case.) I also use marine grade Sta-Bil in my Corvair as ethanol seems to attract water in the fuel tank but would not recommend its use for a "daily driver" but regular Sta-Bil might be an option if where you buy fuel does not sell huge amounts every week. (I use marine grade because the Corvair engine is aluminum block.)

The problem described in the original post seemed to me to be a result of water in the fuel tank which is not readily seen by the diagnostic machine the dealers use although some of the other possibilities posted also seem just as likely. I think using HEET first is a good idea.


Laborsmith

HEET is just methanol, and Iso-HEET isopropanol. Denatured alcohol sold in the paint aisle is around a 50/50 mix of methanol and ethanol. I usually use 91% rubbing alcohol which is isopropanol. Acetone will also remove water, but you have to watch the paint.

On a related note, Klean Strip paint thinner(not the low odor) is pretty close to the generic injector cleaners.

 

[MartyH]

In simple terms it sounds like your Sonic was flogged. Maybe you need a good shop to go through this car and try to get it tightened up so to speak. My Sonic has been flawless to date from new. 24,000 miles.

 

[laborsmith]

I do not recall hearing tire humming on the OEM Hankooks. If the tires have been changed that could be possible depending on how aggressive the tire tread is.

As for the CEL I would just clear the code and see if it comes back. AutoZone etc reads/clears and local auto service garages do it too.


Laborsmith

 

[wasteoffilm]

That coil pack is broken, and at minimum, should be epoxied back together or just replaced. The plastic that the boot slides on is broken off inside the boot, you no longer have a seal against moisture.

Speed dependent vibrations/noises are usually tires or wheel bearings. Try to get in the speed where it is the loudest, and make some mildly aggressive lane changes. Shifting weight off of a bad wheel bearing will usually affect the noise level.

Also, try shifting up/down/neutral at that speed. If the noise remains steady with a constant speed, you can rule out engine and exhaust.

Have a helper sit in various positions in the car and see if one corner is louder than another.

 

[t_forey]

Alright everyone, thanks again for more information on what to check out. I called up Chevrolet (Headquarters) and explained to them that the dealers around me were saying they wouldn't even check the car out unless I payed up front $100 for diagnosis.

Chevy got me hooked up with a dealer just south of me and told them how it was apparently. Spoke with the service manager and he said there wouldn't be a charge until they find out what's wrong with it.

Took it in Tuesday afternoon and they got back with me yesterday morning. They said the valve cover was leaking air into the combustion allowing the car to run lean, which is why the engine light was on. They said the roaring noise coming from the front end was a wheel bearing that had gone bad. Then they said my coil pack was damaged (could have been what I had seen when changing the plugs) and was needing to be replaced.

They said the valve cover was covered under powertrain. But the coil and wheel bearing was covered under my aftermarket warranty. All in all I am only having to pay a deductible to the warranty company, total: $100. I'm satisfied. Glad to finally know what was going on and that it was much bigger than what I had originally thought. Hoping to get it back today, maybe tomorrow morning. I'll be back on a let you all know how it drives once I get it back.

Thanks everyone,

Taylor

 

[sx sonic]

Good deal, progress at last.

 

[Larrymer]

sounds kind of like a warped block

No, it doesn't.

Just a couple minor issues and one bad dealer results in a ridiculous thread title that's going to scare people about Sonics. Sweet.

 

[laborsmith]

So wasteoffilm on point.

Laborsmith

 

[Chevrolet Customer Care]

Hey Taylor,

It's great to see that your issues have been resolved with your Sonic! As always you can let me (or Erica) know if you need any assistance by sending me a private message!

Jackie
Chevrolet Customer Care

 

[Whitjr]

This is just my nickel's worth, however I'd wonder what sort of driving the PO did. did he abuse that motor and tranny? did he give the car a proper break-in? All sorts of problems occur when a new engine is abused, and not given a chance to break in properly.

 

[ahtoxa]

This is just my nickel's worth, however I'd wonder what sort of driving the PO did. did he abuse that motor and tranny? did he give the car a proper break-in? All sorts of problems occur when a new engine is abused, and not given a chance to break in properly.

Eh, one could argue that break-in matters FAR less than it used to. Better tooling, more precise tolerances, better lubrication, etc....

I can't tell you how many people buy a new car and drive it no differently than they would otherwise. Cold starts, hard driving when cold, etc. I'd wager that most of the break-in occurs BEFORE one even buys the car - the first few miles. Most new cars are sold with at least 2-3 miles on the odometer, which includes driving out the factory, in the ports and during other transport. Most of the initial break-in happens then anyway.

 

[ChrisJ]

Eh, one could argue that break-in matters FAR less than it used to. Better tooling, more precise tolerances, better lubrication, etc....

I can't tell you how many people buy a new car and drive it no differently than they would otherwise. Cold starts, hard driving when cold, etc. I'd wager that most of the break-in occurs BEFORE one even buys the car - the first few miles. Most new cars are sold with at least 2-3 miles on the odometer, which includes driving out the factory, in the ports and during other transport. Most of the initial break-in happens then anyway.

Personally I've only broken one engine in, or at least what I felt was actually "breaking an engine in". It was a 2005 Raptor 350 ATV and the engine ran UNBELIEVABLY hot for the first 20 minutes or so. It also felt very tight. After the first 20 minutes things loosened up and cooled down. Unbelievably hot means an air cooled engine that feels like its going to burn the hair off your legs on a chilly fall day going down the road. There was nothing wrong with the engine, it was just breaking in. I did an early oil change on it after maybe 30 minutes or an hour of running and the oil had some silver in it. Again, never seen this on a modern new car either.

Every new car I've bought didn't show any signs that ATV did so I suspect you're 100% right. Modern cars are 99% broken in before they get to the dealer.