Cold Start- Gas Fouling Spark Plugs, Flickering Oil Light, Check Engine Light

[Gemsnake65]

I bought our Aveo Brand new in 2005. Ran great the first couple of years, cold starts in the winter but other then that seemed to run ok however we never got the gas mileage we were promised. In 2008 my daughter was driving the car and it overheated, she had maybe driven it 9 miles, check engine light came on (about 40,000 miles on it at this time) and it was a problem with the thermostat. (We purchased the extended warranty through GM....What a joke that was) Apparently the thermostat isn't covered in the warranty. Oh and then we are informed that we can't just buy a thermostat, we need to buy the complete housing.....well this is about $150. Chevrolet was happy to deliver it to us...my husband got in there and we could not believe what we found...the housing that the thermostat was in was plastic, and melted. The thermostat housing unit, that they replaced it with, was yes folks aluminum...design flaw? Yes I think they new, but instead of recalling it as they should of, the made money off the consumer.

After the overheating we started having non stop problems with it. Cold starts, replacing sparkplugs (that were oil soaked) about every two months. Blowing out white smoke, my husband thinks it is the head gasket because of the white smoke, cold starts, etc. So we take the call to the Local Chevy dealership (Only over 60,000 miles at this point) and we want them to look at it. They want to charge us a "diagnostic" fee. WTH??? It is still under warranty....I don't have the money for the $150.00 diagnostic, so we park the car. Still making payments on it, paying insurance on a car sitting in the driveway. Beyond Frustrating. Well our other vehicle breaks down, so my husband, figures out, if he replaces the spark plugs every couple of months we can get it to run. Still hard to start in the morning, but it is running. Off and on...for the next couple of years. Goal was, get it paid off and get rid of it.

Then the problems get worse. The check engine light keeps coming on. We take it in and it is the 02 sensor before the catalytic converter. My husband gets it replaced. So we are trying at this point to get the car registered, they clear the code, tell us to drive it for a day or two and come back for the emissions. Driving home, check engine light comes on again. Take it back to our mechanic and it is throwing the same code, I think POO13 something like that, but same thing O2 sensor is bad...we just replaced it. Then it started throwing other codes that weren't making any sense. At this point, our mechanic tells us to take it to the dealer and have the computer flashed. We make the appointment, they told us it would be $99.95 to have it flashed by the dealer, so my husband drops the car off, the lady calls my husband as he was leaving work tells him the car is ready for pickup. The girl at the dealership hands him the keys and tells him "NO CHARGE".....with a confused look on her face.

We are once again told in order for it to pass emissions we would have to drive it for a day or two. My husband gets the car home, the oil light starts flashing, and we look down and the oil is flowing all over our driveway. So at this point we park the car again. This was in September 2011. I was unemployed and we couldn't afford to put money in it. Well in May of this year, I got a new job and we needed two running vehicles. My daughters boyfriend who is mechanically sound comes over to take a look at the car to figure out where the oil is leaking from. He finds it right away. It was leaking out the oil sensor, so he goes over to autozone, and replaces it. We had also been told to do the timing belt, so we have an appointment to take the car in and get that done. My husband drives the car for a couple of days, it is running really bad. I had read online that this was a noninterference motor (as are most suzuki motors which at the time is what we thought we had) so I wasn't too worried about the timing. After all when they sold us the car they pretty much told us this was the "new Geo" which always used suzuki parts....well our mechanic calls us and tells us to quit driving it because it is a Daewoo motor and it is and interference motor. Which means if the belt breaks, it will hose the motor. So we tow it too the mechanic and they replace the timing belt. Said the old one was still in surprisingly good shape so he didn't think that it was what was causing the cold starts, rough idling, check engine light, oil light, etc. Well they start the car it fires right over, which is new, but it runs for a few minutes and start choking out. So they diagnose it and find the Catalytic converter is all gummed up. So we replace the Catalytic converter. We had also been having problems putting gas in, we thought that this would resolve everthing. It ran good for a couple of weeks, then, again the same problem, cold start, no start...I am beyond frustrated at this point. I contact GM because I don't care if the car now has 100,000 miles on it, it shouldn't be having all these problems. They tell me in order to figure out what is going on, I have to take it to an Authorized Chevy Dealer for diagnostics. I have a friend of mine that is a certified mechanic for a company called Intermountain Lift Truck, they are basically a mobile mechanic shop. He spend four hours looking at it...can't figure it out. Said the timing is off. So I assume that it wasn't timed right and we take it back to our mechanic. He looks it over and found that the spark plugs have gas fouled. We replace the spark plug, it runs ok for about a week and back to the same problem, check engine light back on, (O2 sensor again), flickering oil light, cold starts, no start, so I finally decide to take it in because this car has been a nightmare. I want GM to fix this. We take it to the dealership, first thing the guy does (it is now September 21, 2012) and hands me a notice on the car. Apparently in June of 2005 (one month after we bought the car) there was a recall on the ECM programming. We were never advised. So they reprogram the ECM and run diagnostics on the car. We pick it up and it is running better then it ever has, well for about 2 weeks. We also found the the Charcoal cannister was gummed up and had to replace it...another $350.00. Well I am pissed about the recall. So I drive the car...check engine light comes on again, we take it back in, again O2 sensor, but now we have a new code. Says the valves are sticking....and we can't just have a valve job, no, we have to replace the whole block.

I contact GM again. I honestly feel that the car has been running to rich due to the problem with the ECM. I also found this service bulletin:

General Motors: 2004-07 Chevrolet Aveo
Subject: Intermittent misfire with or without misfire codes may be caused by poor engine valve sealing. The misfire may occur under any operating condition and may or may not be noticeable. Revised valves are available to solve the problem, and the bulletin notes that vehicles built before VIN 5B406012 may already have the new intake valves installed. The bulletin includes part numbers but no installation instructions.
Bulletin 05-06-01-030C"

To me, this sounds like another design flaw I talk to the lady at GM again and she tells me oh I am so sorry, but the valve problem is due to the age of the vehicle. Really??? I have driven cars with 300,000 miles on them. As long as you keep the fluids full, oil changed, they last.

I am so frustrated with the whole situation. I want to know if anyone else has had these experiences. My next step is to contact an attorney. Who's in?

[Daox]

Sorry to hear about all your problems. I personally haven't had hardly any issues with mine, but I did buy it with a grenaded engine from the previous owner not changing the timing belt.

We can help you diagnose your problem if you'd like...

[Gemsnake65]

Sorry to hear about all your problems. I personally haven't had hardly any issues with mine, but I did buy it with a grenaded engine from the previous owner not changing the timing belt.

We can help you diagnose your problem if you'd like...

If you could tell me what is wrong. That would be great. If the valves are bad, why did it run so good for the first 2 weeks after they reprogrammed the computer?

[Daox]

I can't guarantee anything but we can give it a shot.

It seems like the bulk of the problems started when the thermostat failed. The overheating can warp an engine head and/or ruin a head gasket. This in turn can cause a bunch of problems similar to what you have seen.

Do you know if the mechanic (or anyone) has ever done a compression test or a leak down test on the engine? This will tell if there are head gasket problems or a warped head. It will also detect leaky valves, but I kind of doubt that is the problem.

Another sign would be oil in your coolant, or coolant in your oil. See here about how to detect coolant in oil: http://www.machinerylubrication.com/...k-oil-analysis

Does the car burn oil and/or coolant?

[Gemsnake65]

I can't guarantee anything but we can give it a shot.

It seems like the bulk of the problems started when the thermostat failed. The overheating can warp an engine head and/or ruin a head gasket. This in turn can cause a bunch of problems similar to what you have seen.

Do you know if the mechanic (or anyone) has ever done a compression test or a leak down test on the engine? This will tell if there are head gasket problems or a warped head. It will also detect leaky valves, but I kind of doubt that is the problem.

Another sign would be oil in your coolant, or coolant in your oil. See here about how to detect coolant in oil: Dipstick Oil Analysis

Does the car burn oil and/or coolant?

Compression in the motor is fine. It doesn't burn oil or coolant. And my husband thought it was the head gasket. However there is no coolant in the oil.

[Gemsnake65]

And Ya..they did start when the thermostat failed...but the thermostat failed because the housing melted. It was still under warranty. GM refuses to acknowledge this.

[petrified.rabbit]

the thermostat melting was most likely caused by a larger problem. If it had just split at the seam, that would have been the housings fault.

to me it sounds like you have a problem with oil getting into the cylinder. 3 things tells me this. 1. you say you have white smoke. 2. you have replaced/issues with the o2 sensor. 3. you clogged your catalytic convertor.

Burning oil with do ALL 3 of those. This most likely is caused by the melting housing/overheating.

a compression test will not always give the answer, you need a cylinder leak down test. It doesn't take much oil for the white smoke, the bad o2 and the clogged cat. ALL of which are bad running issues on their own. But i imagine, based on "Design" that your oil return line is what is leaking in the cylinder. This is because you do not see the oil consumption. It is the low pressure side of the oil system, and probably only seeps into the cylinder when not running..

[Gemsnake65]

How do I test for that? We do have oil on the spark plugs...

[Gemsnake65]

Would that also cause the flickering oil light?

[avguy]

Like you I have a 2005 Aveo purchased new, and I also have 2 daughters who drive, so here's my .02. The thermostat cracked (hairline) and started oozing coolant, just like mine did. A bit early for that at 40K, but it happens to all of the plastic ones sooner or later, just like clockwork. The coolant went low over some unknown amount of time, and was way too low on the day your daughter drove it. She didn't notice that the heat gauge was pointing due North (why would that not surprise me), and so it overheated badly. At that point the thermo housing melted and, based on what you've described, some other (more troublesome) things happened as well. The days of the V8 Ford at the top of the hill getting cooled down by the rain are over. Modern engines do not want to be badly overheated. Period.
Now, that being said, there are some things that you've described which may be outside of the engine overheating. As the original owner, what is the full oil change history of this vehicle? Every 4-5K, or something other than that? If the oil-change history is rock solid, then you MIGHT consider doing whatever head gasket/milling, etc. that is currently needed. But if the oil has not been maintained properly, then you might want to consider buying a new engine, if you really want to keep this vehicle for a number of additional years. I believe 2.5K or so gets you a new engine with a year warranty. Maybe some of the other guys have a better take on the current cost of a new motor. I know it's tough to walk away from all of the $$ you've already tossed into this, but you need to know when to fold 'em.
As previously mentioned, the leak down test (done by someone who knows what they're doing) will give you an indication of the engine's current health. Good luck with it in any case!