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Discussion Starter #1 (Edited)
Hello!

I just bought a 2012 base model with a million miles on Friday and am loving it. I'm going to be 35 in June and have had around 30 vehicles since I got my license, but I think this is one that I'll hang on to. I'm coming from a 1999 BMW 540iT, so quite a change.

Anyway, here is some I do that I shared in the last forum I was a member of and I think it was helpful. It should still be in terms of the gas engine at least on this platform.

If you are having engine trouble and have a code or not, there is a cheap and easy way to let the community help you out. Sharing engine data can really help eliminate the need to just change parts on your car, hoping the problem goes away.

The easiest way I have found, if you have a smart phone, is to download an app such as torque pro, and buy a obd2 Bluetooth adapter.

I am only familiar with the torque app but there are others to choose from. I paid $5 for the app and $10 for the adapter, which just broke. I'll get another one soon. Just get one that has good reviews.

The helpful part is posting screenshots of the data.

It is really helpful to get an understanding of how the computer works to keep the engine running efficiently, and to do that I suggest watching some YouTube Videos and read up on long and short term fuel trims. After binge watching hours of videos on schrodingers box and ScannerDanner channels, I look at problems totally differently and can immediately cross items off the list before I start buying parts.

Members can walk you through what information to post and under what conditions once you have the set up I mentioned above. Its really hard, if not impossible, to beat a set up like that for the price. I have spent so much more money on scan tools that do less in the past.

Most of these setups will only show you emissions related engine data, so you won't be able to see abs, airbag, transmission info, or anything else. You can read and clear engine codes.

If you are having problems and no codes, the first place you can look is long and short term fuel trims to get an idea of where to go.

If everyone started a post with their symptoms and some basic data like this, people would save a lot of money and everyone would learn a whole lot more.

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Discussion Starter #3 (Edited)
To add some information to this to include what you are looking at with the numbers.

Long Term fuel trims are a base point that shows how much fuel is being added or decreased from its originally anticipated values.

Short term fuel trims are instant changes to the base point that the ltft set in order to keep the mixture of air and fuel to a precise 14.7:1 ratio. This is achieved by using properly functioning o2 sensor to how the mixture burn actually is vs what the other sensors are telling the computer.

Example: if you have a new car with ltft and stft values of 0, and pull a vacuum line, the stft will instantly rise, to say 15%. This is because to run at a 14.7:1 ratio, there must be more fuel added to compensate for the additional air that bypassed the maf sensor. If you wait a few minutes, the ltft will eventually rise to 15% as well and set that new base point. Once the point is set, the stft will go to 0 and monitor and changes from that new plot.

Of you fix the leak, the stft will go to -15% and the ltft will set back to zero. After that new base is set, the stft will go back to 0.

These numbers are all set on a table based on load, rpm, and other values, so they may differ in different circumstances.

A vacuum leak will typically show high values at idle and then more normal values with some added rpm. This is because the vacuum leak introduces a relatively small increase in air that is then covered up by the large increase of air when the throttle plate is opened. I'm not sure how you would increase rpm manually with the gas engine though.

If your ltft values increase with rpm, you may have a dirty maf or fuel delivery issue. If your fuel pump is dying and can't keep up with fuel demands at idle, it will be telling the injectors to stay open longer (higher fuel trims) to make up for the lack of fuel. With more rpm, there is a greater deficit that needs to be accounted for, therefore, even higher trim numbers with more rpm. The same goes for a dirty maf sensor, the sensor is not reporting the proper amount of air because it is dirty and the more rpm, the more fuel needed. So, a rise of trim with rpm. I guess you would just have to watch the rpms to see what happens as the engine increases them as you don't have control over this function.

If you have high values on one bank and not the other, you can eliminate issues that would impact two banks, like maf or fuel pumps. If they are only in one bank, you can check out bank specific issues like vacuum leaks and injectors.

This is confusing, so ask questions. There are a lot of people in here who know more about this than I do who will help too.

The idea is that you get direction on what to look for and not just throw parts at it and guess.



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Congrats on the new ride. 30 cars since you've gotten your license? Man that's an awful lot of cars. Meanwhile I've only purchased 4 cars between me and my wife in our lifetime and I'm 50 years old. I got two more for free (college car from my dad, and later he gave me his retirement car (which I hated, but an 8 year old Deville with only 26k miles on it for free was, well, free).

All this talk about keeping the engine running efficiently goes out the door when many folks just keep their ICE engines off, using all electric for their commutes.

A million miles you say? I think you're definitely exaggerating there. I'd never buy a car with a million miles on it as by then the drivetrain is toast.
 

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You said a million miles... ain't possible and I'm thinking we have a troll.
 

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You are welcome here, but you will find this is different than what you are used to in car related internet forums.

You are not getting a massive welcome because 99% of the people here are still under the first generation volt 5 year / 100,000 mile powertrain warranty. If something goes wrong they take it to the dealer and it is Chevy's problem to figure it out and fix it. Also, unlike BMW this forum is (with some exceptions) not a group of car guys... they are not interested in getting their hands dirty, if they plan to keep their current Volt they are interested in the best price on an extended warranty, not in how to diagnose and fix problems themselves.

This may change over time,

Keith
 

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Welcome to the forum tutti57. You have a high mileage Volt and that means it must have used some gas. Your observations will be important here as more Volts pile on the miles. Torque Pro can help you learn more about your HV battery. Also search the forums for info on how the two electric motors and the one speed transmission work.
Most owners run away from a car with minor problems like a bad sensor or vac leak. They lose money in the process. You can help.
 

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About 30 cars in about 16 years? Why? Does the OP get bored with them quickly or does he mess them up quickly?
A million miles on it and he thinks this is the car he'll keep for awhile?

Welcome to the forum. Should be entertaining.
 

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You are welcome here, but you will find this is different than what you are used to in car related internet forums.

You are not getting a massive welcome because 99% of the people here are still under the first generation volt 5 year / 100,000 mile powertrain warranty. If something goes wrong they take it to the dealer and it is Chevy's problem to figure it out and fix it. Also, unlike BMW this forum is (with some exceptions) not a group of car guys... they are not interested in getting their hands dirty, if they plan to keep their current Volt they are interested in the best price on an extended warranty, not in how to diagnose and fix problems themselves.

This may change over time,

Keith
*8* year/100,000 mile Voltec warranty. Which means nobody exceeds that warranty except by miles for another 2-3 years.

And it's less a question of "getting hands dirty" than not really seeing a whole lot of benefit. It's NEVER going to be a five-second car. If you want a five-second car, there's plenty of MUCH CHEAPER ways to make a five second car. There's never going to be a lot of interest in top speed changes until someone publishes how to turn off the speed limiter. Otherwise it's always going to be hitting a wall at 101MPH and every Volt can get there. (Unless it's broken, anyway, and it probably won't even go 70 if it is.) Even fuel-efficiency gets less interesting when most Volt owners spend more money on car washes and little tree air fresheners than gasoline. (Literally. Last week I put the second $15 into the tank THIS YEAR. Prior car would burn $30 worth of gas in a week sometimes.)
 

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About 30 cars in about 16 years? Why? Does the OP get bored with them quickly or does he mess them up quickly?
A million miles on it and he thinks this is the car he'll keep for awhile?

Welcome to the forum. Should be entertaining.
Heh. A friend of mine likes fixing mistreated ones, and gets bored of them when they're back in good shape. He's owned over 120 of them now, mostly for 4-6 months at a time. I think he's got four in the barn this week.
 

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Discussion Starter #13
I used the word vehicles to include some motorcycles as well. It started with me getting some enjoyment buying a $200 car and driving it for 6 months to a year. I originally did this since I had a car that I didn't drive in the snow.

I'm not talking about making the volt faster. I'm talking about the satisfaction of not having to pay someone to fix something you can do yourself.

I feel like that should translate pretty well to a community interested in efficiency and saving money, no?

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Discussion Starter #14
Welcome to the forum tutti57. You have a high mileage Volt and that means it must have used some gas. Your observations will be important here as more Volts pile on the miles. Torque Pro can help you learn more about your HV battery. Also search the forums for info on how the two electric motors and the one speed transmission work.
Most owners run away from a car with minor problems like a bad sensor or vac leak. They lose money in the process. You can help.
Thank you! At least someone gets where I'm coming from here. I'm happy to help any way I can.

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Heh. A friend of mine likes fixing mistreated ones, and gets bored of them when they're back in good shape. He's owned over 120 of them now, mostly for 4-6 months at a time. I think he's got four in the barn this week.
Yeah, there's that. If that's his interest.
 

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Thank you! At least someone gets where I'm coming from here. I'm happy to help any way I can.

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Many of us get it. But most of us have cars still under warranty and don't need to fix things yet. Also the car is different and the design does not lend itself to traditional modification schemes. Troubleshooting an engine issue is likely a long way off for most of us. At 100k miles my engine will likely have about 20K on it. Won't even need a tune up yet. Most modern engines go a 100k without much more than oil changes.
 

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Discussion Starter #20
Many of us get it. But most of us have cars still under warranty and don't need to fix things yet. Also the car is different and the design does not lend itself to traditional modification schemes. Troubleshooting an engine issue is likely a long way off for most of us. At 100k miles my engine will likely have about 20K on it. Won't even need a tune up yet. Most modern engines go a 100k without much more than oil changes.
True, and tune ups don't really exist anymore. If something does come up, then you have to deal with it.

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