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Air/Fuel rich.

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Old Sep 5, 2015 | 02:50 PM
  #1  
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Air/Fuel rich.

My car is running rich and I feel like its robbing power from my car, I don't know what other thing it could be, now the question would be, how do I get my ratio back normal?
Old Sep 5, 2015 | 03:30 PM
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What's it running at right now?
Old Sep 5, 2015 | 05:28 PM
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Air/Fuel rich.

I'm not sure but it's definitely rich from smelling excess gas from the back end
Old Sep 5, 2015 | 08:38 PM
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Do you still have your catalytic converter? I removed mine, and every so often I get to smell this wonder of a smell when I walk behind my car.
Old Sep 5, 2015 | 09:21 PM
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Air/Fuel rich.

Cat is still sittin right where it is supposed to be
Old Sep 6, 2015 | 09:49 AM
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I just had a similar problem with the car running very rich. It turned out to be the MAF even though it wasn't throwing any codes for it. We had to drive it with a scan tool that let us watch the MAF output to diagnose it.
Old Sep 6, 2015 | 09:56 AM
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Originally Posted by Derrick2k2SE
I just had a similar problem with the car running very rich. It turned out to be the MAF even though it wasn't throwing any codes for it. We had to drive it with a scan tool that let us watch the MAF output to diagnose it.
Good suggestion. The MAF is a frequent problem in our cars.

The input from a large number of other sensors influences ECU's decision re. how wide the injection pulse should be (the width of the pulse determines the amount of fuel injected). They are listed on page EC-30 of the FSM. If your MAF turns out not be the source of your problem, then checking these other sensors may be necessary.
Old Sep 6, 2015 | 11:10 AM
  #8  
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Air/Fuel rich.

Originally Posted by maxiiiboy
Good suggestion. The MAF is a frequent problem in our cars.

The input from a large number of other sensors influences ECU's decision re. how wide the injection pulse should be (the width of the pulse determines the amount of fuel injected). They are listed on page EC-30 of the FSM. If your MAF turns out not be the source of your problem, then checking these other sensors may be necessary.

Thanks guys, how would I check the maf for faulty?
Old Sep 6, 2015 | 01:32 PM
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Your best bet here may be to pay a mechanic to help you diagnose the problem.

If you find someone good, they'll be able to plug in a scan tool and view the data streams as you drive. This is beyond just looking for a stored code. If it's running rich, there's some sensor that's not reading correctly. A good mechanic will recognize that and be able to diagnose the problem.

You can usually pay a "diagnostic fee" for this type of service.
Old Sep 6, 2015 | 03:29 PM
  #10  
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Air/Fuel rich.

Originally Posted by Derrick2k2SE
Your best bet here may be to pay a mechanic to help you diagnose the problem.

If you find someone good, they'll be able to plug in a scan tool and view the data streams as you drive. This is beyond just looking for a stored code. If it's running rich, there's some sensor that's not reading correctly. A good mechanic will recognize that and be able to diagnose the problem.

You can usually pay a "diagnostic fee" for this type of service.
I see, I just adjusted the timing up by two degrees, will that do anything with air/fuel?
Old Sep 6, 2015 | 05:27 PM
  #11  
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Originally Posted by AT978
I see, I just adjusted the timing up by two degrees, will that do anything with air/fuel?
It shouldn't.
Old Sep 6, 2015 | 06:45 PM
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Originally Posted by AT978
Thanks guys, how would I check the maf for faulty?
It's difficult, and most mechanics can't do it as you need special tools that only dealers have. The simplest solution is to replace your MAF with another one (a good one, from a friend's car) and see what happens. Since the MAF is a common problem on our cars, I purchased a "spare" one just for this purpose. You can get it from courtesyparts.com for just $77 plus shipping. One day, your MAF will fail hard so purchasing the spare one is not a waste of money.
Old Sep 6, 2015 | 09:29 PM
  #13  
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Air/Fuel rich.

Originally Posted by maxiiiboy
It's difficult, and most mechanics can't do it as you need special tools that only dealers have. The simplest solution is to replace your MAF with another one (a good one, from a friend's car) and see what happens. Since the MAF is a common problem on our cars, I purchased a "spare" one just for this purpose. You can get it from courtesyparts.com for just $77 plus shipping. One day, your MAF will fail hard so purchasing the spare one is not a waste of money.
I have two, surely both can't be faulty..
Old Sep 6, 2015 | 10:12 PM
  #14  
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Originally Posted by AT978
I have two, surely both can't be faulty..
If you are sure that your MAF is good, then it may be necessary to follow my suggestions in post #12 above.
Old Sep 6, 2015 | 10:31 PM
  #15  
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Originally Posted by maxiiiboy
It's difficult, and most mechanics can't do it as you need special tools that only dealers have. The simplest solution is to replace your MAF with another one (a good one, from a friend's car) and see what happens. Since the MAF is a common problem on our cars, I purchased a "spare" one just for this purpose. You can get it from courtesyparts.com for just $77 plus shipping. One day, your MAF will fail hard so purchasing the spare one is not a waste of money.
They don't need dealer equipment just to view data streams. Any number of scan tools will do just fine. If they want to reflash or install updates then they need a dealer level subscription.
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