Direct Injection Question
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From: Thunder Bay
Direct Injection Question
So, i know that the black stuff coming out of my exhaust is because of the direct injection and so is the engine tick. I was just wondering why it poofs black? Does that mean its burning too much fuel? And what is the tick, i remember reading something about it but i forget where.
Thanks
Thanks
rich to a point is conservative - and will avoid some problems...
GMS1 for example is still rich ~ but a bit leaner than stock...
don't be fooled by mis-reading AFR's ~ if the engine doesn't go rich when gunning it ~ then something is wrong... but for constant/steady speeds you won't see that (or your AFR setuip is probably goobered)
GMS1 for example is still rich ~ but a bit leaner than stock...
don't be fooled by mis-reading AFR's ~ if the engine doesn't go rich when gunning it ~ then something is wrong... but for constant/steady speeds you won't see that (or your AFR setuip is probably goobered)
rich to a point is conservative - and will avoid some problems...
GMS1 for example is still rich ~ but a bit leaner than stock...
don't be fooled by mis-reading AFR's ~ if the engine doesn't go rich when gunning it ~ then something is wrong... but for constant/steady speeds you won't see that (or your AFR setuip is probably goobered)
GMS1 for example is still rich ~ but a bit leaner than stock...
don't be fooled by mis-reading AFR's ~ if the engine doesn't go rich when gunning it ~ then something is wrong... but for constant/steady speeds you won't see that (or your AFR setuip is probably goobered)
I digress, especially in this context the terms lean or rich are kinda subjective...
GM will not make a very lean setup...
But it won't be too rich either.
IF it was very lean your AFR (assuming it's working properly) would be sticking VERY close to 14 or numerically higher...
(14 is an ideal/generic number)
GM will not make a very lean setup...
But it won't be too rich either.
IF it was very lean your AFR (assuming it's working properly) would be sticking VERY close to 14 or numerically higher...
(14 is an ideal/generic number)
I digress, especially in this context the terms lean or rich are kinda subjective...
GM will not make a very lean setup...
But it won't be too rich either.
IF it was very lean your AFR (assuming it's working properly) would be sticking VERY close to 14 or numerically higher...
(14 is an ideal/generic number)
GM will not make a very lean setup...
But it won't be too rich either.
IF it was very lean your AFR (assuming it's working properly) would be sticking VERY close to 14 or numerically higher...
(14 is an ideal/generic number)
Senior Member
Joined: 06-22-09
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From: Kathmandu
I digress, especially in this context the terms lean or rich are kinda subjective...
GM will not make a very lean setup...
But it won't be too rich either.
IF it was very lean your AFR (assuming it's working properly) would be sticking VERY close to 14 or numerically higher...
(14 is an ideal/generic number)
GM will not make a very lean setup...
But it won't be too rich either.
IF it was very lean your AFR (assuming it's working properly) would be sticking VERY close to 14 or numerically higher...
(14 is an ideal/generic number)
ok guys, did you read the OP's initial post?
I came here just to try to help ~ a part of which is sharing some information I've picked up...
there is nothing about me that should in any way "scare" anyone.
I never said I know everything, and I wasn't attempting to suggest that I'm always correct.
It seems apparent that people who might know more than me have come in, and found fault with my post(s) ~ when in fact the initial question to which I replied was about black smoke on a stock car.
Sorry if I posted in any fashion which would lead anyone to believe that I believe myself to be any kind of know-all, end all.
fair enough?
I came here just to try to help ~ a part of which is sharing some information I've picked up...
there is nothing about me that should in any way "scare" anyone.
I never said I know everything, and I wasn't attempting to suggest that I'm always correct.
It seems apparent that people who might know more than me have come in, and found fault with my post(s) ~ when in fact the initial question to which I replied was about black smoke on a stock car.
Sorry if I posted in any fashion which would lead anyone to believe that I believe myself to be any kind of know-all, end all.
fair enough?
My car drops to about 12.4 at wot and around 14.6 cruising. I have the poof of black when I get on it a little after babying it for a while. If it was doing it every time I touched it I would be getting worried lol
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New Member
Joined: 12-26-11
Posts: 135
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From: Thunder Bay
I just got my car and have it parked for the winter. I start it about every week or so. Since there is snow on the ground when i start it i see what comes out of the exhaust on the snow. Its not too bad and it doesn't actually "poof black" (sorry thats what we call it when our diesels roll coal) just theres a bit of black on the snow. is that okay since the fact i start it every week or two?
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Joined: 02-09-09
Posts: 4,374
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From: Tejas
I think some of y'all are getting confused on the whole rich AFR thing.
This car sticks to ~14.6-14.7 AFR at idle and many driving conditions. This is considered Stoichimetric, and is neither rich nor lean. That means that when combustion occurs, all of the fuel has reacted with all of the gasoline, and there is nothing left of either to react. Rich means there was too much gasoline compared to air, and there was gasoline left over, and lean means the opposite.
Under wide open throttle, for safety and power, the AFR richen up and will drop to a lower AFR value, depending on the tune or car.
That being said the term "rich" can be confusing, since it's an ambiguous term (being relative).
For instance, 14.7 AFR technically is neither rich or lean from a chemistry standpoint because it is the perfect chemical reaction balance for gasoline, but it would also be way too lean in a WOT circumstance. Conversely going with a lower AFR is considered rich from a chemistry standpoint (because there would be gasoline left over after the reaction with the air), but may be spot-on for WOT use.
This car sticks to ~14.6-14.7 AFR at idle and many driving conditions. This is considered Stoichimetric, and is neither rich nor lean. That means that when combustion occurs, all of the fuel has reacted with all of the gasoline, and there is nothing left of either to react. Rich means there was too much gasoline compared to air, and there was gasoline left over, and lean means the opposite.
Under wide open throttle, for safety and power, the AFR richen up and will drop to a lower AFR value, depending on the tune or car.
That being said the term "rich" can be confusing, since it's an ambiguous term (being relative).
For instance, 14.7 AFR technically is neither rich or lean from a chemistry standpoint because it is the perfect chemical reaction balance for gasoline, but it would also be way too lean in a WOT circumstance. Conversely going with a lower AFR is considered rich from a chemistry standpoint (because there would be gasoline left over after the reaction with the air), but may be spot-on for WOT use.
I think some of y'all are getting confused on the whole rich AFR thing.
This car sticks to ~14.6-14.7 AFR at idle and many driving conditions. This is considered Stoichimetric, and is neither rich nor lean. That means that when combustion occurs, all of the fuel has reacted with all of the gasoline, and there is nothing left of either to react. Rich means there was too much gasoline compared to air, and there was gasoline left over, and lean means the opposite.
Under wide open throttle, for safety and power, the AFR richen up and will drop to a lower AFR value, depending on the tune or car.
That being said the term "rich" can be confusing, since it's an ambiguous term (being relative).
For instance, 14.7 AFR technically is neither rich or lean from a chemistry standpoint because it is the perfect chemical reaction balance for gasoline, but it would also be way too lean in a WOT circumstance. Conversely going with a lower AFR is considered rich from a chemistry standpoint (because there would be gasoline left over after the reaction with the air), but may be spot-on for WOT use.
This car sticks to ~14.6-14.7 AFR at idle and many driving conditions. This is considered Stoichimetric, and is neither rich nor lean. That means that when combustion occurs, all of the fuel has reacted with all of the gasoline, and there is nothing left of either to react. Rich means there was too much gasoline compared to air, and there was gasoline left over, and lean means the opposite.
Under wide open throttle, for safety and power, the AFR richen up and will drop to a lower AFR value, depending on the tune or car.
That being said the term "rich" can be confusing, since it's an ambiguous term (being relative).
For instance, 14.7 AFR technically is neither rich or lean from a chemistry standpoint because it is the perfect chemical reaction balance for gasoline, but it would also be way too lean in a WOT circumstance. Conversely going with a lower AFR is considered rich from a chemistry standpoint (because there would be gasoline left over after the reaction with the air), but may be spot-on for WOT use.
I think some of y'all are getting confused on the whole rich AFR thing.
This car sticks to ~14.6-14.7 AFR at idle and many driving conditions. This is considered Stoichimetric, and is neither rich nor lean. That means that when combustion occurs, all of the fuel has reacted with all of the gasoline, and there is nothing left of either to react. Rich means there was too much gasoline compared to air, and there was gasoline left over, and lean means the opposite.
Under wide open throttle, for safety and power, the AFR richen up and will drop to a lower AFR value, depending on the tune or car.
That being said the term "rich" can be confusing, since it's an ambiguous term (being relative).
For instance, 14.7 AFR technically is neither rich or lean from a chemistry standpoint because it is the perfect chemical reaction balance for gasoline, but it would also be way too lean in a WOT circumstance. Conversely going with a lower AFR is considered rich from a chemistry standpoint (because there would be gasoline left over after the reaction with the air), but may be spot-on for WOT use.
This car sticks to ~14.6-14.7 AFR at idle and many driving conditions. This is considered Stoichimetric, and is neither rich nor lean. That means that when combustion occurs, all of the fuel has reacted with all of the gasoline, and there is nothing left of either to react. Rich means there was too much gasoline compared to air, and there was gasoline left over, and lean means the opposite.
Under wide open throttle, for safety and power, the AFR richen up and will drop to a lower AFR value, depending on the tune or car.
That being said the term "rich" can be confusing, since it's an ambiguous term (being relative).
For instance, 14.7 AFR technically is neither rich or lean from a chemistry standpoint because it is the perfect chemical reaction balance for gasoline, but it would also be way too lean in a WOT circumstance. Conversely going with a lower AFR is considered rich from a chemistry standpoint (because there would be gasoline left over after the reaction with the air), but may be spot-on for WOT use.
The reason you cant just make the car too rich vs meth injection is you will end up with a hydrolock event with gas.
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Joined: 06-22-09
Posts: 5,989
Likes: 7
From: Kathmandu
ok guys, did you read the OP's initial post?
I came here just to try to help ~ a part of which is sharing some information I've picked up...
there is nothing about me that should in any way "scare" anyone.
I never said I know everything, and I wasn't attempting to suggest that I'm always correct.
It seems apparent that people who might know more than me have come in, and found fault with my post(s) ~ when in fact the initial question to which I replied was about black smoke on a stock car.
Sorry if I posted in any fashion which would lead anyone to believe that I believe myself to be any kind of know-all, end all.
fair enough?
I came here just to try to help ~ a part of which is sharing some information I've picked up...
there is nothing about me that should in any way "scare" anyone.
I never said I know everything, and I wasn't attempting to suggest that I'm always correct.
It seems apparent that people who might know more than me have come in, and found fault with my post(s) ~ when in fact the initial question to which I replied was about black smoke on a stock car.
Sorry if I posted in any fashion which would lead anyone to believe that I believe myself to be any kind of know-all, end all.
fair enough?
Senior Member
Joined: 02-09-09
Posts: 4,374
Likes: 5
From: Tejas
Correction: Going wide open throttle, 14.7 AFR is still neutral (niether rich nor lean) BUT it is not the safest to prevent the engine from heating up to quickly and eventually causing detonation before the piston travel is at its max. The car goes rich during WOT to keep the engine cool using the unburnt gas as "meth+water mix" does for meth injection in a sense. Also it pulls built heat from the turbo too.
The reason you cant just make the car too rich vs meth injection is you will end up with a hydrolock event with gas.
The reason you cant just make the car too rich vs meth injection is you will end up with a hydrolock event with gas.
Here's an old post of mine from a while back that explains it a bit more, with relation to fuel trims and stuff too:
AFR: Air-Fuel Ratio. This is the ratio of molecules of air to molecules of fuel. At about 14.7, the mixture is said to be stoichiometric ("stoich"), and is the point where all the air molecules will react with all the fuel molecules. If there is more fuel than air (<14.7), then the mixture is said to be "rich". If there is more air than fuel (>14.7), then the mixture is said to be "lean". There are advantages and disadvantages to being rich, stoich, or lean. Typical car engines usually run stoich for normal operation, rich for warm-up and full throttle, and lean for long cruising to save gas. *Note: 14.7 is stoich for gasoline. Other fuels, such as E85, require a different ratio to be stoich due to their different chemical makeup (about 9.76 in the case of E85).
Lambda: This is the Air-Fuel Ratio expressed as a quotient, when stoich is the divisor. For example, if you're running at 13.0 AFR, then that would be about 0.88 (13.0/14.7). Some applications, such as tuning for the LNF, are programmed instead in Lambda.
STFT: Short Term Fuel Trim. This is the amount of fuel that the engine computer adds or subtracts to maintain the desired AFR. It is usually expressed as a positive or negative number representing a percentage. The STFT is updated and tweaked very quickly by the engine computer. Intakes and other factors can cause the Mass AirFlow sensor (MAF) to mis-read the amount of air going past it into the engine. The engine computer also uses STFT to help compensate for this.
LTFT: Long Term Fuel Trim. This is the amount of fuel that the engine computer adds or subtracts over time to maintain the desired AFR.
The engine computer looks at both STFT and LTFT when deciding how much fuel to mix with the air it takes in. It then sees how close it got to what it was wanting and re-adjusts the STFT and later LTFT again. This adjust-feedback-adjust approach the engine computer uses when the engine is in normal operation is called "closed loop".
Lambda: This is the Air-Fuel Ratio expressed as a quotient, when stoich is the divisor. For example, if you're running at 13.0 AFR, then that would be about 0.88 (13.0/14.7). Some applications, such as tuning for the LNF, are programmed instead in Lambda.
STFT: Short Term Fuel Trim. This is the amount of fuel that the engine computer adds or subtracts to maintain the desired AFR. It is usually expressed as a positive or negative number representing a percentage. The STFT is updated and tweaked very quickly by the engine computer. Intakes and other factors can cause the Mass AirFlow sensor (MAF) to mis-read the amount of air going past it into the engine. The engine computer also uses STFT to help compensate for this.
LTFT: Long Term Fuel Trim. This is the amount of fuel that the engine computer adds or subtracts over time to maintain the desired AFR.
The engine computer looks at both STFT and LTFT when deciding how much fuel to mix with the air it takes in. It then sees how close it got to what it was wanting and re-adjusts the STFT and later LTFT again. This adjust-feedback-adjust approach the engine computer uses when the engine is in normal operation is called "closed loop".
I always get corrected no matter what even if I proof read something before clicking the post button. I wanted to try it
Senior Member
Joined: 02-09-09
Posts: 4,374
Likes: 5
From: Tejas
So, i know that the black stuff coming out of my exhaust is because of the direct injection and so is the engine tick. I was just wondering why it poofs black? Does that mean its burning too much fuel? And what is the tick, i remember reading something about it but i forget where.
Thanks
Thanks