Chrysler to continue using MAP sensors
- Thread starter StevieC
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It's not relying on the default fuel tables at WOT, though. It's using the fuel tables it built based on feedback from the o2 sensor.
Right, I agreed the closed looped fuel trimming of the tables add some accuracy over fixed fuel tables even for open loop. But that isn't the primary purpose of closed loop. The open loop WOT principle is the same as N-alpha. I think during open loop power enrichment, the A/F ratio only has to be "close" enough in enrichment as opposed to exact, same way with cold start/warm up.
you'd be surprised how well the speed/density system can adjust the fuel trim. It just requires a few key cycles, not as quick but still very precise.
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MAF is a restriction in the intake which can be an issue for some big breathers. And Speed/density is very easy to tinker with the tables and custom tune.
That's funny considering Chrysler's heaviest breather, the 8.4L V10 in the Viper, uses MAF sensors.
MAF is a restriction in the intake which can be an issue for some big breathers. And Speed/density is very easy to tinker with the tables and custom tune.
That's funny considering Chrysler's heaviest breather, the 8.4L V10 in the Viper, uses MAF sensors.
Yeah speed density probably is about as precise in closed loop. Plus the MAP monitors engine vacuum. It seems to work for Chrysler. And like Brian mentioned the LTFT adds some precision for open loop too.
What I was getting at is it is mostly for emissions. You can reset the PCM on your 100k+ mile car and it runs fine. Throw in a broadband O2 sensor and you could have feedback for best lean economy and for power enrichment. Isn't that what they do in Europe?
What I was getting at is it is mostly for emissions. You can reset the PCM on your 100k+ mile car and it runs fine. Throw in a broadband O2 sensor and you could have feedback for best lean economy and for power enrichment. Isn't that what they do in Europe?
I kinda like that MAP's are still in use because as the engine ages and looses compression the vacuum changes and this keeps the fuel mixture "Honest" and IMO more in line with emission standards!
Nothing wrong with MAP sensor (speed density also known as) setup as it gets the job done. It's just not as accurate as a MAF setup. GM uses both in most applications and has for a long time (my older 1994 Corvette even uses both as does our 2011 trucks). The MAF is the main system and the MAP is a backup. Two are better than one I suppose.
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Sure GM can sell more parts that way seeing as they always need something replaced... (Some models excluded)
Originally Posted By: StevieC
Sure GM can sell more parts that way seeing as they always need something replaced... (Some models excluded)
I see that not only are you back but you're the same StevieC. I've been good to you so far in case you haven't noticed than you go and pull that [censored]....
Sure GM can sell more parts that way seeing as they always need something replaced... (Some models excluded)
I see that not only are you back but you're the same StevieC. I've been good to you so far in case you haven't noticed than you go and pull that [censored]....
Cry about it... It's an opinion... You are entitled to yours and I'm entitled to mine...
Originally Posted By: GMBoy
Nothing wrong with MAP sensor (speed density also known as) setup as it gets the job done. It's just not as accurate as a MAF setup. GM uses both in most applications and has for a long time (my older 1994 Corvette even uses both as does our 2011 trucks). The MAF is the main system and the MAP is a backup. Two are better than one I suppose.
They use both b/c MAP handles quick changes better. MAF relies on the temp swing of the sensing element, so it takes a cpl hundred milliseconds or so to keep up, whereas MAP sees the immediate change.
So-- MAP gets the transients, MAF fine-tunes....
M
Nothing wrong with MAP sensor (speed density also known as) setup as it gets the job done. It's just not as accurate as a MAF setup. GM uses both in most applications and has for a long time (my older 1994 Corvette even uses both as does our 2011 trucks). The MAF is the main system and the MAP is a backup. Two are better than one I suppose.
They use both b/c MAP handles quick changes better. MAF relies on the temp swing of the sensing element, so it takes a cpl hundred milliseconds or so to keep up, whereas MAP sees the immediate change.
So-- MAP gets the transients, MAF fine-tunes....
M
Originally Posted By: GMBoy
Originally Posted By: StevieC
Cry about it... It's an opinion... You are entitled to yours and I'm entitled to mine...
Oh wow. I can see we're gonna have fun.
You are just upset because I'm posting something against your opinion about GM.
Grow a set and leave it at that... You don't need to defend your beloved GM. Let their own actions in the real world be a testament to the brand instead of the ones that are blinded by the light such as you and some others on here.
With that said I'm not wasting any more effort or time with you and your posts.
Good day to you sir!
Originally Posted By: StevieC
Cry about it... It's an opinion... You are entitled to yours and I'm entitled to mine...
Oh wow. I can see we're gonna have fun.
You are just upset because I'm posting something against your opinion about GM.
Grow a set and leave it at that... You don't need to defend your beloved GM. Let their own actions in the real world be a testament to the brand instead of the ones that are blinded by the light such as you and some others on here.
With that said I'm not wasting any more effort or time with you and your posts.
Good day to you sir!
Originally Posted By: StevieC
You are just upset because I'm posting something against your opinion about GM.
Grow a set and leave it at that... You don't need to defend your beloved GM. Let their own actions in the real world be a testament to the brand instead of the ones that are blinded by the light such as you and some others on here.
With that said I'm not wasting any more effort or time with you and your posts.
Good day to you sir!
I don't have anything against either of you, and I certainly don't care to wade into whatever cod-swinging competition you two have going on. However, it seems your comments could be bounced right back at you for your GM bashing. If you're not bringing any new information or valuable insight to the table, your posts are at least as useless as his.
You are just upset because I'm posting something against your opinion about GM.
Grow a set and leave it at that... You don't need to defend your beloved GM. Let their own actions in the real world be a testament to the brand instead of the ones that are blinded by the light such as you and some others on here.
With that said I'm not wasting any more effort or time with you and your posts.
Good day to you sir!
I don't have anything against either of you, and I certainly don't care to wade into whatever cod-swinging competition you two have going on. However, it seems your comments could be bounced right back at you for your GM bashing. If you're not bringing any new information or valuable insight to the table, your posts are at least as useless as his.
so true.
That said, speed/density is VERY precise when in closed loop, and is just as good as any MAF setup on the road today.
The only advantage MAF has is tune-ability for modding.
That said, speed/density is VERY precise when in closed loop, and is just as good as any MAF setup on the road today.
The only advantage MAF has is tune-ability for modding.
Originally Posted By: StevieC
Originally Posted By: GMBoy
Originally Posted By: StevieC
Cry about it... It's an opinion... You are entitled to yours and I'm entitled to mine...
Oh wow. I can see we're gonna have fun.
You are just upset because I'm posting something against your opinion about GM.
Grow a set and leave it at that... You don't need to defend your beloved GM. Let their own actions in the real world be a testament to the brand instead of the ones that are blinded by the light such as you and some others on here.
With that said I'm not wasting any more effort or time with you and your posts.
Good day to you sir!
No my friend I respect your opinion - always did - thought we ironed that out last year. You just added something to the thread that was not value added to the poster. I am very open minded about autos and PLENTY on here know this. I am not "only GM" and brainwashed as you say. I have cursed GM on here plenty often! I call it as I see it - GM or not.
I do have "a set" and use them for women...
AS far as GM's actions - they are proving themselves with great new products (so is Ford) and sales, etc. Nothing happens overnight but the last 5 years have been paramount for GM.
I don't know why your panties are in such a bunch are you that thin skinned. C'mon man - we always had fun BEFORE you left here and now that you come back you seem different.
Now share a beer with me...and let's move on
Originally Posted By: GMBoy
Originally Posted By: StevieC
Cry about it... It's an opinion... You are entitled to yours and I'm entitled to mine...
Oh wow. I can see we're gonna have fun.
You are just upset because I'm posting something against your opinion about GM.
Grow a set and leave it at that... You don't need to defend your beloved GM. Let their own actions in the real world be a testament to the brand instead of the ones that are blinded by the light such as you and some others on here.
With that said I'm not wasting any more effort or time with you and your posts.
Good day to you sir!
No my friend I respect your opinion - always did - thought we ironed that out last year. You just added something to the thread that was not value added to the poster. I am very open minded about autos and PLENTY on here know this. I am not "only GM" and brainwashed as you say. I have cursed GM on here plenty often! I call it as I see it - GM or not.
I do have "a set" and use them for women...
AS far as GM's actions - they are proving themselves with great new products (so is Ford) and sales, etc. Nothing happens overnight but the last 5 years have been paramount for GM.
I don't know why your panties are in such a bunch are you that thin skinned. C'mon man - we always had fun BEFORE you left here and now that you come back you seem different.
Now share a beer with me...and let's move on
Originally Posted By: meep
Originally Posted By: GMBoy
Nothing wrong with MAP sensor (speed density also known as) setup as it gets the job done. It's just not as accurate as a MAF setup. GM uses both in most applications and has for a long time (my older 1994 Corvette even uses both as does our 2011 trucks). The MAF is the main system and the MAP is a backup. Two are better than one I suppose.
They use both b/c MAP handles quick changes better. MAF relies on the temp swing of the sensing element, so it takes a cpl hundred milliseconds or so to keep up, whereas MAP sees the immediate change.
So-- MAP gets the transients, MAF fine-tunes....
M
Excellent description!
Originally Posted By: GMBoy
Nothing wrong with MAP sensor (speed density also known as) setup as it gets the job done. It's just not as accurate as a MAF setup. GM uses both in most applications and has for a long time (my older 1994 Corvette even uses both as does our 2011 trucks). The MAF is the main system and the MAP is a backup. Two are better than one I suppose.
They use both b/c MAP handles quick changes better. MAF relies on the temp swing of the sensing element, so it takes a cpl hundred milliseconds or so to keep up, whereas MAP sees the immediate change.
So-- MAP gets the transients, MAF fine-tunes....
M
Excellent description!
I think that throttle position sensor in conjunction with a MAF more than compensates for the slower response of a MAF.
At least it does on Ford vehicles, which have used MAF setups exclusively for about 15 years now. The newer Ford vehicles which use a MAF also do not have a BAP (baro) sensor. Some of the old ones did have both a MAF and a BAP sensor, but they now use the MAF readings to calculate a BARO reading. (I've never seen any documentation as to how this is done).
The BARO reading on these Ford vehicles can be used to determine if the MAF is reading correctly. An incorrect BARO reading is an indication that the MAF is not right.
At least it does on Ford vehicles, which have used MAF setups exclusively for about 15 years now. The newer Ford vehicles which use a MAF also do not have a BAP (baro) sensor. Some of the old ones did have both a MAF and a BAP sensor, but they now use the MAF readings to calculate a BARO reading. (I've never seen any documentation as to how this is done).
The BARO reading on these Ford vehicles can be used to determine if the MAF is reading correctly. An incorrect BARO reading is an indication that the MAF is not right.
GM Boy,
I just like getting your blood boiling... Relax, I said it jokingly.
No company in their right mind (even if GM isn't in theirs) is going to include more sensors just for the sake of selling more parts.
It doesn't make sense from a cost perspective.
I will have!
I just like getting your blood boiling... Relax, I said it jokingly.
No company in their right mind (even if GM isn't in theirs) is going to include more sensors just for the sake of selling more parts.
It doesn't make sense from a cost perspective.
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