maf mod
11-22-10, 03:21 PM
#3
I highly recommend that you don't put random parts from other cars on your vehicle without understanding exactly what it is changing.
The AFM from a supra could either be providing more or less fuel at any given RPM than stock, which means it could be hurting or helping...but how would you know which?
The AFM from a supra could either be providing more or less fuel at any given RPM than stock, which means it could be hurting or helping...but how would you know which?
11-22-10, 03:55 PM
#5
what car do you have? s4 or s5? na or turbo?
Actually this is great to see people experiment, FC scene is kind of dull and lacking with people who try different ****. So many people here are scared to go intake just because of what they hear about it. Just got to see some numbers with this mod.
I think the toyotas use a flap type like the s4 right? You wont benefit from just changing the maf unless you boost more imo.
Actually this is great to see people experiment, FC scene is kind of dull and lacking with people who try different ****. So many people here are scared to go intake just because of what they hear about it. Just got to see some numbers with this mod.
I think the toyotas use a flap type like the s4 right? You wont benefit from just changing the maf unless you boost more imo.
The following users liked this post:
Dirty_oil6 (05-04-20)
11-22-10, 04:45 PM
#7
Senior Member
Thread Starter
iTrader: (1)
Join Date: Apr 2010
Location: buffalo grove IL
Posts: 281
Likes: 0
Received 0 Likes
on
0 Posts
well i have a s4 and i thought about the damage it could cause that why i heavily premix and it wouldnt really damage the engine because of the omp is in perfect working condition and the extra premix. fyi it just plug in no modification to the harness or anything
Last edited by rx7fcfc; 11-22-10 at 04:48 PM.
Trending Topics
11-22-10, 05:42 PM
#8
Premixing extra oil isn't going to save your engine if it runs lean because you changed the AFM out. Before slapping random fuel control parts on the car, you should probably look up the voltage/resistance outputs for the MAF & compare them the stock AFM values. I can pretty much guarantee you it's different, and probably not in a good way.
The following users liked this post:
rlynchster (05-14-23)
11-22-10, 07:07 PM
#9
if it works well then more power to him. the AFM flapper door sensor was never a great design.. too bad FCs weren't tuned to use the stock MAP sensor or they would be years ahead of where we currently sit with flooding issues due to vacuum leaks and random hiccups. take a look at the FD for example, the only reason they flood is because of nonexistent compression, even starting one on one rotor isn't a difficult task.
11-22-10, 08:02 PM
#10
Moderator
iTrader: (3)
Join Date: Mar 2001
Location: https://www2.mazda.com/en/100th/
Posts: 30,802
Received 2,577 Likes
on
1,831 Posts
11-22-10, 10:16 PM
#14
If you go to the junk yard you will see a **** ton of cars with identical S4 style MAF's and a few with S5 style MAF's. Mazda does not make them. They are a general part just like many parts on the car. Each is designed for a specific motor/car. But the general style/design is all the same.
I am running the MAF from the RE right now on my S5 TII. Although it is from a similar motor...
I am running the MAF from the RE right now on my S5 TII. Although it is from a similar motor...
11-23-10, 10:21 AM
#17
some of you guys aren't getting the differences between these sensors so i will elaborate for you:
AFM(Air Flow Meter, stock on 2nd generation RX7's, all of them); a flapper door sensor that uses spring pressure on the flapper to measure the amount of air passing the door inside the AFM. it works but it is a bit crude, loss of spring tension over time will cause innacurate fuel delivery but they generally are fairly reliable in that respect. any vacuum leaks after the AFM will throw off the fuel delivery to the engine. the ECU uses pre-set tables to know how much fuel the engine needs at certain RPMs and AFM sensor readings, so a vacuum leak after the sensor will cause the flapper to not move enough(lean condition) and a boost leak will cause it to move too much as boost bleeds off after it has gone through(rich condition)
MAF(Mass Air Flow sensor, used on most '90 and newer imports and domestics); a hot wire vane sensor that looks like a flat brick of mesh with a sensor located in the middle. these supposedly offer less resistance than the flapper door sensor and so long as the sensor stays clean and oil free they will not lose accuracy. susceptible to the same issues as the AFM in vacuum/boost leak scenarios.
MAP(Manifold Absolute Pressure sensor, used on most all newer cars); generally the most reliable way to measure fuel delivery and efficient, there is no sensor in the intake tract blocking flow at all, just a sensor that measures boost and vacuum that runs off a vacuum port after the throttle body on the engine. the ECU uses the MAP sensor signal and engine RPMs to determine how much fuel the engine needs. this is a self calibrating system since it auto adjusts for changes in altitude and ambient atmospheric pressure. vacuum and boost leaks are already compensated for because the sensor is reading the true intake pressure/vacuum level with the leaks present. (it sure is nice when you blow a vacuum line off that the car doesn't stall in the middle of traffic)
AFM(Air Flow Meter, stock on 2nd generation RX7's, all of them); a flapper door sensor that uses spring pressure on the flapper to measure the amount of air passing the door inside the AFM. it works but it is a bit crude, loss of spring tension over time will cause innacurate fuel delivery but they generally are fairly reliable in that respect. any vacuum leaks after the AFM will throw off the fuel delivery to the engine. the ECU uses pre-set tables to know how much fuel the engine needs at certain RPMs and AFM sensor readings, so a vacuum leak after the sensor will cause the flapper to not move enough(lean condition) and a boost leak will cause it to move too much as boost bleeds off after it has gone through(rich condition)
MAF(Mass Air Flow sensor, used on most '90 and newer imports and domestics); a hot wire vane sensor that looks like a flat brick of mesh with a sensor located in the middle. these supposedly offer less resistance than the flapper door sensor and so long as the sensor stays clean and oil free they will not lose accuracy. susceptible to the same issues as the AFM in vacuum/boost leak scenarios.
MAP(Manifold Absolute Pressure sensor, used on most all newer cars); generally the most reliable way to measure fuel delivery and efficient, there is no sensor in the intake tract blocking flow at all, just a sensor that measures boost and vacuum that runs off a vacuum port after the throttle body on the engine. the ECU uses the MAP sensor signal and engine RPMs to determine how much fuel the engine needs. this is a self calibrating system since it auto adjusts for changes in altitude and ambient atmospheric pressure. vacuum and boost leaks are already compensated for because the sensor is reading the true intake pressure/vacuum level with the leaks present. (it sure is nice when you blow a vacuum line off that the car doesn't stall in the middle of traffic)
The following users liked this post:
diabolical1 (05-14-23)
11-23-10, 10:39 AM
#18
GNARKILL
Join Date: Nov 2009
Location: phoenix, az
Posts: 551
Likes: 0
Received 0 Likes
on
0 Posts
some of you guys aren't getting the differences between these sensors so i will elaborate for you:
AFM(Air Flow Meter, stock on 2nd generation RX7's, all of them); a flapper door sensor that uses spring pressure on the flapper to measure the amount of air passing the door inside the AFM. it works but it is a bit crude, loss of spring tension over time will cause innacurate fuel delivery but they generally are fairly reliable in that respect. any vacuum leaks after the AFM will throw off the fuel delivery to the engine. the ECU uses pre-set tables to know how much fuel the engine needs at certain RPMs and AFM sensor readings, so a vacuum leak after the sensor will cause the flapper to not move enough(lean condition) and a boost leak will cause it to move too much as boost bleeds off after it has gone through(rich condition)
MAF(Mass Air Flow sensor, used on most '90 and newer imports and domestics); a hot wire vane sensor that looks like a flat brick of mesh with a sensor located in the middle. these supposedly offer less resistance than the flapper door sensor and so long as the sensor stays clean and oil free they will not lose accuracy. susceptible to the same issues as the AFM in vacuum/boost leak scenarios.
MAP(Manifold Absolute Pressure sensor, used on most all newer cars); generally the most reliable way to measure fuel delivery and efficient, there is no sensor in the intake tract blocking flow at all, just a sensor that measures boost and vacuum that runs off a vacuum port after the throttle body on the engine. the ECU uses the MAP sensor signal and engine RPMs to determine how much fuel the engine needs. this is a self calibrating system since it auto adjusts for changes in altitude and ambient atmospheric pressure. vacuum and boost leaks are already compensated for because the sensor is reading the true intake pressure/vacuum level with the leaks present. (it sure is nice when you blow a vacuum line off that the car doesn't stall in the middle of traffic)
AFM(Air Flow Meter, stock on 2nd generation RX7's, all of them); a flapper door sensor that uses spring pressure on the flapper to measure the amount of air passing the door inside the AFM. it works but it is a bit crude, loss of spring tension over time will cause innacurate fuel delivery but they generally are fairly reliable in that respect. any vacuum leaks after the AFM will throw off the fuel delivery to the engine. the ECU uses pre-set tables to know how much fuel the engine needs at certain RPMs and AFM sensor readings, so a vacuum leak after the sensor will cause the flapper to not move enough(lean condition) and a boost leak will cause it to move too much as boost bleeds off after it has gone through(rich condition)
MAF(Mass Air Flow sensor, used on most '90 and newer imports and domestics); a hot wire vane sensor that looks like a flat brick of mesh with a sensor located in the middle. these supposedly offer less resistance than the flapper door sensor and so long as the sensor stays clean and oil free they will not lose accuracy. susceptible to the same issues as the AFM in vacuum/boost leak scenarios.
MAP(Manifold Absolute Pressure sensor, used on most all newer cars); generally the most reliable way to measure fuel delivery and efficient, there is no sensor in the intake tract blocking flow at all, just a sensor that measures boost and vacuum that runs off a vacuum port after the throttle body on the engine. the ECU uses the MAP sensor signal and engine RPMs to determine how much fuel the engine needs. this is a self calibrating system since it auto adjusts for changes in altitude and ambient atmospheric pressure. vacuum and boost leaks are already compensated for because the sensor is reading the true intake pressure/vacuum level with the leaks present. (it sure is nice when you blow a vacuum line off that the car doesn't stall in the middle of traffic)
as well as lots of other un molested rx7's?
11-23-10, 10:45 AM
#19
MECP Certified Installer
Airflow/pressure systems allow for more compensation when you mod the car, but are complicated and not really anymore accurate than a speed density system. The 3rd gen RX7's ran speed density, thus didn't require an AFM or MAF.
The SAFC can make our 2nd gen cars speed density and allow the removal of the AFM.
11-23-10, 10:51 AM
#20
the "pressure sensor" (MAP sensor in reality) is used to adjust the timing according to engine load. FCs also have a barometric pressure sensor located behind the passenger side right kick panel for altitude fuel adjustments. it is now, looking back, an overly complicated system with too many points for failure.
11-23-10, 10:56 AM
#21
GNARKILL
Join Date: Nov 2009
Location: phoenix, az
Posts: 551
Likes: 0
Received 0 Likes
on
0 Posts
thanks guys
to the OP, my s5 AFM needs replacing cause the spring is very very loose, and i have a 7MGTE MAF that works. instead of buying a new s5 afm id like to use what i got but do you get any negitive effects?? i understand it plugs right in but . . .
to the OP, my s5 AFM needs replacing cause the spring is very very loose, and i have a 7MGTE MAF that works. instead of buying a new s5 afm id like to use what i got but do you get any negitive effects?? i understand it plugs right in but . . .
11-23-10, 11:05 AM
#22
MECP Certified Installer
Don't want to blow your motor....
I've had my car dyno'd. Cost $100 and they throw a wide band on there temporarily, and take it off when done.
11-23-10, 02:02 PM
#23
Senior Member
Thread Starter
iTrader: (1)
Join Date: Apr 2010
Location: buffalo grove IL
Posts: 281
Likes: 0
Received 0 Likes
on
0 Posts
i have not check the spark plug yet but i will check them honestly i believe that by changing the maf with the supra maf i didnt do any damage because it did not notice any changes in the fuel economy or changes in the way the car smells or backfire therefore it not running to lean. on the plus side my car ran alot smoother and i can feel a tiny amount of power increase in the lower band. about 100 miles on it
11-23-10, 02:14 PM
#24
From random website on Toyota 22re AFM:
"The AFM mod involves cutting the silicone seal on the black cover to gain access. Once inside, there's a "curly brace" looking metal clip in the upper left corner being held down by a Phillip's screw. Mark with nail polish or similar, the original position of at least one of the ends. Then, WHILE HOLDING THE LARGE GEAR WHEEL, loosen the screw allowing the metal clip to go slack. Turn the gear wheel clockwise to lean the running mixture, and counter-clockwise for richer. The idle mixture is largely unaffected by this adjustment. Do not adjust any more than 3 teeth in either direction with a stock system. Once you have the gear wheel where you want it, tighten the Phillip's screw again to make the metal clip hold the wheel in place. Supposedly, a stock system shouldn't need any adjustment, and won't benefit much from changes. It's a trade-off; leaner helps off-the-line, richer adds to the top-end."
"To control the movement of this flap/aramture, the AFM is fitted with a flat-wound spring that is used to apply tension to the flap. This spring is held in place, and adjusted, via a plastic gear and a wire "holder". When this gear is tightened (turned clockwise) relative to the flat wound spring inside of it, it becomes harder for the door to open, and this translates to a leaner mixture (more air needs to flow in to move the door by a given amount, meaning theat the mixture is leaner relative to its starting point before adjustment). Turning the gear counter-clockwise has just the opposite effect, as the looser gear lets more air in relative to "stock".
Remember:
Turning the gear CLOCKWISE LEANS OUT THE MIXTURE.
Turning the gear COUNTER-CLOCKWISE RICHENS THE MIXTURE
Generally speaking, each tooth of the gear is equal to about a 2% change in the transient mixture (with stock injectors)."
http://www.flickr.com/photos/7118909...7594284969847/
The following users liked this post:
kenneth_ugalde (05-12-23)
11-23-10, 02:25 PM
#25
Senior Member
Thread Starter
iTrader: (1)
Join Date: Apr 2010
Location: buffalo grove IL
Posts: 281
Likes: 0
Received 0 Likes
on
0 Posts
A few of us RTEK guys are having a few issues with maxing the AFM airflow reading and are curious if we can get more fuel by Modding the S4 AFM... Anyone done this?
From random website on Toyota 22re AFM:
"The AFM mod involves cutting the silicone seal on the black cover to gain access. Once inside, there's a "curly brace" looking metal clip in the upper left corner being held down by a Phillip's screw. Mark with nail polish or similar, the original position of at least one of the ends. Then, WHILE HOLDING THE LARGE GEAR WHEEL, loosen the screw allowing the metal clip to go slack. Turn the gear wheel clockwise to lean the running mixture, and counter-clockwise for richer. The idle mixture is largely unaffected by this adjustment. Do not adjust any more than 3 teeth in either direction with a stock system. Once you have the gear wheel where you want it, tighten the Phillip's screw again to make the metal clip hold the wheel in place. Supposedly, a stock system shouldn't need any adjustment, and won't benefit much from changes. It's a trade-off; leaner helps off-the-line, richer adds to the top-end."
"To control the movement of this flap/aramture, the AFM is fitted with a flat-wound spring that is used to apply tension to the flap. This spring is held in place, and adjusted, via a plastic gear and a wire "holder". When this gear is tightened (turned clockwise) relative to the flat wound spring inside of it, it becomes harder for the door to open, and this translates to a leaner mixture (more air needs to flow in to move the door by a given amount, meaning theat the mixture is leaner relative to its starting point before adjustment). Turning the gear counter-clockwise has just the opposite effect, as the looser gear lets more air in relative to "stock".
Remember:
Turning the gear CLOCKWISE LEANS OUT THE MIXTURE.
Turning the gear COUNTER-CLOCKWISE RICHENS THE MIXTURE
Generally speaking, each tooth of the gear is equal to about a 2% change in the transient mixture (with stock injectors)."
http://www.flickr.com/photos/7118909...7594284969847/
From random website on Toyota 22re AFM:
"The AFM mod involves cutting the silicone seal on the black cover to gain access. Once inside, there's a "curly brace" looking metal clip in the upper left corner being held down by a Phillip's screw. Mark with nail polish or similar, the original position of at least one of the ends. Then, WHILE HOLDING THE LARGE GEAR WHEEL, loosen the screw allowing the metal clip to go slack. Turn the gear wheel clockwise to lean the running mixture, and counter-clockwise for richer. The idle mixture is largely unaffected by this adjustment. Do not adjust any more than 3 teeth in either direction with a stock system. Once you have the gear wheel where you want it, tighten the Phillip's screw again to make the metal clip hold the wheel in place. Supposedly, a stock system shouldn't need any adjustment, and won't benefit much from changes. It's a trade-off; leaner helps off-the-line, richer adds to the top-end."
"To control the movement of this flap/aramture, the AFM is fitted with a flat-wound spring that is used to apply tension to the flap. This spring is held in place, and adjusted, via a plastic gear and a wire "holder". When this gear is tightened (turned clockwise) relative to the flat wound spring inside of it, it becomes harder for the door to open, and this translates to a leaner mixture (more air needs to flow in to move the door by a given amount, meaning theat the mixture is leaner relative to its starting point before adjustment). Turning the gear counter-clockwise has just the opposite effect, as the looser gear lets more air in relative to "stock".
Remember:
Turning the gear CLOCKWISE LEANS OUT THE MIXTURE.
Turning the gear COUNTER-CLOCKWISE RICHENS THE MIXTURE
Generally speaking, each tooth of the gear is equal to about a 2% change in the transient mixture (with stock injectors)."
http://www.flickr.com/photos/7118909...7594284969847/
