i have my mbc off the wastegate line only thing connected in it. I have my boost guage and afc connected into the brake booster line after the check valve. try that i saw a post about what line to use the other day and pics. So do you think my theory is correct on the afc? John where you at man lets get this fixed my dam car is getting worse everyday. Ill run some more test this week with the scan tool to get a/f and 02 sensor readings off the mazda computer.
You are using an out of date browser. It may not display this or other websites correctly.
You should upgrade or use an alternative browser.
You should upgrade or use an alternative browser.
*HELP*DSM afc related
- Thread starter tallrd
- Start date
ZMN BY U said:bump john.............answer please lets get some more info
if your problem is from the ECU learning around the DSM it should be able to be fixed short term by resetting the ECU. Pull the negative battery cable and step on the brake pedal until the tail lights stop lighting up. Wait a few awhile and hook the battery back up. If the problem is caused by the ECU adjusting for the DSM it should go away for awhile unitl it relearns. This would prove that the ECU/DSM are not getting along. If you still have a bad idle then something else is going on with your car.
DSMConvert
AWD...say Bye Bye
- :
- Titanium MS6
ok talked with techs, ran some testing and such, hence the delays.....the o2 sensors in these cars are heated o2 sensors...the fact that the problem only persists until the car warms up indicates that its a problem with the 02 sensors...this is confirmed by mazda techs at 2 local dealerships here. Not saying the o2 sensors are bad, just saying they are taking longer than usual to heat up to operating temps, this is where the ecu is having issues, b/c its not getting accurate readings from the 02 sensor, so it goes back to its long and short term fuel trims to figure out what its supposed to do fuel wise. In colder climates this will produce a leaner condition, while in warmer climates this will produce a richer condition (generally speaking). Now the solution is to make the afc active all the time so that the ecu never tries to go to its preprogrammed map settings....like i said earlier the ecu isnt learning around the afc, its becoming completely dependant on it. Not a big deal, BUT what I need is some accurate idle o2 readings so I can make the map. More than likely I will have a lean idle map and a rich idle map once i get some readings to go by...Just so we dont get confused I am referring to the 1st o2 sensor, this is the one that controlls everything...the one behind the cat is for all intensive purposes useless and is only there to assure emissions functionality. On another note for those of you with over 20K on your cars if you have never pulled your 1st o2 sensor I highly suggest you do so. A. you'll see just how rich your car was running, and B. cleaning it with brake parts cleaner will give you better readings and quicker heat up sessions at idle.
this is great advice re the o2 sensor. I'll talk to you 1 on 1 about my vac source issue as soon I have your #. thanks!
DSMConvert said:ok talked with techs, ran some testing and such, hence the delays.....the o2 sensors in these cars are heated o2 sensors...the fact that the problem only persists until the car warms up indicates that its a problem with the 02 sensors...this is confirmed by mazda techs at 2 local dealerships here. Not saying the o2 sensors are bad, just saying they are taking longer than usual to heat up to operating temps, this is where the ecu is having issues, b/c its not getting accurate readings from the 02 sensor, so it goes back to its long and short term fuel trims to figure out what its supposed to do fuel wise. In colder climates this will produce a leaner condition, while in warmer climates this will produce a richer condition (generally speaking). Now the solution is to make the afc active all the time so that the ecu never tries to go to its preprogrammed map settings....like i said earlier the ecu isnt learning around the afc, its becoming completely dependant on it. Not a big deal, BUT what I need is some accurate idle o2 readings so I can make the map. More than likely I will have a lean idle map and a rich idle map once i get some readings to go by...Just so we dont get confused I am referring to the 1st o2 sensor, this is the one that controlls everything...the one behind the cat is for all intensive purposes useless and is only there to assure emissions functionality. On another note for those of you with over 20K on your cars if you have never pulled your 1st o2 sensor I highly suggest you do so. A. you'll see just how rich your car was running, and B. cleaning it with brake parts cleaner will give you better readings and quicker heat up sessions at idle.
John i agree i did try the exhaust 02 sensor first but it didnt fix it so your right its the one on the motor. I will try to get some 02 sensor readings this week in our shop like i said i do work for mazda im a service advisor. I was waiting to see your answer before i commented but i think your right my guys say the same thing 02 sensor has to warm up before it reads correctly. Also i think because of the added richness the 02 sensor is being fould like a plug you see it took a few months before this happend to my car so i guess the added fuel build up on the 02 sensor has now reached a point of it being a problem. So i do agree ill try replacing the 02 sensor and see if it helps. But if you read my post on when mine does this its only after i boost and drive for over a few miles then stop for a few minuites then start the car up and it gives me a rough idle. Ive done everything to this car cleaned throttle body out egr, all of the steps to fix it but it hasnt worked so lets see if i can get some 02 readings while its rough idle is happening. But i still think the ecu is learning the afc is hooked up. thanks fore working with me and others on the issue i hope with our resources we can get an accurate solution.
thanks again, troy
thanks again, troy
OK everyone, I got some info you guys might want to hear. I got my zeitronix wideband hooked up, and was datalogging some signals.
I found out that the AFC alters your O2 signal even during vacuum. It sends out a sine wave to trick the car into thinking it is at 14.7. This basically puts the car into open loop all the time. It is no wonder the car could not idle properly like this.
I think there are a couple solutions to this.
1. Disconnect the O2 wire from the AFC, and reconnect the two ends normally. If my theory is correct, then this will still allow the AFC to do it's thing when the car is in open loop (WOT for example), and let the car do it's thing during idle and light throttle.
2. There is a setting under the "Output Settings" menu, called Output B. On my unit it came set to "Over Pressure", and below that, the pressure value was set to -18.12. I think if you were to set this to something like 0, then the AFC would not do any O2 sensor trickery until you are actually in boost. Alternatively it looks like you can set this to also switch by rpm if you wanted.
*Note: I couldn't tell how you are supposed to load this setting onto the AFC, if writing the fuel map to it does it, or if the Reset ECU button is necessary. If you reset it, you should have to write the fuel map again.
For now I have disconnected my AFC. I'm not sure when or if I'll reinstall it. But you guys can give this a try and see if this helps. I did try #1 briefly, and my idle worked well like this. I'm not completely sure if this disables the AFC too much, but I think it should still work only when the car is in open loop(which seems like the ideal situation anyways).
As for option #2 I did not try this, but here is a correspondence I had with a Spit Second rep which was a little vague to me, but I think this confirms my thoughts:
I found out that the AFC alters your O2 signal even during vacuum. It sends out a sine wave to trick the car into thinking it is at 14.7. This basically puts the car into open loop all the time. It is no wonder the car could not idle properly like this.
I think there are a couple solutions to this.
1. Disconnect the O2 wire from the AFC, and reconnect the two ends normally. If my theory is correct, then this will still allow the AFC to do it's thing when the car is in open loop (WOT for example), and let the car do it's thing during idle and light throttle.
2. There is a setting under the "Output Settings" menu, called Output B. On my unit it came set to "Over Pressure", and below that, the pressure value was set to -18.12. I think if you were to set this to something like 0, then the AFC would not do any O2 sensor trickery until you are actually in boost. Alternatively it looks like you can set this to also switch by rpm if you wanted.
*Note: I couldn't tell how you are supposed to load this setting onto the AFC, if writing the fuel map to it does it, or if the Reset ECU button is necessary. If you reset it, you should have to write the fuel map again.
For now I have disconnected my AFC. I'm not sure when or if I'll reinstall it. But you guys can give this a try and see if this helps. I did try #1 briefly, and my idle worked well like this. I'm not completely sure if this disables the AFC too much, but I think it should still work only when the car is in open loop(which seems like the ideal situation anyways).
As for option #2 I did not try this, but here is a correspondence I had with a Spit Second rep which was a little vague to me, but I think this confirms my thoughts:
Peepsalot said:In the documentation that came with my PSC1, it says:
"Output B under options and output settings is used to control the ESC
feature which provides fuel enrichment at part throttle."
It isn't clear to me how changing this setting or the values below
will affect the fuel delivery.
My Output B mode is currently set to Over Pressure. And the Over
Pressure value is -18.12
This is how it was setup with the settings provided to me.
Could you explain any more about this option, or point me to some
documentation on it? I didn't see anything about the Output Settings
in the R4 documentation at all. I would appreciate it very much if
you could tell me what the effect of each setting is for all the
entries under Output settings. I'm guessing some of them do not even
apply to the product I am using?
SplitSec Dude said:The output B setting is only an issue if you have the E suffix version of
the PSC1. If you do, you can set output B for the threshold where you want
enrichment. Output B is usually set to over pressure with an over pressure
limit of 1 psi. In order to get enrichment, you also have to increase the
cell values in the map table at 1 psi. The purpose of the ESC function is
to allow you to add fuel without having the ECU trim it away.
Unless you have a custom unit, the other output settings are not used.
Yes, this is what I meant in the first option I posted about. I disconnected the O2 wires from the AFC, and had the sensor go directly to the ECU as just like stock.ZMN BY U said:DID YOU CUT THE 02 SENSOR WIRE and hook it up stock and try it
peepsalot said:I'd recommend you try option #2 first, no wiring changes required.
If you want a reply from John you might try emailng him directly or calling him. He doesn't seem to get online too often, and sometimes he misses posts like this.
No doubt that John's over-worked and underpaid. I have trouble getting responses to pm's, emails, and voice mails so I'm kinda forced to be uber-patient or figure it out like we are here. Bless his heart for trying though. Some people never get back to their customers AT ALL; at least he get's back at some point.
What map are you running? If we are running diff maps, I'm affraid I'll be adjusting values based off of a different set of original values.
I was running the FMIC map, shoudn't really matter though for the Output B settings. Bascially my theory is that for anything below the Output B setting, the AFC will not alter the signals going to the ECU.tallrd said:No doubt that John's over-worked and underpaid. I have trouble getting responses to pm's, emails, and voice mails so I'm kinda forced to be uber-patient or figure it out like we are here. Bless his heart for trying though. Some people never get back to their customers AT ALL; at least he get's back at some point.
What map are you running? If we are running diff maps, I'm affraid I'll be adjusting values based off of a different set of original values.
John said that the AFC is not altering the signal at all under vacuum, but this turned out to be false. I can post a data log if anyone wants proof. By setting Output B to 0 pressure, I think it will actually make that statement true.
DSMConvert
AWD...say Bye Bye
- :
- Titanium MS6
Wow ok peeps your settings are completely foobarred. I think i've mentioned this in a few other posts but the setting must be set to over pressure and the pressure needs to be listed at -1psi...this is why you're getting a sin wave at idle, b/c the afc is altering signal at anything above -18vac. The msp afc is a custom unit and requires this to run correctly. When we changed the value from 1psi to -18vac on our test setup we instantly got idling issues. However this is a setting on the r4 software so it should only affect people who have uploaded new maps or altered the maps in any way. in the post below i will list the settings again that should be used on the r4 software just to make sure everyone is setting up correctly (if you have never uploaded a new map or altered the current one you do not need to do this unless you want to)
Last edited:
DSMConvert
AWD...say Bye Bye
- :
- Titanium MS6
Ok under the options drop down menu the settings should be selected as follows for each category:
System Settings:
Vacuum/Pressure
Programmable Signal Calibrator
Engine Settings:
4 Cylinders
4 Stroke
Output Settings: *********
Pressure 0 to 30psi
Dont worry about output A
Output B: Over RPM OR Pressure (technically can be just the over pressure selection, but the rpm gives a safety zone incase you develope a severe boost leak)
Over RPM: 6000
Over Pressure: -1
Dont worry about the rest
You must do these in this order, otherwise the values wont be correct, ie -1 at vac/pressure is complete different from -1 at absolute...
System Settings:
Vacuum/Pressure
Programmable Signal Calibrator
Engine Settings:
4 Cylinders
4 Stroke
Output Settings: *********
Pressure 0 to 30psi
Dont worry about output A
Output B: Over RPM OR Pressure (technically can be just the over pressure selection, but the rpm gives a safety zone incase you develope a severe boost leak)
Over RPM: 6000
Over Pressure: -1
Dont worry about the rest
You must do these in this order, otherwise the values wont be correct, ie -1 at vac/pressure is complete different from -1 at absolute...
DSMConvert said:Ok under the options drop down menu the settings should be selected as follows for each category:
System Settings:
Vacuum/Pressure
Programmable Signal Calibrator
Engine Settings:
4 Cylinders
4 Stroke
Output Settings: *********
Pressure 0 to 30psi
Dont worry about output A
Output B: Over RPM OR Pressure (technically can be just the over pressure selection, but the rpm gives a safety zone incase you develope a severe boost leak)
Over RPM: 6000
Over Pressure: -1
Dont worry about the rest
You must do these in this order, otherwise the values wont be correct, ie -1 at vac/pressure is complete different from -1 at absolute...
In that case, the FMIC Map is set wrong, the Over Pressure is -18.12. You should change the download on your website...
New Posts and Comments
- Replies
- 0
- Views
- 64
- Replies
- 2
- Views
- 208
- Replies
- 3K
- Views
- 2M
