//Dezod Motorsports// AEM FIC and idle via Paul
09-20-2013, 04:51 PM
#1
//Dezod Motorsports// AEM FIC and idle via Paul
I have had a lot of people talk about not being able to get a good idle on their AEM FIC with their turbo. There are a few things that need to be gone over and done to help this....Allow me to demonstrate and show you HOW to get good idle. It should idle like stock or better even with large injectors or a heat soak.
What's needed to do this?
1) Laptop w/ AEM FIC software installed
2) USB cable
3) OBD2 scan tool that can read fuel trims
Assumptions
AEM FIC is tuned and all parameters are all set incl TPS etc.
You are using the MAF table
Your MAF table is in MAF and Voltage settings
You are using the O2 table
Your O2 MAP is in voltage mode
Proper install with no vac leaks (ZERO)
Stock cams
Your idle is between -20-22 in of hg
Procedure
1) Ensure the turbo system has no vac leaks! This is the biggest shoot yourself in the foot item that leads back to my mantra of have a quality install. Use RTV, pipe sealant, gaskets etc when installing.
2) Fire up that laptop and hook up FIC.
3) Hook up OBD2 scan tool
4) Turn car to ACCII (position before starting)
5) Note MAF voltage minimum voltage (save value)
6) Start car and let fully warm up to about 180*F
7) Make sure your AEM FIC has a zero brake point on the Y axis in the MAF table. In that zero field, enter that min MAF value for the zero row in the MAF table going horizontally across the RPM breakpoints.
***make sure your RPM break points are broken down with some granularity as well. Recall the car revs to 6250, so 6500 as the max value will be just fine and a good minimum RPM point will be 0 RPMS. So your RPM breakpoints should be about every 325RPMS. Note, the first 3 RPM break points will be your idle "pocket".
Note current MAF voltage on OBD2 scan tool
9) See where that falls in your MAF table and make sure it falls on a solid value and isn't between a HUGE interpolation point. In other words, say your MAF voltage at idle is .35, make sure you have a .35 breakpoint on that MAF table or something very close to it.
10) Now go ahead highlight that .35V (or whatever voltage it may be) across entire MAF voltage span horizontally over the RPM breakpoints. Right click on the row and you will see a menu pop up. Hit the "+" once or twice to give a nice buffer on that MAF voltage.
11) Pull up FIC gauges View>Gauges and note MAF in and MAF out. They should be close in proximity.
12) Open up the O2 map and put 0 values in that idle pocket. So say your idle load is about 6 PSIA and you want zeros from 2.5 to 7 PSIA and from say 0-975 or even 0-1300.
13) Now for the fun stuff. Open the Fuel MAP on the FIC and put up LTFT and STFT (Long term fuel trim and Short term fuel trim) on the OBD2 scan tool. Take both STFT and LTFT and add them together. Say you have a LTFT of +10 and a STFT of -20, your total fuel trim would be -10. This means the ECU overall is set to pull out 10% fuel in the overall grand scheme. (adding 10% now, pulling 20% over long term) Figure out your trim value at idle.
***If you have a total sum of say -15. This means 15% fuel will be pulled out. If you have a -30 in the fuel map in your idle pocket, then go ahead and try -33 in that same area and watch the trims adjust. Keep moving it around until you get to a 0 to -5 total total in LTFT + STFT (ideally).
14) Now adjust your fuel map up and down and watch the trims. Your goal should be +/- 10 total. If you can get to +/- 5 or less, even better. Once you get this in check, your idle should be crisp and even better than factory.
Hope this helps the community.
What's needed to do this?
1) Laptop w/ AEM FIC software installed
2) USB cable
3) OBD2 scan tool that can read fuel trims
Assumptions
AEM FIC is tuned and all parameters are all set incl TPS etc.
You are using the MAF table
Your MAF table is in MAF and Voltage settings
You are using the O2 table
Your O2 MAP is in voltage mode
Proper install with no vac leaks (ZERO)
Stock cams
Your idle is between -20-22 in of hg
Procedure
1) Ensure the turbo system has no vac leaks! This is the biggest shoot yourself in the foot item that leads back to my mantra of have a quality install. Use RTV, pipe sealant, gaskets etc when installing.
2) Fire up that laptop and hook up FIC.
3) Hook up OBD2 scan tool
4) Turn car to ACCII (position before starting)
5) Note MAF voltage minimum voltage (save value)
6) Start car and let fully warm up to about 180*F
7) Make sure your AEM FIC has a zero brake point on the Y axis in the MAF table. In that zero field, enter that min MAF value for the zero row in the MAF table going horizontally across the RPM breakpoints.
***make sure your RPM break points are broken down with some granularity as well. Recall the car revs to 6250, so 6500 as the max value will be just fine and a good minimum RPM point will be 0 RPMS. So your RPM breakpoints should be about every 325RPMS. Note, the first 3 RPM break points will be your idle "pocket".
Note current MAF voltage on OBD2 scan tool9) See where that falls in your MAF table and make sure it falls on a solid value and isn't between a HUGE interpolation point. In other words, say your MAF voltage at idle is .35, make sure you have a .35 breakpoint on that MAF table or something very close to it.
10) Now go ahead highlight that .35V (or whatever voltage it may be) across entire MAF voltage span horizontally over the RPM breakpoints. Right click on the row and you will see a menu pop up. Hit the "+" once or twice to give a nice buffer on that MAF voltage.
11) Pull up FIC gauges View>Gauges and note MAF in and MAF out. They should be close in proximity.
12) Open up the O2 map and put 0 values in that idle pocket. So say your idle load is about 6 PSIA and you want zeros from 2.5 to 7 PSIA and from say 0-975 or even 0-1300.
13) Now for the fun stuff. Open the Fuel MAP on the FIC and put up LTFT and STFT (Long term fuel trim and Short term fuel trim) on the OBD2 scan tool. Take both STFT and LTFT and add them together. Say you have a LTFT of +10 and a STFT of -20, your total fuel trim would be -10. This means the ECU overall is set to pull out 10% fuel in the overall grand scheme. (adding 10% now, pulling 20% over long term) Figure out your trim value at idle.
***If you have a total sum of say -15. This means 15% fuel will be pulled out. If you have a -30 in the fuel map in your idle pocket, then go ahead and try -33 in that same area and watch the trims adjust. Keep moving it around until you get to a 0 to -5 total total in LTFT + STFT (ideally).
14) Now adjust your fuel map up and down and watch the trims. Your goal should be +/- 10 total. If you can get to +/- 5 or less, even better. Once you get this in check, your idle should be crisp and even better than factory.
Hope this helps the community.
Last edited by paul_dezod; 09-20-2013 at 05:52 PM.
09-20-2013, 05:45 PM
#4
No doubt! I get countless PMs and emails about this. So I figured this would be an easy one to point people to. I have done this procedure with out kit, custom kits, t-netics kits, descedant kits, PT kits, pull through MAF, blow through MAF etc. Works every time.
09-23-2013, 01:36 PM
#11
Agreed.
10-01-2013, 01:20 PM
#15
10-03-2013, 10:55 PM
#16
Member
SL Member
Join Date: Dec 2009
Posts: 90
FIC
Paul has a very good way of explaining things for the masses. Also, always note that if you did it you own it. I'm sure everyone knows that it is self explanatory that if you botch it don't blame the poster. That all being said, more people need to grow some cajones and get your hands dirty. I am an advocate of google search and DIY when it comes to tuning. Why? Where a crap tune can be dangerous and shorten your engines life a DIY tuner often discovers many new an innovative ideas that are eventually introduced to the rest of the community. I encourage more people to broaden their horizons because that's how wonderful ideas and companies are born.
I will also add one last comment here then I'm off my soap box. If you modify any vehicle remember it is "Modified" how ever little or big you "Modify" a vehicle you must always be prepared to accept the consequences of your actions. In other words stuff will break and it will be expensive especially when you boost anything.
My hats off to the author as always wonderful stuff.
I will also add one last comment here then I'm off my soap box. If you modify any vehicle remember it is "Modified" how ever little or big you "Modify" a vehicle you must always be prepared to accept the consequences of your actions. In other words stuff will break and it will be expensive especially when you boost anything.
My hats off to the author as always wonderful stuff.
10-04-2013, 01:39 PM
#17
Paul has a very good way of explaining things for the masses. Also, always note that if you did it you own it. I'm sure everyone knows that it is self explanatory that if you botch it don't blame the poster. That all being said, more people need to grow some cajones and get your hands dirty. I am an advocate of google search and DIY when it comes to tuning. Why? Where a crap tune can be dangerous and shorten your engines life a DIY tuner often discovers many new an innovative ideas that are eventually introduced to the rest of the community. I encourage more people to broaden their horizons because that's how wonderful ideas and companies are born.
I will also add one last comment here then I'm off my soap box. If you modify any vehicle remember it is "Modified" how ever little or big you "Modify" a vehicle you must always be prepared to accept the consequences of your actions. In other words stuff will break and it will be expensive especially when you boost anything.
My hats off to the author as always wonderful stuff.
I will also add one last comment here then I'm off my soap box. If you modify any vehicle remember it is "Modified" how ever little or big you "Modify" a vehicle you must always be prepared to accept the consequences of your actions. In other words stuff will break and it will be expensive especially when you boost anything.
My hats off to the author as always wonderful stuff.
Hi Dan! Thanks for the kind and truthful words.
10-15-2013, 01:45 PM
#18
may i add to this,that you should have colder spark plugs with the proper gap when boost,cause from my experience that affects the idle also...if you dont have colder plugs and running stock gap,it will cause bad idle....even if you have a good tune...
10-15-2013, 01:46 PM
#19
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Music City Scions
SL Member
Join Date: Mar 2009
Location: Nashville, TN
Posts: 1,372
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01-14-2014, 02:50 PM
#20
I have run stock plugs, colder plugs with stock gap and colder plugs with tighter gaps on the AEM FIC and all of which can be tuned fine. HOWEVER, let me state that you can not tune out mechanical problems. So if you have an injector not firing right, a SUPER large injector at low pulse width, a small inconsistent vacuum leak etc....All of which will rear their heads.
