Biggest faults in AEM EMS?
#1
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Biggest faults in AEM EMS?
Hey, joining the AEM crew shortly... just wondered what the MIATA guys have been having issues with that have went unspoken on here.
feedback on the setup besides the first impressions i have read here would be great.
im on the AEM forums too i just want to compare what i read there to what you guys are having issues with.
thanks
-Matt
feedback on the setup besides the first impressions i have read here would be great.
im on the AEM forums too i just want to compare what i read there to what you guys are having issues with.
thanks
-Matt
#5
1) Very random misfire out of nowhere, like every 15 mins. Slightly annoying when it happens. Cause unknown. I've seen this in 3 ECUs and 2 cars, inluding a miata ECU and a Honda ECU.
2) No 'D' term (the D in PID) in the boost controller. Therfore difficult to tune out overshoot when running closed loop boost.
3) No 'D' term in VVT.
4) No raised idle speed *target* for when a/c is on. (It does have a rough idle up function which simply adds duty cycle to the IAC.
5) Can't have 2 separate temperature setpoints for the 2 fans
Of the above the lack of 'D' in boost control is the most irritating.
The misfire is the only one with no workaround.
Other than that it is very good. It does a lot of things few other ECUs do, and some which not all ECUs have. Just off the top of my head:
1) fast datalogging of ANY variables, internal ones included
2) individual cylinder spark and injection trim
3) enrichment on high EGTs
4) copy tables to/from Excel
5) inj duty cycles can be multiplied by MAP so that it looks flat vs. MAP - this makes tuning/reviewing fuel much easier
6) can use MAF input
2) No 'D' term (the D in PID) in the boost controller. Therfore difficult to tune out overshoot when running closed loop boost.
3) No 'D' term in VVT.
4) No raised idle speed *target* for when a/c is on. (It does have a rough idle up function which simply adds duty cycle to the IAC.
5) Can't have 2 separate temperature setpoints for the 2 fans
Of the above the lack of 'D' in boost control is the most irritating.
The misfire is the only one with no workaround.
Other than that it is very good. It does a lot of things few other ECUs do, and some which not all ECUs have. Just off the top of my head:
1) fast datalogging of ANY variables, internal ones included
2) individual cylinder spark and injection trim
3) enrichment on high EGTs
4) copy tables to/from Excel
5) inj duty cycles can be multiplied by MAP so that it looks flat vs. MAP - this makes tuning/reviewing fuel much easier
6) can use MAF input
#7
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2) No 'D' term (the D in PID) in the boost controller. Therfore difficult to tune out overshoot when running closed loop boost.
3) No 'D' term in VVT.
4) No raised idle speed *target* for when a/c is on. (It does have a rough idle up function which simply adds duty cycle to the IAC.
5) Can't have 2 separate temperature setpoints for the 2 fans
Of the above the lack of 'D' in boost control is the most irritating.
The misfire is the only one with no workaround.
Other than that it is very good. It does a lot of things few other ECUs do, and some which not all ECUs have. Just off the top of my head:
1) fast datalogging of ANY variables, internal ones included
2) individual cylinder spark and injection trim
3) enrichment on high EGTs
4) copy tables to/from Excel
5) inj duty cycles can be multiplied by MAP so that it looks flat vs. MAP - this makes tuning/reviewing fuel much easier
6) can use MAF input
3) No 'D' term in VVT.
4) No raised idle speed *target* for when a/c is on. (It does have a rough idle up function which simply adds duty cycle to the IAC.
5) Can't have 2 separate temperature setpoints for the 2 fans
Of the above the lack of 'D' in boost control is the most irritating.
The misfire is the only one with no workaround.
Other than that it is very good. It does a lot of things few other ECUs do, and some which not all ECUs have. Just off the top of my head:
1) fast datalogging of ANY variables, internal ones included
2) individual cylinder spark and injection trim
3) enrichment on high EGTs
4) copy tables to/from Excel
5) inj duty cycles can be multiplied by MAP so that it looks flat vs. MAP - this makes tuning/reviewing fuel much easier
6) can use MAF input
EDIT: I like the fact that you can configure the check engine light as an indicator of basically anything, as wired. I've used to indicate when it senses knock, when my antilag is on, right now it's used to show when the radiator fans turn on, to see if my setpoints were correct with the coolant reroute. It's good to know if your fans are running when they shouldn't be.
And I like my Serial Gauge, which can be configured to display a bunch of different parameters in a 2" gauge.
#8
#5 is aka "boost comp" method. The Electromotive TEC was the first to do this, and they called it "linear thermodynamics" or some such.
If you set it up as a straight, then your fuel map looks flat. Instead of actual on times, it roughly displays voumetric efficiency, which doesn't change much with MAP.
e.g. at 4000 rpm, instead of
25 kPa - 1mS
50 kPa - 2mS
100 kPa - 4mS
150 kPa - 6mS
you get
25 kPa - 4mS
50 kPa - 4mS
100 kPa - 4mS
150 kPa - 4mS
.. adn the AEM automatically multiplies the numbers by MAP/100.
Makes viewing understanding and editing the fuel table much easier.
If you set it up as a straight, then your fuel map looks flat. Instead of actual on times, it roughly displays voumetric efficiency, which doesn't change much with MAP.
e.g. at 4000 rpm, instead of
25 kPa - 1mS
50 kPa - 2mS
100 kPa - 4mS
150 kPa - 6mS
you get
25 kPa - 4mS
50 kPa - 4mS
100 kPa - 4mS
150 kPa - 4mS
.. adn the AEM automatically multiplies the numbers by MAP/100.
Makes viewing understanding and editing the fuel table much easier.
#9
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Oh ok, I know what you mean then. From what I recollect from the AEM class I went to, there is a 2-D fuel trim table (map & fuel trim) that you use for this. You set your fuel map to all the same values per rpm, and the trim table adds fuel per MAP. I forget what the value was, but on all their cars and all sorts of setups they found a value of xxx more fuel per PSI worked pretty close.
Or I could be way off on this, it's been many years.
I would find that more confusing, as the fuel map is flat like you said. I like seeing the fuel map in graph form, where a higher peak is more fuel.
Or I could be way off on this, it's been many years.
Makes viewing understanding and editing the fuel table much easier.
#11
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That's what I figured, as my fuel map isn't a constant slope per RPM column. I think Mitch actually said they use closed loop WBO2 fueling to trim the fuel beyond what the boost comp table. I never was able to figure out how to get it to O2 trim quick enough w/o overshooting, etc so I only tried it for an hour and decide it wasn't worth the hassle setting up. I actually run open loop everywhere but idle, that's how lazy I am. To each his own.
#12
I love my EMS. It took a while to figure out, simply because there are a million options, but it is super powerful. Only complaint I have is on earlier motors it takes more cranks to get it started (EMS waits for more revolutions to see a crank signal).
Also for the vehicle hick-up. My engine will just randomly drop in RPM for a split second and come up back, but only when cruising in 4th or 5th. I figured it was a problem with my old ECU, but problem exists now with two stock 1.6 ecu's, two motors, and on the AEM EMS. I tried fixing it with cops, but that didn't work either. I've just given up and accept it.
Also for the vehicle hick-up. My engine will just randomly drop in RPM for a split second and come up back, but only when cruising in 4th or 5th. I figured it was a problem with my old ECU, but problem exists now with two stock 1.6 ecu's, two motors, and on the AEM EMS. I tried fixing it with cops, but that didn't work either. I've just given up and accept it.
#14
This is actually really good info. You guys with EMSs should voice these wants/needs to the forum on AEM's website.
AEM's engineer peeps have been taking user feedback pretty seriously for the Series 2 development, and then working them into future releases of the software. Okay, this doesn't necessarily help the Series 1 guys but would be a big big plus for Series 2 users.
AEM's engineer peeps have been taking user feedback pretty seriously for the Series 2 development, and then working them into future releases of the software. Okay, this doesn't necessarily help the Series 1 guys but would be a big big plus for Series 2 users.
#15
For posterity, which I posted in another thread
The AEM EGT inputs are NOT compatible with standard thermocouples. If you want to use standard thermocouples, you will need an interface box (I explained this in a thread which minime started). You will also need to modify the AEM circuit board. BTDT.
The AEM knock sensor input is NOT compatible with the 99+ factory knock sensor. It is compatible with GM "tuned" knock sensors (e.g. Saturn), but those knock sensors are NOT tuned to a frequency which the miata motor knocks at. To connect the 99+ factory sensor to the AEM, I posted an interface circuit, which is tuned to the 13 kHz which my motor knocks at, in the ECU section. (built motors may knock at a slightly different frequency)
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The AEM EGT inputs are NOT compatible with standard thermocouples. If you want to use standard thermocouples, you will need an interface box (I explained this in a thread which minime started). You will also need to modify the AEM circuit board. BTDT.
The AEM knock sensor input is NOT compatible with the 99+ factory knock sensor. It is compatible with GM "tuned" knock sensors (e.g. Saturn), but those knock sensors are NOT tuned to a frequency which the miata motor knocks at. To connect the 99+ factory sensor to the AEM, I posted an interface circuit, which is tuned to the 13 kHz which my motor knocks at, in the ECU section. (built motors may knock at a slightly different frequency)
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#19
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Thanks for the info guys!
I decided to go through with getting the EMS from Emilio @ 949racing finally.
Slightly off topic, but would anyone be willing to send their tune to me to look over for a 1.6 setup to compare to the base maps that AEM should include?
My actual setup will be 2860RS 0.86 with RC 440's and GM 3 Bar map/IAT.
Another question is widebands. What widebands are people using, what are the most accurate and what hooks up easiest to the EMS? Im on dialup at the parents house over the break, or i would research a little more.
I decided to go through with getting the EMS from Emilio @ 949racing finally.
Slightly off topic, but would anyone be willing to send their tune to me to look over for a 1.6 setup to compare to the base maps that AEM should include?
My actual setup will be 2860RS 0.86 with RC 440's and GM 3 Bar map/IAT.
Another question is widebands. What widebands are people using, what are the most accurate and what hooks up easiest to the EMS? Im on dialup at the parents house over the break, or i would research a little more.