well my car was tuned last year with 440's made great power with 306whp at 12psi ona b16, great. but this year i wanted more power and went and stepped up to some precision turbo 680cc injectors with a resistor box.

my tuner puts the resistor box in with the big injectors and builds a new map, this is when things start to get wierd. the car will idle(poorly) and on the dyno the injectors dont know which way to go, there lean one minute rich as hell the next.

why will smaller injectors that dont need a resistor box work perfectly.

but then the big injectors just do what they want.

wiring is good, installation is good, ---


any input in this situation is good as well


ps, wiring, installation, all fuel sytems working perfect and all ignition systems working good.

pss, using aem v.94 1010

car is a 2000 civic si

 

I see you said wiring was perfect, but did he use a mutlimeter to identify which wires go to the injectors?

 

are you ony having problems with idle? if so i suggest using the boost correct table to increase resolution of your fuel map in high vaccum.

if the lean/rich conditions happen at all rpm's make sure that there aren't any trims that are being added or not added at different times. like knock control adding fuel, or air temp adding fuel, etc...

it seems to me that in order to get your temperature corrections right you should zero the tables out and monitor the temps while tuning. after the major tuning is over and it is time to set up the temp corrections use the avg temp that you were tuned at for the zero point of the trim and add or subtract, fuel/timing above and below that point. hth

 

I had the same problem, I switched from 240cc stock injectors to the 680cc injectors and resistor box. If I told the EMS they were 680cc it couls barely start, but run fair above idle. If I told them they were 350cc it would start and idle fine, but bog and go way rich off Idle. After about 2 hours of auto tune and tweaking I got them to run and idle like stock. I can email you my map if your in need, but I'm still NA and none of the boost fuel has been worked on.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by slowsi00 &raquo;</TD></TR><TR><TD CLASS="quote">my tuner puts the resistor box in with the big injectors and builds a new map, this is when things start to get wierd. the car will idle(poorly) and on the dyno the injectors dont know which way to go, there lean one minute rich as hell the next. why will smaller injectors that dont need a resistor box work perfectly. but then the big injectors just do what they want.</TD></TR></TABLE>

This is a common problem with injector swaps. Assuming that all electrical is OK, I would bet that your problem is due to the different injector response characteristics.

Most injectors respond differently than each other. That is, the time it takes from the application of power untill fuel is actually flowing. The ECU gets this response data from the Battery Offset - Primary table (uS vs Batt Volts) or The Battery Offset - Staged tables.

The reason I suggest this is because differences of 300-500uS are typical and if the larger injectors are faster responding (and low impedance ones generally are faster, even with resistor boxes) then this time is flowing fuel thats not accounted for.

If this is the case, it will idle bad but will get better with increasing load. This is because the steady error from the offset table becomes much less significant at higher injector pulsewidths.

We have had people change injectors and then had the car running rich at idle, even though the fuel map was zero!!!!! (offset table error was large enough to support a rich idle!)

Our V1.00 release has alot of the most common injector response curves included with it for your convience. All injectors are driven by an actual AEM EMS and Low Impedance injectors are tested with a resister box for accuracy. If we don't have response curves for your exact injectors and they are somewhat common, we will test them and generate the AEM EMS response data for you for free so we can include it in the next database release. You pay shipping in, we pay UPS ground back to you.

JR

 

woah aem rules


u guys helped me alot out last year....

thanks for the information.

 

slowsi00, are you from chicago?

 

around the area yes....

 

so i can send my injectors to u guys.... and u will send them back to me with the corect voltage reading nessacary.... is there any way u guys can start to build a map for me as well

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by JR From AEM &raquo;</TD></TR><TR><TD CLASS="quote">

This is a common problem with injector swaps. Assuming that all electrical is OK, I would bet that your problem is due to the different injector response characteristics.

Most injectors respond differently than each other. That is, the time it takes from the application of power untill fuel is actually flowing. The ECU gets this response data from the Battery Offset - Primary table (uS vs Batt Volts) or The Battery Offset - Staged tables.

The reason I suggest this is because differences of 300-500uS are typical and if the larger injectors are faster responding (and low impedance ones generally are faster, even with resistor boxes) then this time is flowing fuel thats not accounted for.

If this is the case, it will idle bad but will get better with increasing load. This is because the steady error from the offset table becomes much less significant at higher injector pulsewidths.

We have had people change injectors and then had the car running rich at idle, even though the fuel map was zero!!!!! (offset table error was large enough to support a rich idle!)

Our V1.00 release has alot of the most common injector response curves included with it for your convience. All injectors are driven by an actual AEM EMS and Low Impedance injectors are tested with a resister box for accuracy. If we don't have response curves for your exact injectors and they are somewhat common, we will test them and generate the AEM EMS response data for you for free so we can include it in the next database release. You pay shipping in, we pay UPS ground back to you.

JR</TD></TR></TABLE>

Way to go JR! Do you know if you are going to be including MSD 65lbs settings? I am so PUMPED for 1.00 to come out

 

How about 95# Siemen Deka's? I have them but not installed yet....I can send them out tomorrow.

Oh yeah.....get that 1.0 out to use current users soon!! I cant wait

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by mskibbz-T &raquo;</TD></TR><TR><TD CLASS="quote">Way to go JR! Do you know if you are going to be including MSD 65lbs settings? I am so PUMPED for 1.00 to come out </TD></TR></TABLE>

Currently, we have data for most of the factory Honda, DSM's, and our other plug and play models. We also have generated the data for the full RC Line.

We do not have the Deka or MSD injectors.

If you have 2 good samples, email us at EMSTECH@AEMPOWER with the injector information (brand, P/N, flow etc) and we will verify that we do not have the data already. If so, we will forward you the information on how to send them to us for testing.

Currently, we can only test "top feed" type injectors so hold off on the bottom and side feed types (don't worry, not common on Hondas).

JR

 

I wanna run some MSD injectors some please send them to AEM for testing

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by metal-x &raquo;</TD></TR><TR><TD CLASS="quote">I wanna run some MSD injectors some please send them to AEM for testing </TD></TR></TABLE>

Do you have yours installed yet? I can't afford any downtime since I have a daily driver Lots of people on this board bought the MSDs from Viren so I'm sure someone can send em in

 

i thin kthe supra guys are using hte aem ems with the HKS rail and SD 720cc so if they got that down it should work with the honda i am assuming

 

But why would you have to go through all that. I use the DFI Gen 7 and was running a set of RC 550cc, which were also used on the AEM EMS. I recently swapped out the RC's for a set of Seimen Deka 83lb injectors. After installing them all I had to do was change my injector flow rate from 52lb to 83lb and the car fired up and ran great, just as it did before! Heres my old thread.
https://honda-tech.com/zero...ously