1badteg

I have 880cc precision injectors, they are low impedance (Did they make high impedance?). They are installed on a 99 civic ex with a p28 ecu (Neptune RTP). I have been having issues with misfires quite often and I will notice rich spikes from the misfires and then absence of power obviously. I am trying to figure out if this is because I'm not running a resistor box or is it something entirely different.

I have had this setup for 3 years and I know the ecu will blow if the ohms are to much but I rarely beat on it. So if I install a resistor box will this possibly fix my misfire, or is my ecu possibly dead? (When the ecu is dead the injectors stop functioning completely, right?). I'm just sick and tired of the notorious misfire that has plagued me for the last couple months. This is at idle mostly and hadn't started acting up until I got into a hotter climate. When its WOT it doesn't hesitate either. It's got me stumped.

2kdrift

idk about all atht other stuff. i do know u need to run a resistor box on low impedance. my guess would be you would burn the injector basically immediatly without the box as the voltage will be to high. do it right install the box if you have low impedence, from there you will need to figure out if its faulty ecu, wiring , or the injector. box install is easy just do it

BOOSTINmidori

i'm a complete n00b and having the same problem i've been reading on the computer and i havent saw anything on the resistor boxes. i have a turbo single cam without the box and idk exactly what the need is for?

habib

Runnig low impedance injectors without a resistor box will fry your injector drive in your ecu, the need for the resistor box is because low impedance have different ohm's from saturated injectors.

1badteg

If it will fry the injector drive then wouldn't the injectors not work at all? I have had it this way since early 08 and it starts everytime but misfires. Sounds like a subie at idle.

2kdrift

resister box is used for low impedance injectors. some companies use high impedience like stock honda ones. but things like dsm, injectors are very popular and cheap and they require the box. i got a set of 450cc dsms for about $50 and the resistor box for $20 alot cheaper then $250 high impedance 450 cc's. google dsm install or honda resistor box you will find some how tos


@ 1badteg sould be another issue, if it sounds like a subi it probally means you are running on three cylinders. have u tested spark?

1badteg

I'll check spark wires. I know I'm getting spark from the dizzy to all for wires because I have one of those accel cheapo dizzy caps to view spark. Maybe it's a
bad injector. Anyone know of a place in socal that test injectors?

1badteg

Found out that the low impedance injectors are ran at 10 ohms so they are borderline high/low impedance. The ecu is roughly seeing 1.42 ohms and that why it hasn't melted yet. So should I still swap in a resistor?

boostedcivicsir

yes you should.......it doesnt fry right away. it gets worse with pulse width. when yo beat on it for long periods of time thats when the smoke comes out. and when the smoke comes out, you aint getting it back in.

saturated injectors are 10-12ohm (high)
peak and hold are 2-3ohm (low)

the ecm needs to see the 10-12~ohm resistance, hence the need for a 10w 10ohm resistor.

i am not aware of a borderline but i have seen stranger stuff.

TheStig187

Try this it help me when i was doing it myself
http://www.hondata.com/techinjectorwiring.html

1badteg

youre right, thanks. i had read that the 880cc injectors were 10 ohm but i measured them all at 2.6 ohm. so i am in search of a resistor box. anyone know how to repair injector drives?!? i know its been done just cant find where to buy the parts.

1badteg

another great find. i will be using this for some wiring

BOOSTINmidori

wow that cleared up a lot for me looks like im getting one of those boxes since i just switched to obdI.

latino honda

bump