please tell me how to wire in my injector resistor pack. i bought a harness for high impedance with n333 ecu and my car is an early 87 with low impedance and n332 ecu. i have the old harness with the plug and the resistor pack already. just need to know where to run the wires. thanks in advance for anyone that helps

p.s. can i run the n332 ecu when the resistor pack is installed?

 

add a 10A 10ohm resistor inline for each injector wire, easier than ******* with the resistor pack.

 

I cant seem to find a resistor with amp specs. Only watts and ohm. Any idea how many watts?

 

here is a simple solution even though irrelevant.

"Since watts are amps multiplied by volts, there is a simple relationship between them."

a 10watt resistor would flow 120amps @ 12 volts.

 

Watts is volts * amps on dc. 120 amps * 12 volts is a touch more than 10 watts. 1440 watts i believe.

 

ohms law... http://en.wikipedia.org/wiki/Ohm%27s_law

 

ok... i got the resistors from radio shack and installed them. now the car idles high around 1k and my afr is around 11.2/11.3... so i take it for a drive and it wants to go more lean the more revs it builds. until 3k when the secondaries kick in. then it spikes back over into the 12.2/12.5 range.

to make a long story short. the p.o. hacked my harness bad with crimp connectors. so i decided to replace it. the one i bought needed the injector plugs switched to my low imp. injectors.

i feel kinda dumb for asking this. but would my car run at all if the primary injector plugs were wired backwards?

again... any imput is appreciated

 

Well I determined I had the plugs for the primaries wired backwards. Switched them around and took it for a drive. Ran great at first. The closer it got to full temp the more it wanted to go lean when cruising. Once it reaches temp it goes all the way lean and will barely run. Let it cool down and the process repeats itself. Wtf is going on here?

My motor only has a few thousand miles on it and I dont wanna burn it up.

Anyone have any ideas? I could really use some help about now.

 

I was thinking that the injector wires' orientation was irrelevant... or so I seem to remember reading somewhere on this site.

 

read the thread. i had to install resistors. so if they were wired backwards the resistors would be on the - wire instead of the + and not doing anything. so yes... in this case it matters.

 

sure they are low impedence injectors?

 

yeah. before the harness swap i was running the resistor box. hooked up.

 

Stk resistors in the solenoid resistor package were/ are 6ohms.

Frankly I don't see how it makes much difference which wire on the injector gets the resistor. The resistor is there to limit the current going thru the injector driver inside the ECU. If memory serves.

 

is there anything that would make the engine get no fuel when it reaches temp?

 

You might want to test the Water Thermosensor and the IAT in the AFM. And check for codes too.

 

made the tester and checked for codes. no codes
now the car is really hard to start like its getting no fuel.
i have plenty of pressure at the gauge on the regulator.
tried changing the maf. same thing
tried a different ecu as well. figured might as well since i have it laying around. same thing .
working on getting the thermosensor out...


got it looking decent. now if i can get the damn thing to run right.

 

So what exactly is the purpose of this whole endeavor? You had a low imp turbo ecu you then swicth to a high imp turbo ecu so you can run low imp injectors....wtf?. Unless of course I'm missing something...

 

the original harness was hacked up by the previous owner.
lots of butt connectors and whatnot.
it had wiring issues because of it and so i decided it would be easier to replace than fix.

 

Somewhat on the line of what Satch mentioned.............when the engine water is cold, the ECU supplies more fuel (richer) until the engine water temp gets up to the ??? around 120*F figure, then it gets a leaner mixture.

If a water thermosensor was disconnected the ECU would default to 178*F .......meaning you'd be seening no diff b/t hot and cold engine temps. So I assume that sensor is indeed connected up good.

I kinda think your water thermosensor is working though 'cause it seems that is what is happening with your car. Cold.....fine............hot.....lean.

N332...N333 swapping 'em out b/t each other should cause no fuel problem whatsoever. The injectors were low impedence (low resistance) on early cars so a six ohm resistor was put inline with 'em to prevent damage to the injector drivers inside the ECU. Plain as that. Been there, done that swap thing myself. No difference.

I'd buy a RTEK2.0 and enrichen the mixture if that's your problem.

OR monitor the fuel pressure as you drive the car and see if that is the problem. The pressure should rise as you depress the throttle and drop when you let off. And it should rise one pound per square inch as you get into boost. Idle pressure should be 28-33 psi. And if your idling the car and pinch off the vacuum hose to the fuel pressure regulator the pressure should rise from 28psi approx to around 39psi. The 39psi simulating atmospheric pressure with no boost or vacuum involved.

Just buy a fuel pressure gauge and tee it to the fuel feed line b/t the fuel filter and engine and montior the gauge while driving. Buy some long fuel line and tie the gauge to the windhield wiper or such. Been there done that. Buy a cheap fire extinguisher just in case you foul up.

You say you've no codes so that Should mean the temp sensors are connected, both water and air temp.

Just EXACTLY where do you have the vacuum line for the FPR going to??????? What nipple??? Got a picture of that?????? The nipple that is. Same with the air pressure/boost pressure sensor. Is it for SURE going to a source that is vaccuum and not just a fresh air nipple?

 

the vacuum line for the FPR is hooked to the motor side of the lower intake mani.
the boost sensor is connected to the upper intake mani. teed with the BOV.

 

thermosensor tested good.
quick question. when i start the car (keep in mind its barely running very rough at this point) and i hop out and look at the fuel pressure gauge the needle is hopping around between 23ish to 35ish. shut it off and the pressure drops rapidly to zero. shouldn't the pressure remain a lil longer than that?

 

sounds like you have an issue in the tank. the pump hose is bypassing and pushing fuel back into the tank versus the rail or the pump is on it's way out. the fuel filter being clogged up can also cause similar issues.

lastly a stuck open injector will also cause erratic pressure readings but is the least common of the listed possibilities.

 

thanks karack i will do some more digging.
tested the voltage at the fuel pump and its really low and pulsing between 2-5 volts.
time for a pump rewire?

 

yes, or trace out where the voltage is bleeding off from. not too difficult to check the voltage in/out from the black/yellow relay under the dash just to the right of the steering column.

 

The pressure should stay at approz 35psi after the engine is shut off. And should stay up above say 20psi after 30 minutes. There's exact figures in the FSM.

What holds the pressure is .........the pressure is caught b/t a checkvalve in the fuel pump itself and and the FPR (I'm talking stk fpr, not aftermarket stuff). So a failed checkvalve in the fuel pump could cause the quick loss of pressure after the fuel pump is shut off.

Some things you say don't mesh. IF your in boost and your afr's are in the ??? 11-13 range I fail to see how a pump that is getting only the voltage you mention could keep it up in the 11-13 range much less explain how you have lean afr before boosting. That does not mesh in my opinion.

IF a turbo car then low voltage could be caused by bad contacts in the fuel pump relay/resistor package and you could just bypass the relay in that package to prove it. But I really dont see how you get rich aft in boost and lean in normal