RB25det S14. Injectors resistance bad or ok? - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

OneSicSilvia · 09-12-2012, 06:14 PM

Long story short, motor is on stock boost, finished the swap a few weeks back. Car sputters once in a while while driving. It only seems to do it in the morning (the bad one) a min or so after idling and then driving down my driveway (about 500 ft). I'll turn onto the road, and get about 200ft and the car will loose all power lol. At about 1200 rpms -2k it starts popping and sputtering like its at fuel cut. toss it in neutral, no issues. Back into gear and give it some gas, back to sputtering. Does this for about a min, then seems fine. The other issue is when driving at times, giving it some throttle, it picks up, then seems to break up and loose power, then it picks up again and continues pulling till it start breaking up again. I Ohmed out my injectors today, they all reeled in at about 11.6, 11.7 aside from cylinder 6 which read out at 11.8. Does this seem low? I unplugged my coils when the car was running 1 at a time to see if the motor started sputtering, and it did with all 6 coils so I doubt the coils are bad unless their magically breaking up under any kind of boost. I'm leaning towards the injectors but am not sure really. Let me know your opinions.

Walperstyle · 09-13-2012, 06:14 AM

do you have high or low impedance injectors? Do you have resistors, if yes, what kind?
(I am not familiar with RB25's, but I know if you run low impy injectors you need to have a resistor pack, and I believe (guessing) you want it around 4-5ohms) ...this is turbo KA (and probably other engines too)

Disclaimer, I am still building my powerhouse.

How do your spark plugs look? what is your fuel pressure at?

OneSicSilvia · 09-14-2012, 04:06 AM

I did some poking around on proper impeedance. They are high imp, so 11's seemed good. Spark plugs havnt been pulled yet, and fuel pressure hasnt been checked. I need to get myself an external FPR.

PrimeDirective · 09-14-2012, 08:25 AM

Don't buy a new FPR yet. The stock one should be fine for a stock motor.

You should be checking things like your ignitor chip, coil packs, MAF, and TPS.

09-12-2012, 06:14 PM	#1
OneSicSilvia Leaky Injector Join Date: Aug 2010 Location: Maine Age: 40 Posts: 82 Trader Rating: (1) Feedback Score: 1 reviews	RB25det S14. Injectors resistance bad or ok? Long story short, motor is on stock boost, finished the swap a few weeks back. Car sputters once in a while while driving. It only seems to do it in the morning (the bad one) a min or so after idling and then driving down my driveway (about 500 ft). I'll turn onto the road, and get about 200ft and the car will loose all power lol. At about 1200 rpms -2k it starts popping and sputtering like its at fuel cut. toss it in neutral, no issues. Back into gear and give it some gas, back to sputtering. Does this for about a min, then seems fine. The other issue is when driving at times, giving it some throttle, it picks up, then seems to break up and loose power, then it picks up again and continues pulling till it start breaking up again. I Ohmed out my injectors today, they all reeled in at about 11.6, 11.7 aside from cylinder 6 which read out at 11.8. Does this seem low? I unplugged my coils when the car was running 1 at a time to see if the motor started sputtering, and it did with all 6 coils so I doubt the coils are bad unless their magically breaking up under any kind of boost. I'm leaning towards the injectors but am not sure really. Let me know your opinions.

09-13-2012, 06:14 AM	#2
Walperstyle Nissanaholic! Join Date: Nov 2004 Location: Alberta, Red Derp Age: 44 Posts: 1,729 Trader Rating: (0) Feedback Score: 0 reviews	do you have high or low impedance injectors? Do you have resistors, if yes, what kind? (I am not familiar with RB25's, but I know if you run low impy injectors you need to have a resistor pack, and I believe (guessing) you want it around 4-5ohms) ...this is turbo KA (and probably other engines too) Disclaimer, I am still building my powerhouse. How do your spark plugs look? what is your fuel pressure at? __________________ KA-T ORG-Function over Flush

09-14-2012, 04:06 AM	#3
OneSicSilvia Leaky Injector Join Date: Aug 2010 Location: Maine Age: 40 Posts: 82 Trader Rating: (1) Feedback Score: 1 reviews	I did some poking around on proper impeedance. They are high imp, so 11's seemed good. Spark plugs havnt been pulled yet, and fuel pressure hasnt been checked. I need to get myself an external FPR.

09-14-2012, 08:25 AM	#4
PrimeDirective Zilvia Member Join Date: Jan 2012 Location: Olympia WA Age: 37 Posts: 266 Trader Rating: (3) Feedback Score: 3 reviews	Don't buy a new FPR yet. The stock one should be fine for a stock motor. You should be checking things like your ignitor chip, coil packs, MAF, and TPS.