Spark knock.... wtf - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

240silvia · 06-26-2008, 07:59 PM

93 ka24de NA w/ 4100 miles

So I have some spark knock aka, detonation going on in my motor. This is what I have done...

New fuel filter
New plugs
sprayed carb cleaner all over the intake mani to check for vac leaks, the idle didn't change, so it's not that
fuel pressure regulator has plenty of vac
secondary butterflies has plenty of vac
93 in the gas tank
I put seafoam through the fuel tank and also through a vac source.

the car runs PERFECT at idle. When I go to take off, up to about 30% throttle I have a lot of spark knock. Over 30% throttle, it pretty much goes away. WEIRD!!!!!!!!! I went for a drive down the street, pulled the first plug, and it was WHITE!!!! It's running lean as hell!

I have a few friends that thing it's a fuel pump going out. Any suggestions?

silpena · 06-26-2008, 08:20 PM

have you tried looking at your timing???? i would have looked at there first ontop of everything u listed.

ATLspeed · 06-26-2008, 08:27 PM

+1 timing on the timing

240silvia · 06-26-2008, 08:30 PM

well you guys nailed the one thing i didn't list, lol. I have checked and re checked it. It's a lil retarded to try and compensate for the knock.

240silvia · 06-30-2008, 12:54 AM

I double checked the timing. It's still good. Any ideas?

Def · 06-30-2008, 01:03 AM

Are all plugs white, or just number 1?

Could be a dead/clogged injector. Next step would be to check fuel pressure.

DDSR240 · 06-30-2008, 01:09 AM

Check the heat range on you plugs..and if posible see who you got the car from and see if they ever got the head searviced maby it was machined down(very common) if it blew a hg.

240silvia · 06-30-2008, 07:08 PM

all plugs are white. And the stock motor isn't in the car. I pulled this motor out in february. It was running fine. I don't know wtf is going on. And the fuel pressure is fine. This just doesn't make any sense.

Possible engine harness being bad?????

I checked the codes on the ECU. With the ignition OFF I got 11, 12, 14, 21.

Which is...

11 - Camshaft position sensor

12 - Mass Air Flow Meter Sensor

14 - Vehicle Speed Sensor signal circuit is open (speedo isn't working while driving)

21 - Ignition signal in the primary circuit is not being entered to the ECU during cranking or tuning

With th eignition ON I got a 55, which is no problems. That is weird to me.

Any ideas?

06-26-2008, 07:59 PM	#1
240silvia Nissanaholic! Join Date: Jul 2002 Location: Wilmington NC Age: 40 Posts: 2,060 Trader Rating: (3) Feedback Score: 3 reviews	Spark knock.... wtf 93 ka24de NA w/ 4100 miles So I have some spark knock aka, detonation going on in my motor. This is what I have done... New fuel filter New plugs sprayed carb cleaner all over the intake mani to check for vac leaks, the idle didn't change, so it's not that fuel pressure regulator has plenty of vac secondary butterflies has plenty of vac 93 in the gas tank I put seafoam through the fuel tank and also through a vac source. the car runs PERFECT at idle. When I go to take off, up to about 30% throttle I have a lot of spark knock. Over 30% throttle, it pretty much goes away. WEIRD!!!!!!!!! I went for a drive down the street, pulled the first plug, and it was WHITE!!!! It's running lean as hell! I have a few friends that thing it's a fuel pump going out. Any suggestions?

06-26-2008, 08:27 PM	#3
ATLspeed Zilvia Addict Join Date: Jan 2007 Location: Eden, MD, USA Age: 38 Posts: 921 Trader Rating: (14) Rides Gallery: ATLspeed Feedback Score: 14 reviews	+1 timing on the timing __________________ 93 s13 Vert - 2jz/cd009 -- parted/sold 95 Supra Turbo

06-30-2008, 01:09 AM	#7
DDSR240 Zilvia Member Join Date: Dec 2006 Location: South Carolina Age: 38 Posts: 259 Trader Rating: (0) Feedback Score: 0 reviews	Check the heat range on you plugs..and if posible see who you got the car from and see if they ever got the head searviced maby it was machined down(very common) if it blew a hg. __________________

06-26-2008, 08:20 PM	#2
silpena Zilvia Addict Join Date: Jan 2008 Location: LIVE OAK,CA Age: 38 Posts: 834 Trader Rating: (2) Feedback Score: 2 reviews	have you tried looking at your timing???? i would have looked at there first ontop of everything u listed.

06-26-2008, 08:30 PM	#4
240silvia Nissanaholic! Join Date: Jul 2002 Location: Wilmington NC Age: 40 Posts: 2,060 Trader Rating: (3) Feedback Score: 3 reviews	well you guys nailed the one thing i didn't list, lol. I have checked and re checked it. It's a lil retarded to try and compensate for the knock.

06-30-2008, 12:54 AM	#5
240silvia Nissanaholic! Join Date: Jul 2002 Location: Wilmington NC Age: 40 Posts: 2,060 Trader Rating: (3) Feedback Score: 3 reviews	I double checked the timing. It's still good. Any ideas?

06-30-2008, 01:03 AM	#6
Def Post Whore! Join Date: Apr 2004 Location: Houston, TX Posts: 2,701 Trader Rating: (16) Feedback Score: 16 reviews	Are all plugs white, or just number 1? Could be a dead/clogged injector. Next step would be to check fuel pressure.

06-30-2008, 07:08 PM	#8
240silvia Nissanaholic! Join Date: Jul 2002 Location: Wilmington NC Age: 40 Posts: 2,060 Trader Rating: (3) Feedback Score: 3 reviews	all plugs are white. And the stock motor isn't in the car. I pulled this motor out in february. It was running fine. I don't know wtf is going on. And the fuel pressure is fine. This just doesn't make any sense. Possible engine harness being bad????? I checked the codes on the ECU. With the ignition OFF I got 11, 12, 14, 21. Which is... 11 - Camshaft position sensor 12 - Mass Air Flow Meter Sensor 14 - Vehicle Speed Sensor signal circuit is open (speedo isn't working while driving) 21 - Ignition signal in the primary circuit is not being entered to the ECU during cranking or tuning With th eignition ON I got a 55, which is no problems. That is weird to me. Any ideas?