Someone please help... - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

lextechga · 07-28-2007, 03:20 PM

my sr has a very bad misfire starting at 3000rpms. the car jerks violently and will not accelerate normally under any throttle position. i have tried replacing my mafs with one from a ka24e with the same results and my plug is also not corroded. i can't find any boost leaks, and i have brand new ngk 3330 plugs gapped to .030. the car also will die if you give it gas when you first start it up, it also doesn't seem to find a steady idle. don't ask why but i tried tapping on the side of the ecu and the idle will change and sometimes also die. anyone with any advice???

2plus4plus0eq6 · 07-28-2007, 03:42 PM

im thinking its a loose connection if your idle changes when you tap the ecu. Try taking it apart

lextechga · 07-28-2007, 04:17 PM

to be honest its more of a bang than a tap(starting to get pissed with the car), but it still shouldn't do this. i've made sure the 10mm was tight and playing around with the wires doesn't cause a change. and a little more back ground info. the car started out with a slight miss(compared to the miss now, sounded like a wrx under load), so i removed the mafs and cleaned it, didn't really help. then i unplugged the mafs and started the car and gave it gas to keep it running, (i realize i should have had the car running and then unplugged it) that's when the misfire got really bad and made the car start to jerk at about 2500-3000rpms.

cotbu · 07-28-2007, 04:30 PM

Any smoke with that jerk? Boostleak possibly, since your sure it's not the MAFS.

07-28-2007, 03:20 PM	#1
lextechga Join Date: Jul 2007 Location: Atlanta Age: 42 Posts: 3 Trader Rating: (0) Feedback Score: 0 reviews	Someone please help... my sr has a very bad misfire starting at 3000rpms. the car jerks violently and will not accelerate normally under any throttle position. i have tried replacing my mafs with one from a ka24e with the same results and my plug is also not corroded. i can't find any boost leaks, and i have brand new ngk 3330 plugs gapped to .030. the car also will die if you give it gas when you first start it up, it also doesn't seem to find a steady idle. don't ask why but i tried tapping on the side of the ecu and the idle will change and sometimes also die. anyone with any advice???

07-28-2007, 03:42 PM	#2
2plus4plus0eq6 Zilvia Junkie Join Date: Oct 2005 Location: Canada, BC Posts: 390 Trader Rating: (0) Feedback Score: 0 reviews	im thinking its a loose connection if your idle changes when you tap the ecu. Try taking it apart __________________

07-28-2007, 04:30 PM	#4
cotbu Post Whore! Join Date: Sep 2005 Location: SWFL Age: 50 Posts: 3,318 Trader Rating: (3) Feedback Score: 3 reviews	Any smoke with that jerk? Boostleak possibly, since your sure it's not the MAFS. __________________ LoverTechnologies "Half Broken Things!"

07-28-2007, 04:17 PM	#3
lextechga Join Date: Jul 2007 Location: Atlanta Age: 42 Posts: 3 Trader Rating: (0) Feedback Score: 0 reviews	to be honest its more of a bang than a tap(starting to get pissed with the car), but it still shouldn't do this. i've made sure the 10mm was tight and playing around with the wires doesn't cause a change. and a little more back ground info. the car started out with a slight miss(compared to the miss now, sounded like a wrx under load), so i removed the mafs and cleaned it, didn't really help. then i unplugged the mafs and started the car and gave it gas to keep it running, (i realize i should have had the car running and then unplugged it) that's when the misfire got really bad and made the car start to jerk at about 2500-3000rpms.