RANDOM ASS JERKING. ughh - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

Anto · 01-15-2008, 04:58 AM

It's been happening for a while now.
I get random jerks while driving on the freeway. Usually it's when I hit a small bump in the road - car starts jerking 4 or 5 times, then goes back to normal.

By "jerking", I mean the car feels like it loses power for a bit then gets back on, like the spark is being cut.
If I put it in neutral going over a bump, the RPMs dip & causes the car to stall out as well.

First thing I checked? Knock sensor. I replaced it with a different one, then I hardwired a resistor to the ECU wire. I get nothing.
Cleaned out my IAA with intake cleaner. Doesn't really help.
Checked for loose ground wires. They're all good.

For some reason my car like to misfire at idle as well, but it only does it half of the time. The car shakes back and forth and puffs out the exhaust like it was a cammed big block.

WTF is going on?

hellaflush · 01-15-2008, 05:02 AM

checked your O2 sensor?

Koopa Troopa · 01-15-2008, 05:09 AM

KA24 or SR? I'm guessing hitting the bumps is causing a wire with a loose connection to move....

TOMKAIRA93 · 01-15-2008, 05:51 AM

Quote:

Originally Posted by Koopa Troopa

KA24 or SR? I'm guessing hitting the bumps is causing a wire with a loose connection to move....

I second that koopa.

*brndck* · 01-15-2008, 08:34 AM

"ass jerking"? sorry i just thought it sounded funny.
check your battery terminals. make sure they're clean and tight.
(no i'm not trying to be rude or anything, but i see ALOT of electrical problems at work that are nothing more than shitty terminals that are all corroded and eaten away)

*MELLO*SOS* · 01-15-2008, 09:13 AM

yeah you have a short or loose connection somewhere.

Pull codes from the ECU
check the ECU harness connector make sure its bolted tightly to the ECU
check wire loom above front left tire to make sure it's not shredded
check your MAF connector
check your CAS connector
check your plug wires & coil wiring if it's a KA.

gl... only so much we can suggest youre gonna have to find the short yourself. Let the engine idle and touch/move every connection you can see until the motor bogs.

01-15-2008, 04:58 AM	#1
Anto Zilvia Addict Join Date: Jan 2006 Location: California Posts: 862 Trader Rating: (2) Feedback Score: 2 reviews	RANDOM ASS JERKING. ughh It's been happening for a while now. I get random jerks while driving on the freeway. Usually it's when I hit a small bump in the road - car starts jerking 4 or 5 times, then goes back to normal. By "jerking", I mean the car feels like it loses power for a bit then gets back on, like the spark is being cut. If I put it in neutral going over a bump, the RPMs dip & causes the car to stall out as well. First thing I checked? Knock sensor. I replaced it with a different one, then I hardwired a resistor to the ECU wire. I get nothing. Cleaned out my IAA with intake cleaner. Doesn't really help. Checked for loose ground wires. They're all good. For some reason my car like to misfire at idle as well, but it only does it half of the time. The car shakes back and forth and puffs out the exhaust like it was a cammed big block. WTF is going on?

01-15-2008, 05:09 AM	#3
Koopa Troopa Post Whore! Join Date: Sep 2006 Location: 北谷著, 沖縄県、日本 Posts: 2,565 Trader Rating: (3) Feedback Score: 3 reviews	KA24 or SR? I'm guessing hitting the bumps is causing a wire with a loose connection to move.... __________________ Buy my Stillway shifter!

01-15-2008, 05:02 AM	#2
hellaflush Zilvia Member Join Date: Dec 2007 Location: australia Age: 38 Posts: 281 Trader Rating: (0) Feedback Score: 0 reviews	checked your O2 sensor?

01-15-2008, 08:34 AM	#5
brndck Premium Member Join Date: Jun 2003 Location: torrance, ca Age: 43 Posts: 12,686 Trader Rating: (130) Rides Gallery: brndck Feedback Score: 130 reviews	"ass jerking"? sorry i just thought it sounded funny. check your battery terminals. make sure they're clean and tight. (no i'm not trying to be rude or anything, but i see ALOT of electrical problems at work that are nothing more than shitty terminals that are all corroded and eaten away)

01-15-2008, 09:13 AM	#6
MELLOSOS* LAID OUT Join Date: Mar 2004 Location: LAS VEGAS Age: 43 Posts: 2,015 Trader Rating: (1) Rides Gallery: MELLO*SOS Feedback Score: 1 reviews	yeah you have a short or loose connection somewhere. Pull codes from the ECU check the ECU harness connector make sure its bolted tightly to the ECU check wire loom above front left tire to make sure it's not shredded check your MAF connector check your CAS connector check your plug wires & coil wiring if it's a KA. gl... only so much we can suggest youre gonna have to find the short yourself. Let the engine idle and touch/move every connection you can see until the motor bogs.