Sr20det rich at idle then lean with throttle.. please help - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

Cubantunr · 02-08-2013, 05:40 PM

Ok so here's the deal Sr20det redtop s13 hatch. At idle the car runs ok then after about 15 seconds it starts to get very rich and stays that way, I went to give it a little gas and Bam just straight to lean and almost dies. I barely touch the throttle and it jumps from rich to lean, let off gas and back to rich. Stock injectors, nismo fpr. The o rings were bad so I replaced them, set the fpr to 36 idle and 42 with vacuum hose disconnected, the injectors were checked and ultrasonic cleaned all tested good but that doesn't mean they're spraying consistent does it? Checked them with the ohm meter on a cold night and read back 10.7-11 on all 4. Replaced pcv valve and all still the same. The injectors sat with bad gas for about a year before the cleaning. Idk what else it could be. Any help appreciated, thanks.
Btw I'm running walbro 255 fuel pump.

rcdad123 · 02-08-2013, 10:49 PM

MAF sensor, TPS, CTS, check them all

Cubantunr · 02-08-2013, 11:01 PM

Alright I will give them all a look this Sunday n monday, keep u guys informed..

silviaS14guy29 · 02-10-2013, 09:19 PM

Anything with the fuel system is always such a headache! on mine i had a similar issue the ratio was all over the place at certain rpms, it ended up just being a loose ground wire causing the pcm to malfunction. so just keep an eye out for loose grounds, bare wires, etc and print out a wiring diagram it will help in the long run! Best of luck man hope you get her fixed up!

steve shadows · 02-11-2013, 11:40 AM

You pump could be dying also. Walbros do this.

02-08-2013, 05:40 PM	#1
Cubantunr Zilvia Junkie Join Date: Nov 2010 Location: Iowa Posts: 433 Trader Rating: (4) Feedback Score: 4 reviews	Sr20det rich at idle then lean with throttle.. please help Ok so here's the deal Sr20det redtop s13 hatch. At idle the car runs ok then after about 15 seconds it starts to get very rich and stays that way, I went to give it a little gas and Bam just straight to lean and almost dies. I barely touch the throttle and it jumps from rich to lean, let off gas and back to rich. Stock injectors, nismo fpr. The o rings were bad so I replaced them, set the fpr to 36 idle and 42 with vacuum hose disconnected, the injectors were checked and ultrasonic cleaned all tested good but that doesn't mean they're spraying consistent does it? Checked them with the ohm meter on a cold night and read back 10.7-11 on all 4. Replaced pcv valve and all still the same. The injectors sat with bad gas for about a year before the cleaning. Idk what else it could be. Any help appreciated, thanks. Btw I'm running walbro 255 fuel pump.

02-11-2013, 11:40 AM	#5
steve shadows Post Whore! Join Date: Aug 2003 Location: LA and OC Posts: 8,202 Trader Rating: (5) Feedback Score: 5 reviews	You pump could be dying also. Walbros do this. __________________ Like Me on FaceBook !

02-08-2013, 10:49 PM	#2
rcdad123 Zilvia Addict Join Date: Jul 2011 Location: san diego Posts: 639 Trader Rating: (0) Feedback Score: 0 reviews	MAF sensor, TPS, CTS, check them all

02-08-2013, 11:01 PM	#3
Cubantunr Zilvia Junkie Join Date: Nov 2010 Location: Iowa Posts: 433 Trader Rating: (4) Feedback Score: 4 reviews	Alright I will give them all a look this Sunday n monday, keep u guys informed..

02-10-2013, 09:19 PM	#4
silviaS14guy29 Join Date: Feb 2013 Location: philly Posts: 4 Trader Rating: (0) Feedback Score: 0 reviews	Anything with the fuel system is always such a headache! on mine i had a similar issue the ratio was all over the place at certain rpms, it ended up just being a loose ground wire causing the pcm to malfunction. so just keep an eye out for loose grounds, bare wires, etc and print out a wiring diagram it will help in the long run! Best of luck man hope you get her fixed up!