Update on project car - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

DMC · 01-06-2006, 12:42 PM

Last post I made I was having difficulties getting my car to idle correctly and run correctly. Thanks to everyone who helped me, I found out my TPS sensor was not connected tight. I then reset the ecu and she idles fine and runs fine BUT only when the MAF is not connected. So it only runs up to 2500 rpms like every 240 with the maf disconnected. WHen i connect the MAF the car will not idle it stalls, and just doesn't run anywhere near how it should. I replaced the MAF, and the ECU. The problem did not change. I am going to replace the wiring harness as soon as I can get one, but I wanted to see if anyone else had any suggestions.

Its a 1993 ka24de in a 1989 fastback.

jeffg · 01-06-2006, 02:29 PM

MAF ground? Check the resistance between the maf ground and chassis ground. It should be almost nothing. If its higher than a few thousandths (0.00X) I would run a new wire and reground the MAF. Make sure its getting voltage and check for signal on the other wires. Make sure you have signal at the ECU.

Stuff you probably already know, but cant hurt.

J

s14dr1ft3r · 01-06-2006, 02:51 PM

yup. sounds like a ground problem to me too. I've seen poor grounding do some really funny things on various electronics (its what I do for a living).

**ThatGuy** · 01-06-2006, 05:00 PM

I have a suggestion.

POST TECH QUESTIONS IN THE TECH SECTION!

DMCS14 · 01-06-2006, 05:04 PM

ok so you guys are saying that i may not need to replace the wiring harness, just check all the grounds on the harness? Or are you saying that there may be something wrong with the ground to the MAF?

01-06-2006, 12:42 PM	#1
DMC Zilvia Addict Join Date: Jan 2003 Location: Chesapeake, Va Posts: 609 Trader Rating: (0) Feedback Score: 0 reviews	Update on project car Last post I made I was having difficulties getting my car to idle correctly and run correctly. Thanks to everyone who helped me, I found out my TPS sensor was not connected tight. I then reset the ecu and she idles fine and runs fine BUT only when the MAF is not connected. So it only runs up to 2500 rpms like every 240 with the maf disconnected. WHen i connect the MAF the car will not idle it stalls, and just doesn't run anywhere near how it should. I replaced the MAF, and the ECU. The problem did not change. I am going to replace the wiring harness as soon as I can get one, but I wanted to see if anyone else had any suggestions. Its a 1993 ka24de in a 1989 fastback.

01-06-2006, 02:51 PM	#3
s14dr1ft3r Zilvia Member Join Date: Jun 2005 Location: SoCal Age: 45 Posts: 268 Trader Rating: (0) Feedback Score: 0 reviews	yup. sounds like a ground problem to me too. I've seen poor grounding do some really funny things on various electronics (its what I do for a living). __________________ “If everything’s under control, you’re going too slow”. - Mario Andretti

01-06-2006, 05:00 PM	#4
ThatGuy Admin Asshole Join Date: Mar 2002 Location: Retired Age: 45 Posts: 20,394 Trader Rating: (0) Rides Gallery: ThatGuy Feedback Score: 0 reviews	I have a suggestion. POST TECH QUESTIONS IN THE TECH SECTION! __________________ "Speak softly,..." -Pres. Teddy Roosevelt "Be polite, be professional, ..." -Gen. James Mattis

01-06-2006, 05:04 PM	#5
DMCS14 Leaky Injector Join Date: Aug 2002 Location: 1 Posts: 103 Trader Rating: (0) Feedback Score: 0 reviews	ok so you guys are saying that i may not need to replace the wiring harness, just check all the grounds on the harness? Or are you saying that there may be something wrong with the ground to the MAF? Last edited by DMCS14; 01-06-2006 at 08:25 PM..

01-06-2006, 02:29 PM	#2
jeffg Join Date: Dec 2005 Location: Lost in the Mountains Posts: 17 Trader Rating: (0) Feedback Score: 0 reviews	MAF ground? Check the resistance between the maf ground and chassis ground. It should be almost nothing. If its higher than a few thousandths (0.00X) I would run a new wire and reground the MAF. Make sure its getting voltage and check for signal on the other wires. Make sure you have signal at the ECU. Stuff you probably already know, but cant hurt. J