running better with maf unplugged? - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

aurora · 11-25-2008, 01:21 PM

My sohc 240 hasnt been undrivable for over a month now, and ive been trying to figure out wats wrong, but i cant figure it out.

With the MAF plugged in, my car starts just fine. The car doesnt idle since the revs drop down soon after the car starts. If i press down the throttle too fast, the car instantly dies. If i ease the throttle, i can keep the revs up high enough that the car doesnt die. However, once i hit 2000rpm, the car instantly dies.

With the MAF unplugged, the car idles just fine. I can rev the engine fine as well. However, it bogs alittle after 2000rpm. Ive also succeeded in driving short distances

Ive replaced the coolant temp sensor, ignition coil, sparkplugs, distributor rotor and cap, injectors, injector connectors.

Im guessing i need to replace the MAF, but after searching, it seems like thats its never really the problem.

Can you guys help me out?

s13 @ fullboost · 11-25-2008, 01:42 PM

You know I am having similar problems right now so I would really like to see some good answers and maybe we can both fix our cars

!Zar! · 11-25-2008, 01:49 PM

Sounds like you need a new maf.

Either that or you have an air leak.

If you are using the stock intake, cracks normally develop on the accordion part near the throttle body. That would allow extra air in that hasn't been meetered.

s13 @ fullboost · 11-25-2008, 02:04 PM

ooooo Good reply zar you always help out I actually think that might be it in my case

aurora · 11-25-2008, 10:59 PM

i have an injen intake so thats not the case with me

i also checked for vacuum leaks and i even replaced some vacuum lines as a precaution

i want to believe the problem is the maf, but i guess i want a second opinion before i buy one...especially cause i already spent a good amount of money for parts that didnt need to be replaced

!Zar! · 11-25-2008, 11:04 PM

Well if it makes you feel better, I went through the same thing and it ended up being the maf.

Rapier46 · 11-25-2008, 11:14 PM

Mine did this at one time. I had an intercooler pipe off. Non turbo though? Hm.

mobilesuit818 · 11-26-2008, 01:14 AM

If you have a friend that has the same car, swaps MAF's out. that should do the trick.

If that doesnt rule it out, then it maybe a fuel pump issue.

I had the same issues years ago on my rolla, and it turned out to be a broken ground wire in the engine bay.

Hope that helps.

VQMaxFan · 11-26-2008, 03:06 AM

Maf is bad or possibly backwards.

punkrico · 11-26-2008, 03:26 AM

id say MAF too. When you unplug it the car goes into safe mode thats y it runs better

11-25-2008, 01:21 PM	#1
aurora Join Date: Nov 2003 Location: central nj Posts: 47 Trader Rating: (1) Feedback Score: 1 reviews	running better with maf unplugged? My sohc 240 hasnt been undrivable for over a month now, and ive been trying to figure out wats wrong, but i cant figure it out. With the MAF plugged in, my car starts just fine. The car doesnt idle since the revs drop down soon after the car starts. If i press down the throttle too fast, the car instantly dies. If i ease the throttle, i can keep the revs up high enough that the car doesnt die. However, once i hit 2000rpm, the car instantly dies. With the MAF unplugged, the car idles just fine. I can rev the engine fine as well. However, it bogs alittle after 2000rpm. Ive also succeeded in driving short distances Ive replaced the coolant temp sensor, ignition coil, sparkplugs, distributor rotor and cap, injectors, injector connectors. Im guessing i need to replace the MAF, but after searching, it seems like thats its never really the problem. Can you guys help me out?

11-25-2008, 01:42 PM	#2
s13 @ fullboost Post Whore! Join Date: Dec 2007 Location: St.Petersburg,FL Posts: 2,550 Trader Rating: (15) Feedback Score: 15 reviews	You know I am having similar problems right now so I would really like to see some good answers and maybe we can both fix our cars __________________

11-25-2008, 01:49 PM	#3
!Zar! Post Whore! Join Date: Nov 2004 Location: North Korea Posts: 14,579 Trader Rating: (27) Feedback Score: 27 reviews	Sounds like you need a new maf. Either that or you have an air leak. If you are using the stock intake, cracks normally develop on the accordion part near the throttle body. That would allow extra air in that hasn't been meetered. __________________

11-25-2008, 02:04 PM	#4
s13 @ fullboost Post Whore! Join Date: Dec 2007 Location: St.Petersburg,FL Posts: 2,550 Trader Rating: (15) Feedback Score: 15 reviews	ooooo Good reply zar you always help out I actually think that might be it in my case __________________

11-25-2008, 11:04 PM	#6
!Zar! Post Whore! Join Date: Nov 2004 Location: North Korea Posts: 14,579 Trader Rating: (27) Feedback Score: 27 reviews	Well if it makes you feel better, I went through the same thing and it ended up being the maf. __________________

11-25-2008, 10:59 PM	#5
aurora Join Date: Nov 2003 Location: central nj Posts: 47 Trader Rating: (1) Feedback Score: 1 reviews	i have an injen intake so thats not the case with me i also checked for vacuum leaks and i even replaced some vacuum lines as a precaution i want to believe the problem is the maf, but i guess i want a second opinion before i buy one...especially cause i already spent a good amount of money for parts that didnt need to be replaced

11-25-2008, 11:14 PM	#7
Rapier46 Zilvia Member Join Date: Oct 2008 Location: Calgary Age: 34 Posts: 260 Trader Rating: (0) Feedback Score: 0 reviews	Mine did this at one time. I had an intercooler pipe off. Non turbo though? Hm.

11-26-2008, 01:14 AM	#8
mobilesuit818 Zilvia Member Join Date: Jun 2003 Location: USA Posts: 269 Trader Rating: (2) Feedback Score: 2 reviews	If you have a friend that has the same car, swaps MAF's out. that should do the trick. If that doesnt rule it out, then it maybe a fuel pump issue. I had the same issues years ago on my rolla, and it turned out to be a broken ground wire in the engine bay. Hope that helps. __________________ Quality is not expensive, its priceless.

11-26-2008, 03:06 AM	#9
VQMaxFan Zilvia Junkie Join Date: May 2008 Location: Mobile AL Age: 35 Posts: 464 Trader Rating: (3) Feedback Score: 3 reviews	Maf is bad or possibly backwards.

11-26-2008, 03:26 AM	#10
punkrico Leaky Injector Join Date: Apr 2006 Location: memphis Posts: 126 Trader Rating: (3) Feedback Score: 3 reviews	id say MAF too. When you unplug it the car goes into safe mode thats y it runs better