s14 sr20det won't rev past 2800 rpms - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

Options13 · 08-31-2010, 09:12 PM

ok so i'm sooo close to finishing this swap. i just need a little guidance..

i got an 89 240sx with an s14 sr20det. and i went to start it today for the first time, it took a little bit of cranking.. probably about 5 seconds, i started it, and it ran good, idled good, no smoke, sounded good, and everything, it just wouldn't rev past 2800 rpms... and when i would go to shut it off, and try to start it again, it wouldn't start, at all.. so i take off the maf, and clean it with cleaner, and put it back on, it started up, still didn't rev past 2800. so i shut it off, and it didn't start again... its almost as if i have to wait a period of time before i can start it again...

what does this sound like to you guys? my friend was telling me my ignitor could be bad...

buentellomma · 08-31-2010, 09:23 PM

check the wiring on the mafs, also you could have a bad one.... try and find a known working one and swap it on. trouble shoot from there

sidedrifts13 · 08-31-2010, 09:39 PM

check your tps i had the same problem, also check to see if you are getting power to you maf and check all your grounds make sure you sand down to the metal where the grounds bolt up

Options13 · 08-31-2010, 09:41 PM

alright, i'll check that out tomorrow, what was wrong with your car? TPS was bad? so you just replaced it?

sidedrifts13 · 08-31-2010, 10:07 PM

my tps just needed to be set/adjusted, check you wiring on the maf and see if you are even getting power most likely its your maf so start there, just double check to see if you are getting power to it...MAF voltage should be 12v on the power wire and 5v on signal wire...adjust your tps to .45v to .55v, another thing you can do is check for codes on your ecu

Quote:

Originally Posted by Options13

alright, i'll check that out tomorrow, what was wrong with your car? TPS was bad? so you just replaced it?

240sxfamily · 08-31-2010, 09:54 PM

Its the Maf, wiring or the maf. try unplugging the maf and doing it. Keeping the maf on the car just unplug it while the cars running. see whats up. If not then check all the wiring for the maf. it IS that. This has left me stuck on the side of the road so many times..because i always ghetto it backtogether and I say..I'll fix it when i get home..that never happens.

pitbull287 · 08-31-2010, 10:28 PM

I had a neo computer once and it did that to mine i had to reset the computer.

Options13 · 08-31-2010, 11:09 PM

a neo computer? i have the black WC ecu, it didn't come with a diagnotic light from the factory i guess

teamsprock · 09-01-2010, 09:06 AM

Sounds like its in limp mode, as said above check the wiring to the Maf. Then check voltage on the CTS and TPS. I'd also pull the plugs just to make sure its not running so rich its fouling out plugs and keeping the engine from being able to free rev. Once you check those things let us know and I can make more suggestions if its not fixed yet.

Also what MAF are you running? DO you have any SAFC or anything that you can monitor the MAF voltage as well as TPS voltage?

Options13 · 09-01-2010, 03:17 PM

my KNOCK sensor reads 1.7v or something like that, but in the process of findgin out, i accidentally yanked the white wire out, am i able to just push it back in ? and is it normal for the black wire to just end in the middle?

also checked my TPS, 0.7closed 4.3 WOT

unplugged my CAS, and i heard something shut off, i think it was the injectors, so i know that works..

THEN i checked my maf, its getting no power at all, the middle wire is a ground right? white is signal, and what is black white? either way it has to be my wiring to my maf, no power what so ever.

buentellomma · 09-01-2010, 03:28 PM

trace your wiring back until you find where your not getting power at, also make sure its not wired backwards

Options13 · 09-01-2010, 09:50 PM

fixed the revving problem!! started the car up today, it reved nicely, and idled really good, a/f was also perfect.

the thing is.. the maf issue didn't fix my starting problem, after i shut off the car, i tried to start it again... and it didn't start.... sound like an ignitor to you guys? i mean, the car was running perfect!

buentellomma · 09-01-2010, 10:15 PM

what was the issue ?

Options13 · 09-01-2010, 10:24 PM

the b/w wire to the maf was disconnected about in the middle, so i just re-soldered it..
i let it run for about 3 minutes, reved it, a/f was good, vac was good....

i turn the car off, then i try to start it again, it just keeps cranking.... i don't understand what the cause of this could be? i heard an ignitor either works or doesnt...

08-31-2010, 09:12 PM	#1
Options13 Nissanaholic! Join Date: May 2007 Location: OR Posts: 1,825 Trader Rating: (43) Feedback Score: 43 reviews	s14 sr20det won't rev past 2800 rpms ok so i'm sooo close to finishing this swap. i just need a little guidance.. i got an 89 240sx with an s14 sr20det. and i went to start it today for the first time, it took a little bit of cranking.. probably about 5 seconds, i started it, and it ran good, idled good, no smoke, sounded good, and everything, it just wouldn't rev past 2800 rpms... and when i would go to shut it off, and try to start it again, it wouldn't start, at all.. so i take off the maf, and clean it with cleaner, and put it back on, it started up, still didn't rev past 2800. so i shut it off, and it didn't start again... its almost as if i have to wait a period of time before i can start it again... what does this sound like to you guys? my friend was telling me my ignitor could be bad...

08-31-2010, 09:23 PM	#2
buentellomma Zilvia Junkie Join Date: Mar 2010 Location: Goodyear AZ Age: 39 Posts: 480 Trader Rating: (6) Feedback Score: 6 reviews	check the wiring on the mafs, also you could have a bad one.... try and find a known working one and swap it on. trouble shoot from there

08-31-2010, 09:39 PM	#3
sidedrifts13 Nissanaholic! Join Date: Jul 2006 Location: LOS ANGELES Age: 41 Posts: 1,883 Trader Rating: (29) Feedback Score: 29 reviews	check your tps i had the same problem, also check to see if you are getting power to you maf and check all your grounds make sure you sand down to the metal where the grounds bolt up

08-31-2010, 09:41 PM	#4
Options13 Nissanaholic! Join Date: May 2007 Location: OR Posts: 1,825 Trader Rating: (43) Feedback Score: 43 reviews	alright, i'll check that out tomorrow, what was wrong with your car? TPS was bad? so you just replaced it?

08-31-2010, 09:54 PM	#6
240sxfamily BANNED Join Date: Aug 2009 Location: phillyy Posts: 705 Trader Rating: (2) Feedback Score: 2 reviews	Its the Maf, wiring or the maf. try unplugging the maf and doing it. Keeping the maf on the car just unplug it while the cars running. see whats up. If not then check all the wiring for the maf. it IS that. This has left me stuck on the side of the road so many times..because i always ghetto it backtogether and I say..I'll fix it when i get home..that never happens.

08-31-2010, 10:28 PM	#7
pitbull287 Join Date: Jun 2010 Location: georgia Age: 38 Posts: 14 Trader Rating: (0) Feedback Score: 0 reviews	I had a neo computer once and it did that to mine i had to reset the computer.

08-31-2010, 11:09 PM	#8
Options13 Nissanaholic! Join Date: May 2007 Location: OR Posts: 1,825 Trader Rating: (43) Feedback Score: 43 reviews	a neo computer? i have the black WC ecu, it didn't come with a diagnotic light from the factory i guess

09-01-2010, 09:06 AM	#9
teamsprock Zilvia Addict Join Date: Sep 2006 Location: Billings Age: 42 Posts: 636 Trader Rating: (8) Feedback Score: 8 reviews	Sounds like its in limp mode, as said above check the wiring to the Maf. Then check voltage on the CTS and TPS. I'd also pull the plugs just to make sure its not running so rich its fouling out plugs and keeping the engine from being able to free rev. Once you check those things let us know and I can make more suggestions if its not fixed yet. Also what MAF are you running? DO you have any SAFC or anything that you can monitor the MAF voltage as well as TPS voltage?

09-01-2010, 03:17 PM	#10
Options13 Nissanaholic! Join Date: May 2007 Location: OR Posts: 1,825 Trader Rating: (43) Feedback Score: 43 reviews	my KNOCK sensor reads 1.7v or something like that, but in the process of findgin out, i accidentally yanked the white wire out, am i able to just push it back in ? and is it normal for the black wire to just end in the middle? also checked my TPS, 0.7closed 4.3 WOT unplugged my CAS, and i heard something shut off, i think it was the injectors, so i know that works.. THEN i checked my maf, its getting no power at all, the middle wire is a ground right? white is signal, and what is black white? either way it has to be my wiring to my maf, no power what so ever.

09-01-2010, 03:28 PM	#11
buentellomma Zilvia Junkie Join Date: Mar 2010 Location: Goodyear AZ Age: 39 Posts: 480 Trader Rating: (6) Feedback Score: 6 reviews	trace your wiring back until you find where your not getting power at, also make sure its not wired backwards

09-01-2010, 09:50 PM	#12
Options13 Nissanaholic! Join Date: May 2007 Location: OR Posts: 1,825 Trader Rating: (43) Feedback Score: 43 reviews	fixed the revving problem!! started the car up today, it reved nicely, and idled really good, a/f was also perfect. the thing is.. the maf issue didn't fix my starting problem, after i shut off the car, i tried to start it again... and it didn't start.... sound like an ignitor to you guys? i mean, the car was running perfect!

09-01-2010, 10:15 PM	#13
buentellomma Zilvia Junkie Join Date: Mar 2010 Location: Goodyear AZ Age: 39 Posts: 480 Trader Rating: (6) Feedback Score: 6 reviews	what was the issue ?

09-01-2010, 10:24 PM	#14
Options13 Nissanaholic! Join Date: May 2007 Location: OR Posts: 1,825 Trader Rating: (43) Feedback Score: 43 reviews	the b/w wire to the maf was disconnected about in the middle, so i just re-soldered it.. i let it run for about 3 minutes, reved it, a/f was good, vac was good.... i turn the car off, then i try to start it again, it just keeps cranking.... i don't understand what the cause of this could be? i heard an ignitor either works or doesnt...