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emericanz
09-12-2012, 04:54 AM
my rb20det swapped into an s13 will not idle revs up fine but no idle

timing is perfect and fuel is sending anyone got any ideas on what this could be? im gonna do a vacuum test and fuel pressure today.

baube
09-12-2012, 05:27 AM
hot or cold?

OneSicSilvia
09-12-2012, 06:17 PM
Sounds like a leak to me. Take some ether and spray around any couplers or the IC itself. Spray around any other holes that are plugged off to ensure there is no access un metered air being pulled in. If there is, the car will more than likely die at idle. I had a big leak in my intake after the MAF and the car wouldnt idle.

emericanz
09-12-2012, 09:40 PM
didnt get to test it today fixed some minor things on had to wait for my o ring for the tank came late and had to go so tomorrow ill test it. fuel pressure and ill smoke the intake up a bit. i feel like its fuel

i can run the car but as soon as i let off the throttle, she dies.
also unplugged the maf it dropped a bit and same with the o2 sensor so they seem to be working fine.

we did spray carb cleaner into it and it shot up but backfired alot.

hope this helps a bit. but ill def start spraying around areas for leaks.


also baube this is both actually i dont have the rad hooked up yet but i dont get my hands on the car 24/7 since it sits at the shop i work at. but ill try running it for a few mins it will heat up and same problem. no idle

SideSteppn
09-12-2012, 11:41 PM
I have the same issue, but with an s13 sr swap.. the previous owner of the motor (lived in japan.. i purchased from a local importer). we hooked up the intake today (brand new with new couplers) as well as the new greddy intercooler and piping. idles perfect without the z32 MAF plugged in, but obviously cant rev past 2k. when the MAF is plugged back in, the car dies out, unless i'm revving it up.

I also installed the swap with a fresh wiring harness from Wiring Specialties, and everything is hooked up right. However, we traced some wires on the previous harness that came with the swaped motor, and notice some "vampired" wires (meaning it looks like the previous owner was running a piggy back) and the previous harness was also already wired for a z32 MAF.

I'm unsure where to go next with this, and really dont want to shell out $1300+ on an engine management system, if there's an easier and more cost affective way to fix this... I'd buy a stock map and hook that up if i thought it would fix the issue.. the only thing with that is, the motor came with rb25 550cc injectors, Tomei Poncams with 256/260 intake/exhaust lift, bigger gt28 turbo, and who knows whatelse is done internally without pulling the motor apart..

the motor is in imaculent shape with all fresh gaskets, worked head etc. so i know things are done right.. when i give it gas and let the turbo spool (past the ideling/low throttle issue) the car pulls HARD..

ANY HELP would be appreciated, and i'm sure the guy that started this post would agree since it sounds like we're having the same issue..

emericanz
09-13-2012, 04:51 AM
bump on some help with this idle issue.

gonna run some vacuum and fuel tests today if possible.

emericanz
09-14-2012, 05:04 AM
fuel pressure test came up at 50psi while pump was on then dropped to 40psi.

also doing vaccum test on it today

finally need wire diagram for ecu

emericanz
09-28-2012, 11:52 AM
ok i need serious help on this!

the car is still refuseing to idle UNTIL i unplugged my maf and o2 sensor.
now ive been searching for info on this like crazy and im guessing i might have a vaccum/boost leak somewhere or maf &o2 are bad or the wiring is just screwed.. these are what im going to check also to give u an idea of whats done to my swap its...

everythings stock besides the wally 255 fuel pump and stage 2 clutch and splitfire coilpacks.

SideSteppn
09-28-2012, 06:26 PM
Im not sure if it will be the same for you, but...

With my SR i thought i was gonna have to take the head off to investigate more. I started, and got the valve cover off only to find my rocker arm chillin in the head... Boggled how it happend, but put it back in its place, bolted everything else up, started up and idled fine.. Problems fixed and its running like a raped ape.

Might not be the same for you, but worth checking out?

emericanz
09-29-2012, 04:33 AM
it cant be anything mechanical im base dealing with a wiring problem.

last night i got it to idle smooth by keeping the o2 sensor plugged in and not the maf

but when i would try n rev it up it jsut didnt know what to do with itself.

so now its just test the maf. if it checks out i got bad wiring and going to have to trace it all the way through....great -_-

bkt808
09-29-2012, 11:07 AM
Bad mafs.......

SideSteppn
09-29-2012, 11:53 PM
i thought i had wiring issues too.. just sayin..

doesnt take much to pop the valve cover off and check it out.. may take you an hour tops.. mine wouldn't idle, and eventually started sputtering.. since the rocker arm fell off, it was caugint the cylinder to act funny, as well not allowing the injector to funtion right. because of that it was dumping fuel into the cylinder as well as fowling the plugs.

if you've eliminated everything else, it would be worth at least taking a look. good luck!

bkt808
09-30-2012, 02:01 AM
i thought i had wiring issues too.. just sayin..

doesnt take much to pop the valve cover off and check it out.. may take you an hour tops.. mine wouldn't idle, and eventually started sputtering.. since the rocker arm fell off, it was caugint the cylinder to act funny, as well not allowing the injector to funtion right. because of that it was dumping fuel into the cylinder as well as fowling the plugs.

if you've eliminated everything else, it would be worth at least taking a look. good luck!

Rb's dont have rocker arms buddy:bow:

SideSteppn
09-30-2012, 09:07 AM
Welp.. Must not be the rocker arm then! :picardfp:

emericanz
10-01-2012, 04:45 AM
ive had the cover off periously to check the cam out because my cas was wobbleing but it was just the bracket and if it take you an hour to take the valve cover off on either side you should probably reconsider what your doing and call someone who does no offense and yeah theres no arms bud. and my issue is def maf related due to process of elmination and al ofthe tests i ran sorry but no.

SideSteppn
10-01-2012, 08:08 AM
U mad bro?

Just trying to help man, glad you found your problem, hope you fix it!:bigok:

if you notice the post before, i was corrected... I also said an hour for the COMPLETE job at most, meaning taking the valve cover off, checking stuff out, fixing the issue (if there was one), scraping old gasket replacing new gasket, spark plug o-rings and putting cover back on etc...

Again this suggestion was because of a similar issue i was having with my motor which is an sr. i was just offering some insight, not thinking it would fix your issue, but mearly sugesting another option.. As i found out previously by the other member, mine is more different from yours than i assumed.

When im messing around in my engine or head for that matter, its not about how quickly i can get it done, but more so how precise and efficiently i get it done. I take things slow and get them done right the first time ;)

Its apparent that you're not having the best day though, and still having an issue getting the motor running right. I hope you find a maf that works for you, and you're able to fix your ride. I wont offer any insight in your post anymore though so GL brah! No hard feelings!

SideSteppn
10-01-2012, 09:02 AM
ok ok one more thing.. The reason your car was running smooth with the maf unplugged is because your motor/ecu is running in "limp mode", and the reason you cant rev past 2500 with it unplugged, is because the motor isnt getting the proper air readings (amount of air) from the meter because its unplugged which causes it to bogg/cut back past a certain rpm..

I wouldnt be suprised if you replaced the maf and things were still not at 100% . Just sayin... But if so, you da man! ;)

Ok im done..

emericanz
10-02-2012, 05:02 AM
i can rev way past 2500 with it un plugged. i know what im doing when it comes to mafs and your information isnt totally reliable so now please leave my thread.

also non ofthis matters casue its pouring out coolant from the head on the intake side and dumping white smoke with a grayish tint. obivously i wouldnt have seen this before casue it never had coolant in it. so yeah im going to rip off the head etc etc thread is now useless

SideSteppn
10-02-2012, 08:12 AM
But wait... I thought it was wiring and not mechanical?? :doh::blah:

bkt808
10-03-2012, 03:53 AM
i can rev way past 2500 with it un plugged. i know what im doing when it comes to mafs and your information isnt totally reliable so now please leave my thread.

also non ofthis matters casue its pouring out coolant from the head on the intake side and dumping white smoke with a grayish tint. obivously i wouldnt have seen this before casue it never had coolant in it. so yeah im going to rip off the head etc etc thread is now useless
it shouldnt rev past 2.5k with the MAFS unplugged in limp mode

emericanz
10-03-2012, 04:45 AM
i cant see if it does but it def sounds like it revs past 2500 while unplugged but backfires etc

looks like it might be the intake mani gasket btw does anyone know ifthe coolant passages touch that gasket? plus i dont see a papergasket being mechanical.

i doubt its the headgasket consider the fact its pouring out of the intake mani and head like right between ill try to post a pic

SideSteppn
10-03-2012, 06:48 AM
it shouldnt rev past 2.5k with the MAFS unplugged in limp mode

^^^yup, already tried telling him that.. He's a professional though and apparently knows EXACTLY what 2500rpm sounds like without looking or having his gauge hooked up.. Must have learned it from Gone in 60seconds or somethin.. :smash:

Emericanz.. The paper that the gasket is made of OBVIOUSLY isnt mechanical itself, BUT the gasket goes in between a mechanical part (not a mechanical moving part) that you say is failing.. The gasket definately isnt a wiring issue.... Without that gasket, your engine is not working mechanically bud :doh:

How bout just taking your car to someone that knows what theyre doing... Like a real mechanic.. Just sayin

emericanz
10-03-2012, 11:58 AM
lolz why dont u just leave the thread brah and the coolant leak shouldnt be whats causing the no idle yes theres a leak between the head n mani and yes it should be pressurized n its not doing that but to casue a no idle hmmmmmmm yeah makes no sense it explains the white cloud of smoke behind the car but no idle? unless the cylinder where flooded and not getting any air at all possibly but the fact the car can still chug along and not detonate i doubt thats whats casueing it im 95% sure its the maf and therefore not a mechanical problem lolz it be the COOLING SYSTEM or did you not learn about what that is in your uncles back yard?

you dont understanf the problem so leave also my wiring is screwed gave the car to TWO different "MECHANICS" to do casue i was to lazy n busy to do so and look where it got me hmmm

and i obviously know what im doing if i can narrow the problem down myself to the maf so two on the chin to you buddy

plus if your so great why dont u get ur country boy lovin ass up here to pa n fix it for me master tech

SideSteppn
10-03-2012, 07:02 PM
:facepalm:

:jerkit:

Kids crack me up..

All i know is, my car.. that I myself built.. runs... and runs daaaaamn good..

Maybe you need a back yard uncle to teach you instead of the two mechanics you took it too ;)

Maybe you should just sell your car and find one thats already built and running hahahahahahahaahaha

emericanz
10-04-2012, 04:50 AM
hahahaha good one now gtfo of my thread skeeter

SideSteppn
10-04-2012, 07:17 AM
Nah im good, this is tooo entertaining