DriftWood240

Hello...i'm new to this forum, and after reading a few posts i felt this was a good place to ask for help. I did a SR swap into my 90' 240sx a few months ago and currently have a few bugs to work out. First of all, I'll describe the setup of my motor to better aid in the answering of my questions...

1993 Red Top SR20DET
Stock side mount intercooler (with BOV reciculating into the intake)
Blitz downpipe
2.5 inch cat back piping to Turbo N1
Spec stage 3 clutch
Stock KA24E radiator
Stock KA24E fuel pump
Stock KA24E fuel filter
7psi. boost
Stock everything else on motor :P

After a few months, my car still has problems idling. I've tried adjusting the screw on the AIV...and nothing. The car will idle for about 30 seconds after driving and the vaccum will be at 20...but after a while the vaccum starts dropping which causes the revs to start dropping, ultimately leading to the motor dying a shaky and violent death. Could it be a vaccum leak? Also, on the ecu there's a knob that says something about idle in japanese (thats all i can make out...i dont know too much japanese)...i turned that before the car was up and running...and was wondering if that could be a problem?

Another problem i have is starting. At first the car started fine every time...but now i find it struggling with cold starts. I'll crank it for like 2 seconds and it wont start...i let the fuel pump prime for a few seconds each time i try. On about the third crank the car will sound like its trying to start so i give it some gas...the motor shakes and the RPM's bounce from 0-300 about until the car finally starts. Could this be the Fuel pump or Fuel filter?

One last question...what is the normal running temp. for the SR?

Sorry for the long post...any help would be greatly appreciated...

Thanks,
Andrew

drifterJERRY

replace that fuel filter with a z32 one. (cheap and easy).

does the car motor run after you start it and give it gas? if no. replace pump. if yes, the future should involve putting a new fuel pump in your car(walbro or whatever...better than old stocker).

i would check everywhere for vacumm leaks and then check my timing/idle per heavythrottle.com.

the starting thing has a relation to one of the above problems.

ive heard from 165-190F depending on style of driving. i am at the lower limit.

the external knob on the computer means that someone has either put an aftermarket ecu in there or chipped it. it is used to advance the timing iirc. take a picture of the knob and ecu and we can better diagnose this.

240dreams

i would def say fuel filter. you might even feel an increase in rev speed from the z32 unit.

Fabrik8

I know the KA24E ECUs have an idle knob on them from the factory, the SR20 ECUs might too.. There is a little hole in the side of the ECU, with a slot end pot (variable resistor) that can be turned for idle control.
If it helps you any, the KA24DE that's been swapped in my 240 has a vac leak somewhere and it dies a shaky violent death too. I don't care though, I'm getting an SR swap, and I don't need to drive it at the moment anyway.. But anyway, I'd look at vacuum leaks.

DriftWood240

ok...i'm gonna try to change out the fuel filter this week. also..i think the ECU is stock but i'm not too sure...i'll try to get a pic of it.

where should i check for vaccum leaks at? the whole intercooler setup is fine..no leaks there...and no leaks at the throttle body. but there is a hissing sound by the fuel rail when i rev it...could it be a vaccum leak or just the injectors shooting fuel?

OH!!! and does anyone have a drivers side window for sale? my car got broken into and they shatter the glass

thanks for the help!~

eng

The adjustment knob is on stock ECUs.

The vacuum leak could on one of the hoses coming from the intake manifold if you hear it around the fuel rail. You might have just forgot to plug one of them up that you're not using.

DriftWood240

alright...i put on a FRAM fuel filter for the 95' 300zx...and my car runs the exact same. haha. planning on putting on the fuel pump in a couple days...hopefully that will fix it...i'll also be checking if there is in fact a leak by the fuel rail...thanks.

musicmaniac

id bet on the iacv(aac) valve is dirty i had the same problem on my dohc ka and it fixed it lickity split

ScrewD03

and how about replacing the fuel pump that would ix it... give it more fuel

sepulchral

you should have put a walbro 255 litres per hour in before the swap... you don't want to damage the motor, well actually youll be fine as long as you have kept it at stock boost.

do that it and if that doesnt work then run 3 cans of BG 44k fuel system cleaner on a full tank of gas