FUEL PROBLEM?

[got2b240]

Running a s13 redtop in a s13 hatch 5 spd

Since I got it the motor has been running bad and I was wondering if these are the cause of some problems:

running the E5 ecu for a redtop?

to stop the motor from running like crap (misfiring and sputtering under acceleration) I semi-clamped the fuel return line after the fuel pressure regulator

using 300zx fuel filterwalboro 255lph supposedly being usedsohc MAFS, took one out of my other 240, also got the car with a cut wire grounding mafs, fixed it

when I unplug the mafs the car no longer misfiresi believe to be a bad o2 sensor

a sewing machine noise comming from under valve cover

smaller pipe comming from turbo to FMIC then the one going up into the intake (3" going up)

seems like the car needs to run richer than it is? Maybe the kid wired something wrong?

ignitor chip is just dangling from its harnesses, and not mounted

i set timing to 15, set tps to .45 at idle and it goes to 4.13 at WOT

maybe the plugs are gapped wrong?

in 1st and 2nd gear, boost will max at 11 and 3,4 and 5 will boost to 13?

I have spent endless days trying to conquer this problem, but I am stumped and getting frustrated! I would appreciate help or even pay someone to look at my sr setup who is familiar with them. I live on Long Island in NY. cell 631-875-1937

thank you for any help-Chris

[DriftS14]

I run an E5 ecu on my redtop. You could erase that from your list.

[got2b240]

ok cool, I just hope the kid wired it up right. how does your car run?

[DriftS14]

It runs excellent. (knock on wood) Another thing you could erase is the ignitor dangling. Mine is too

[got2b240]

did you ever have a poping/misfiring problem with your motor?

[DriftS14]

Nope, never (I don't want to say it too loud though). I did smash my intercooler into the driveway once. The boost leaks it caused made the car run pretty crappy. You might want to check for those. Do you have a way of taking any video of what you are talking about? I'm a lot better at diagnosing from listening.

[got2b240]

ummm can i call you?

[got2b240]

brb im going to go outside and check some more **** out

[SpeedRacer1]

There are many places to start looking. I ran an E5 ECU on a redtop for awhile, it ran a little bad, but it was lean not rich so thats probably not your problem.

My best guess right now might be that the power wire to your O2 sensor is not connected. You mentioned some kid wired it up, well the heavy throttle faq tells you to give the O2 sensor (brown wire by the batter) a 12 volt source, but doesnt specifically say any wire. So maybe he forgot to connect it.

When the O2 sensor is disconnected, the car runs EXTREMELY rich when driving, while at idle it runs much leaner than normal.

TPS is a hard one to judge since every ECU can have slightly different voltages, its very sensitive. It can cause some serious problems if its off by barely any voltage.

Igniter chip doesnt need to be mounted.

Stock boost is 7 psi, do you have a boost controller? Are your vac lines hooked up properly.

[got2b240]

im not sure if the vac lines are hooked up properly, off the manifold, the top left is going to a tee at vac gague and fpr, the one on the right is going to the BOV, on the bottom is sealed off well. I had to richen the ratio out by slightly clamping off the fuel return line after the fpr (which i replaced with used one) going to the tank. Otherwise without that the car misfires at idle and studders upon acceleration in both boosting and regular non-boost driving. I set tps to .46 volts at idle and it goes up to 4.3 at WOT. I dont get any voltage from the o2 sensor harness comming from ecu, isnt that strange...I guess i have to trace the wire going to the source tomorow. I know to test the o2 sensor you have to ohm it out, but what is the exact procedure upon doing it, what resistance am i looking for?

I have a manual POS boost controler that I had problems with before, should I try running stock boost for now to be on the safe side?

Im thinking about saving up for a Apexi Power FC, I read up on it it seems great!

[Nismo_Freak]

when I unplug the mafs the car no longer misfires

You have a bad MAF ... replace it and you will not have this problem.

i believe to be a bad o2 sensor

O2 does not operate under WOT situations, ECU's high map, or when the car is idling. If it was bad you would not be getting misfiring and bucking you would just have an overly rich mixture while at partial throttle.

[got2b240]

thank you nismo freak, I will try this and let you know K+ for that help

[Nismo_Freak]

thank you nismo freak, I will try this and let you know K+ for that help

Np. also check the MAF's connection and wiring.

[got2b240]

yea, the ground for the maf was cut/ripped. Fixed that. Fixed the no power going to the o2 sensor, and discovered that my ECU is fried!! and wrong ecu btw.