200sx not starting everytime!!

[jemixter]

i tested battery voltage and it was 13.6v an tries to start but nothing.. engine spins . i have great compression.. injectors click and i have a spark but not starting.. then i put my battery booster charger thing on my battery and gave it more power and started right away.. everybody says my alternator is bad but its putting out 14.2v when running so it is good.. i thought my grounding were bad but i tested everything and even tested resistance between points and biggest i got was around 2 ohms so they should be ok. I dont know where to look next. can anyone help me

[PapaSmurf2k3]

Something may be going bad and needing more voltage to operate.
Try putting some fuel in a vacuum line or spraying some starting fluid in or something. Maybe the fuel pump isn't pumping enough.

[amc49]

I'd be looking at fuel pump too............When they go sometimes it shows at starts, they just don't wanna. Then suddenly they do. The boost may be jolting it into life.

[jemixter]

i have a adjustable fpr with gauge and its holding steady 3bar but ye okay maybe i still will try

[PapaSmurf2k3]

i have a adjustable fpr with gauge and its holding steady 3bar but ye okay maybe i still will try

Maybe the same deal with the injectors then. The increased voltage is bringing them to life?

If you crank under normal battery power and it doesn't start, are the plugs wet when you pull them out?

[jemixter]

it geta fuel even when not starting. i checked plugs and even with nistune and those injector open times were the same.. so i think my spar is not strong enought? i took all my vag coils out and tested and every one seemed to have good spark but again cant know if they have under pressure.. and one thing i noticed was when i charge my battery with booster to full 13.8v then it starts right away without charger but when i tur it off after idling a while and i got like 13.6v then it cranks the same but not firing up.. so it always starts first time when full charge i tested my grounds and injector voltages ja everything but no luck. i think i have to move to a some huge truck battery to get it started

[PapaSmurf2k3]

Are you running a NISTUNE ECU or factory one?

[jemixter]

nistune

[PapaSmurf2k3]

If you've got access to a factory one, can you throw it in there to see if it has the same problem?
Not sure how big your injectors are, but you may need to scale back on your fuel pressure to get it to run.

[jemixter]

i tried with stock one and same thing starts only with booster.. runs super rich with that because its scaled to stock 370 injectors.. i have 800cc sard injectors and my nistune ecu is mapper for my setup:) it made 407whp at 1.6bar gt3076R

[jemixter]

and it runs well but only not starting

[PapaSmurf2k3]

I mean, it sounds like you just need to figure out what it isn't getting (or getting too much of).
If you pull the fuel pump fuse after you crank and it doesn't start, does it eventually start up? Will it start if you use starting fluid? Will it start if you pull a vacuum line or 2?

[jemixter]

i tried few things today and i noticed that my injectors wont pulse when not full battery or on booster.. then i tried my stock injectors with low battery.. like 11.5v the still fired.. so i think my sard 800cc inkectors just need more voltage to fire? next thing i am gona do is check how much voltage drop on starting..

[jemixter]

not much voltage drop on staring and runs like charm. with stock injectors.. wtf do i do with those 800cc if cant get car started with those

[PapaSmurf2k3]

I thought you said the plugs were wet with fuel after a no-start event?
Anyway, you can try adjusting your injector dwell or pulse width via the ECU. Might just need more time to open the valve with lower voltage.

[amc49]

13.6 volts is NOT a battery voltage, it reflects surface charge which is not real. A battery can only read up to 12.8 volts in and of itself. You may just have a bad battery. Let the car sit overnight (over 8 hrs.) with no starting or charging and check the voltage the next day, if anything less than like 12.3 volts the battery is a problem.

Injectors firing at 11.5 volts is worthless as well, they will fire lower than that but in no way will they be metering correctly and you cannot see that.