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garagelu
07-21-2008, 05:43 PM
My head has been hurting over this problem that I have had for the past few days. Today I finally made some headway. So my engine is just cranking and not starting at all. I checked spark, timing and today I checked if my injectors are firing.

I pulled the fuel rail and cranked the car with the fuel rail out. I find that all 4 injectors are not spraying. I then check if I am getting a 12v power to the injectors connector. So I turn the key to ON and probe the injector connector. Since the ECU just pulses the ground, it should have power to the plug. I even crank it with the test light in and nothing. So obviously my ecu is not sending the signal to the injector.

So now I am wondering what the source of this problem could be. I have a power fc and I have never really heard of anyone having problems with them.

Does anyone else know what I could do to get to the source of this problem?

brokeAs240sx
07-21-2008, 05:46 PM
Was teh car ever working while you had it? i.e. before you did something? You need to give some history...

i.e. do you have this working w/ a stock ecu?

w/o any info as to when this car was last working, it could be anything from a wiring issue to a bad power fc to lord knows what.

garagelu
07-21-2008, 05:54 PM
The history behind this. I made a 800 miles trip with this car only a day or two before problems started coming. Drove the 800 miles with not one problem. I have been running the same power fc for about 2 or 3 years now.

http://zilvia.net/f/showthread.php?t=203364&highlight=bucking

Here is the problem I had the day after. With this problem, I could still crank it and it would run.

After this problem happened I started to do some basic diagnostics like pulling the valve cover to check timing, replacing spark plugs, checking the coil pack to see if they are firing, and etc.

After I put everything together it just cranks and cranks with no sign of even trying to start.

motronic
07-21-2008, 07:49 PM
Did you check if you are getting spark at all? if not getting spark I would check your CAS to see if it is working and the timing is right. If there is no signal from CAS the engine would just crank and would not spark or injects.
If you have PFC I assume you have commander so you can do basic check such as MAF voltage, coolant temp etc.

Z U L8R
07-21-2008, 08:33 PM
that's good advice from motronic. is your power fc turning on at all?

Dave

garagelu
07-21-2008, 09:31 PM
It is definately getting spark so I know the CAS should be good and my coilpacks and ignitor are good. And yes my power fc is turning on.

Here is an update: Tonight I swapped ecu with a friend. The only difference is the his is a completely stock sr20 and mine has 550cc injectors, 300zx maf, and 2871r.

1) Here is what is confusing me. I checked to see if he has power to the injector plug with my power fc and there is 12v power. But then I unplug the ecu and check the 12v power at the injector and there is still power. So where does the injector get its 12v source from. Obviously not the ecu. Ecu probably just controls it.

2) Also my second questions is that if a power fc tuned for a bigger setup than stock, will it still somewhat run on a stock setup. I couldnt get my friends car started with my tuned power fc. I dont think this is really relevent. I really just need to figure out where the injector gets its 12v source from.

Anyone know? My car is a 1995 s14.

garagelu
07-22-2008, 02:51 PM
Does anyone know where the 12v wire that runs from the 4 injectors ends? I know the grounds go to the ecu but I need to know about the power wire.

garagelu
07-22-2008, 06:58 PM
Can someone check continuity for me on your own car. It would be best if you had a s13 sr20det wiring harness.

I need someone to check continuity between the 12v red wire on the injector plug and the blue ECCS relay right next to the ecu. All I am doing here is making sure that is the right wire that powers the injector. According to the wiring diagram, it is correct but I want to double check.

The relay should have 2 red wires, 1 red/black, and 1 black/white. Check from the plug to either one of the 2 red wires. Someone PLEASE do this for me. I am getting closer and closer to the source of my problem.

Maverick06xx
07-01-2018, 03:43 PM
Can someone check continuity for me on your own car. It would be best if you had a s13 sr20det wiring harness.

I need someone to check continuity between the 12v red wire on the injector plug and the blue ECCS relay right next to the ecu. All I am doing here is making sure that is the right wire that powers the injector. According to the wiring diagram, it is correct but I want to double check.


The relay should have 2 red wires, 1 red/black, and 1 black/white. Check from the plug to either one of the 2 red wires. Someone PLEASE do this for me. I am getting closer and closer to the source of my problem.

Did you ever figure this out

garagelu
08-12-2018, 06:39 AM
Did you ever figure this out

This was back in 2008 and I actually still remember what happened. The wiring going to the injectors corroded and there was actually a break in the wiring. I think I re-soldered it and it was good to go! Chasing it down was the most difficult part.