Jump to content
SAU Community

Recommended Posts

Ok ok, before you flame me, I have read the Power FC FAQs. This is an Apexi Power FC D-Jetro for and RB26/30 in an S14. Engine starts and idles fine with the stock ECU, plug in the Power FC, and it just starts and immediately dies. I have turned the boost control feature off. I am using 1000cc injectors and have set the injectors to 44%. I am using the GM 3 bar map sensors, which have not been calibrated in the hand controller because apparently I need a dataloggit. I have the signal wires of the map sensors going into pins 27 (black wire) and 35 (orange wire). I have checked all power and ground connections, all are ok. Anyone have any incite into this? Would be greatly appreciated.

The map sensor not being calibrated is the problem.

Being the sensor used to determine load how do you expect the power fc to know what's going on with the engine with it not calibrated?

Yuh, it's like hooking the PFC up to the bench vice in your shed and expecting it to work.

mine worked fine when I did this. but it had a random cough so I replaced it with a haltech

  • Like 3

I thought it should still start though as load is also determined by TPS input. And I thought it silly that the Power FC NEEDS to have those sensors hooked up and calibrated just to start and idle. But I guess with it being older technology, it is what it is.

What if a sensor goes bad when starring the car 300 miles from home? That would suck lol......

I thought it should still start though as load is also determined by TPS input. And I thought it silly that the Power FC NEEDS to have those sensors hooked up and calibrated just to start and idle. But I guess with it being older technology, it is what it is.

What if a sensor goes bad when starring the car 300 miles from home? That would suck lol......

Like any car if the main load sensor fails the car typically won't run.

It's nothing to with being old. Load is a function of the map sensor influenced by throttle position. how can you think it's silly it doesn't work without its main sensor?

The engine also determines fuelling based on its rpm input.

If that wasn't connected do you think the car would run?

;)

Edited by Ben C34

Just sell it and buy something more modern.. but the time you buy the cable and/or datalogit etc.. blah blah blah and find out you need inputs for your wideband/flex sensor/secondary speed sensor you'll just end up selling it anyway

  • Like 1
  • 2 weeks later...

Finally got a Datalogit installed and changed the MAP PIM scale and offset numbers on option 1. Changed to 6630 and 0 (off the top of my head) and she still just cuts off immediately after it catches during start up. Any ideas now?

I have had little luck getting my engines to start on the base maps for the d-jetro. I found it best to completely do away with the base map in the ECU, and start again from scratch. Its pretty easy to do once you get the engine to idle. To do that though you need to know how to set it up.

Turn on a watch in the datalogit, and watch Injector MS. Make note of what it is doing during initial starting and when it stalls out. See if it goes to <2ms or even zero.

Having a wideband O2 can help too, as you can see if it goes super lean before cutting out.

Finally there is the fuel/ignition lockout method. Set all your fuel base MS to 2.00ms for the 1200 RPM and below range, and ignition at 20 degrees for the same range. This will allow your MAP sensor to be ignored and essentially locks your fuel/ignition delivery with fixed values to allow you to get the car to idle.

Start the car, and note the O2 meter (if you have one). Increase the fuel MS for the locked out range gradually if need be (if it keeps stalling out). Once its running properly, you will be able to determine what the load point is that the MAP sensor will operate at when idling.

Then break out a timing light and set your base ignition to 20 degrees, and adjust your fuel again to get it idling nice. If you have no wideband, you can reduce fuel little by little for the idle load point while watching RPM. Keep reducing fuel while RPM increases until it stops increasing. Then add about 0.1ms.

Once you have it idling, you can adjust your MAP sensor Offset value such to put the idle load point at the second from the bottom load range. Turn on another watch, and monitor the PIM value. Use this value to modify the offset for the Map sensor to move the load point. Engines with stock cams will pull a -18inHG vacuum, so the second from the bottom load point is a good place to set it too. Larger cammed engines will have less vacuum, so set it at the 3rd load point for those.

my suggestion

1. perform DATA INIT

2. turn car off

3. turn car to ON, but don't start it

4. set map sensor settings via datalogit (or hand controller)

5. set boost kit off

6. check SENSOR SW CHECK and make sure no sensors are black highlighted

7. start car and perform self idle adjust process (this is documented in the FAQ)

then it should be stable and it should idle

note the self idle adjust is meant to run for 30 minutes......

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • The wiring diagram for the R33 RB25 is freely available, and is essentially the same same as most other RBs (just with differences as to which pin # does which job). To get the ECU to power up, you just need to provide power to the ECCS relay, and have the other power feeds that come in from the top left of the wiring diagram (wrt the ECU) that give perma power to the fuel pump relay, the ECU itself, etc etc, all connected. When you put power on all these it will just come to life. It's pretty clear from the diagram what needs to happen. Just follow the lines from the 12V + supply stuff in the top left over towards the ECU. I've even posted snips of such diagrams (not for vanilla 25, I think for Neo and 26) to various threads here in the last few months, talking about what it takes to get the fuel pump and FPCM up and going. Search these up and they will help get you started on doing the same with the vanilla 25 diagram. Hell, for all I know, I've done the same with that one in years past and have forgotten.
    • Yep...so unless someone posts up the answer you will need to probe from the ECU connector to the dash plug with a multi meter in continuity mode to trace the wires.  Note the ECU has multiple - and + (and across different key settings - Battery, IGN and Start) and most likely the power is fed from the connector(s) that is normally near the left hand headlight.
    • Thanks Duncan, I am actually just trying to get the Rb turning and running with the RB25DET S2 original loom itself  I am just trying to get it going outside the body and not thinking about the S15 or trying to match anything to the S15 loom at all I am only trying to see if anyone has done this and what pin they found to be the ignition trigger and ECU+/- on the dash connector, that's about it. Thanks  
    • Hi Guys, Does anyone know any aftermarket part numbers for a starter motor to suit the VQ25DET? I can find lots of alternative part number for the VQ35DE, which I assume would fit, but there is a lot of conflicting information out there. Thanks..
    • I don't understand how this hasn't boiled down to - Upgrade the turbo when you have everything required. ECU, injectors, fuel pump, turbo, etc. Do it all at once.  If you don't have everything required, just enjoy the car as it is and keep saving up your pennies. 
×
×
  • Create New...