R32 Ap Engineering Powerfc Pics

[Sydneykid]

Gary (Sk) , what are your opinions of the AP PFC and this air temp probe business ?

Cheers A .

Sorry, I have no straight forward answers, I did a lot of the early RB stuff on other people’s cars. So I didn’t have the opportunity of finding out the whole story in some cases.

On my R32GTST I have a genuine RB20DET Power FC that I bought second hand from NZ around 4 years ago. So there is no doubt it is an “old” one. I have used a Boost Control Kit with it from about a year after I got the PFC. The map sensor plugged (3 pins) into the side of the PFC and I used the boost control solenoid pin outs (as per the RB26 ECU pin out diagram) to power the BKC solenoid.

At the time I did this, I was told that the RB20 PFC (R32GTST) was just an RB26 PFC (R32GTR) with a few changes. Since the BKC worked when plugged into the RB26 pin outs I had no doubt at the time that this was true.

Moving on to the Inlet Air Temp sensor, I got an RB26 inlet air temp sensor working on someone else’s R32GTST fitted with a PFC. I simply ran the wires from the sensor to the ECU, copying the water temp sensor wiring logic (positive supply and negative sensor output). Which I think is where Paul had problems as it seems he got the polarity wrong (confused the + and –) and fried his PFC.

The problem is I don’t know if it had an RB20 or an RB26 PFC. I always assumed that it had an RB20 PFC (same as mine) but I can’t guarantee that was the case. The car was stolen and recovered some time later with no PFC (and several other things missing) so I can’t go back and check it.

There is another complication, I knew nothing about Datalogit (maybe it wasn’t even available) when this car was tuned. A guy from NZ tuned it using “some software” on a laptop. Looking back I suspect that it was Power Excel as the screens were nothing like Datalogit. Maybe it was an early version of Datalogit, I don’t know.

I have yet to do the Inlet Air Temp sensor connection on my own R32GTST, it won’t be that hard as the RB26 plenum (on the RB31DET) has a working sensor in it. Once I have done that I will know for sure whether it works using a guaranteed RB20DET PFC.

cheers

[Cubes]

Yes I think Paul's experience has scared a few of us including myself.

Its interestering how pauls' r33 only damaged the actual track, I wouldn't have thought the small voltage received from the IAT sensor would have been able to do such damage to a simple track.

There is no doubt the RB20 and even RB25 PFC's have the a track running around the pcb from the IAT pin 57.

Its also interesting to note that the ONLY ecu that uses pin 57 is the rb26 ecu, it may be very well possible the rb20 and 25 ecu's are actually based on the rb26 to cut on individual production costs. Simply tweak them a little to suite the application.

I will be looking in to this more. Time to pull the pfc out again and take some more pictures so I can see what pins are connected.

[paulr33]

haha my experience was funny but damn it sucked at the time. anyway heres a recap of what i did.

1) find water temp sensor wire

2) cut it

3) turned key to ACC and verfied water temp under monitor was --- (made sure i cut the right wire)

4) turned car off

5) ran the water temp signal to the airtemp wire (as per the rb26 loom)

6) turned car to ACC

7) airtemp was --- still

8) turned car off

9) tried adjacent wire next to airtemp (in case they moved it)

10) turned car to ACC

11) clicking relay, garble on hand controller

12) turn car off

13) replace fried water temp sensor

14) fix burnt track on FC

15) all back to normal

now i know my downfall was tapping onto the adjacent wire in a bit of a hit n hope method and it died honkey

but hey, i tried

moving along, i dont see how the Air temp plugin method could work if there is no AIRT under SENSOR SW check

rb20 ap engineer does not have AIRT under sensor sw check so i dont see the logic in how it would work?

why would ap remove the sensor from SENSOR SW (given there were are plently of empty *** spots so it wasnt a shortage of outputs on the screen)

but leave the code logic in the FC to still read the sensor and bring it up under MONITOR and make the airtemp correction table useful.

i guess on the other end of the scale it makes sense, i mean why did they leave AIRTEMP on the RB25 version if the car never had an airtemp sensor

[Cubes]

lol.. I didn't realise you tried the adjacent pin..

Knowing that I've grown some balls to give this a shot.

Does the IAT sensor output the same voltage as the water temp sensor?

I remember after that you replaced your water temp sensor? Maybe it was buggered before? Maybe the only way to view the output IAT is datalogging?

[paulr33]

yeah i tried the adjacent wire in case i had gotten it wrong

at least im pretty sure i did, or i could have also possibly looped two wires on the FC loom as I had a few exposed wires and the water temp was on a pin probe type stick and i was tapping it into the pin sockets, so i could have ran it across two pins

the water temp sensor fried itself

when i put the stock ecu back in it reported (nissan datascan) water temp as -55 deg (some silly figure) the car also wouldnt start. i had fuel pump, spark (tapping on screwdriver) and it was trying to crank but just wouldnt. loaded up datascan it reported water temp as -55 deg. so i got a 2nd hand ca18 sensor and it worked fine. car worked, and FC worked once track was fixed.

im guessing the sensor is in the same voltage range, someone with an RB26 FC could tell u what SENSOR SW looks like with AIRT working. my water temp was working fine before i tried this experiment and was always showing normal ish results on MONITOR and car starting always.

[paulr33]

i would see no reason (that seems logical anyway) why airtemp would appear under datalogging logs and not under MONITOR. datalogit logs simply snapshot the MONITOR sensors and SENSOR SW sensors at regular intervals and dump the values. youll notice they plot some sensors twice and they have different values despite being the same thing. i think the precision isnt as quick as they would like it to be, thanks to vbrun time crap

[paulr33]

anyway moving along, IMHO dont try it, you are likely to make it go bang and regret it, unless you can really justify to yourself its going to work and AIRT is a sensor under MONITOR. on an BR26 (logs i have) airtemp hovers near 55deg for most of the time. under datalogit airtemp correction it takes out i think from memory -2 deg timing for 50 and -3 or 4 for 60 and so on.

so it does simply backing off timing as intake temps rise but its certainly not a show stopper, well that i see anyway.

the main thing i noticed, it doesnt advance timing when its colder, ie AIRTEMP of 12 doesnt yeild +6 deg IGN timing, only retarding when hotter, which i guess is simply the same thing. just dial in stacks of tming on the MAP and then when its nice and toasty intake temps take out timing as needed.

[paulr33]

whilst flicking thru the datalogit forums on some guys trying to get boost pressure displayed without buying the complete boost kit, and only buying the map sensor and wires i came across this (from steve, author of datalogit);

Remove the Power-FC from the car, and power it up on a bench.

Connect 0V and 12V from PSU.

With a 1.5V battery, connect -ve end to PSU 0V, and the +ve end to a

1K resistor (which will prevent possible damage to Power-FC by

limiting current). Touch the free end of the 1k resistor to each pin

on the Power-FC while logging, until you see the air temp change.

[paulr33]

sorry it was in relation to airtemp testing

http://sports.groups.yahoo.com/group/FC-Da...er/message/3403

[Swiper the Fox]

I wonder if they do powerfc upgrades...you know...launch control etc..

Yeah...love to be able to reflash mine with PRO software...two step rev. limiter....oh yeah!

[RB30-POWER]

yeah stuff trying to launch a manual without a good two-step.

microtech actually does this preety good, it has a full two-step map, you set the rpm limit (ign cut), add more fuel, retard timing and presto, you are launching on boost with your manual without a complicated antilag setup.

better then the basic ecu two-step setups that only do a ignition or fuel limit cut.

how does the pro software models do the two-step, any idea how good it is?

[paulr33]

do you mean the apexi powerfc PRO version to suit RB26?

when the car is at 0km/h the rev limit changes to an alternate RPM setting under SETTING, RPM which can be set to whatever.

so that when the car is stationary and you hold the pedal to the floor it will sit at the alternate RPM setting, ie if its set at 4300rpm then you floor it and the car isnt moving the rev limit will be bouncing at 4300rpm and be pegged there. as soon as you start moving, the rev limit returns to normal rev limit say 7800rpm

it also does spark cut instead of fuel cut at redline

[shaunmlawry]

Hey guys,

I am looking at putting an aftermarket computer into my rb20 cause my fuel economy is very shit.

I was wondering if the new r33 powerfc's can be modified the same way to work with the rb20?

And if i were to plug in the r33 powerfc would my car start up and allow me to tune it?

Thanks

Shaun

[paulr33]

the powerFC FAQ covers how to use the rb25 ecu on rb20

http://members.dodo.com.au/paul/docs/power...powerfc-faq.htm

proceed at your own caution however, it may have unexpected side affects

[shaunmlawry]

Thanks

Has many people done it this way?

What would be the worse i could do to the powerfc?

[shaunmlawry]

Also can you calibrate the tps voltage with a powerfc?

I have a modified one in mine and it has a different voltage range

[paulr33]

a few people i think have done it, i am yet to see any confirmed people that have done it. its not to say it hasn't been done, its just to say i havent heard from them. i think it would be easier to use the rb26 powerfc instead. worse you could would be to fry the ecu or have the engine check light on always if you use the rb25 pfc (as VCT wont be detected)

[paulr33]

not that i know of, theres nothing in datalogit or the hand controller for it.

how is your stock ecu working if its different voltage?

[shaunmlawry]

not that i know of, theres nothing in datalogit or the hand controller for it.

how is your stock ecu working if its different voltage?

I have placed a resistor in it but it doesn't go all the way up to 4v on full throttle. Full throttle is only 3.3 volts. So i don't have it wired in at the moment

As for the r33 powerfc if anyone has done this with success can they please post what had to be done, and if they have had any hiccups.

Thanks guys