Powerfc/gtr Cold&warm Start Issues

[Penfold]

Just wondering if you guys could help with a few niggles with my current PowerFC setup.

Car - R33 GTR , HK GTSS Turbs, 700cc Injections, Tomei 260/260 Poncams - fairly late model PowerFC

Cold Start on PFC

- On a cold start it idles at 1700 RPM

- then settles down after it warms up a bit to idle at 1100 RPM

Hot Start after a short stop

- Idles at 900 RPM

Hot Start after waiting for 1-2 hrs (engine still warm)

- Hunts from 800 RPM to 1300 RPM or so

Any ideas?

SHould I have a play with the cold start settings on the PFC? Advice?

Cheers,

Thanks

[R31Nismoid]

Turn off the O2 sensors and then see if it still 'hunts'

If its no longer doing it, O2's are dead.

[paulr33]

when was the PFC installed? who installed it?

[Penfold]

Installed about 12 months ago by a pretty well known company in Brissy - they tuned it again later for 3 hours on the dyno after the setup got modified a bit.

I'll disable the O2 sensors & give it a try today.

when was the PFC installed? who installed it?

[paulr33]

when did the problem start?

what changed before the problem occured?

common problem solving tactics

[Penfold]

Always pretty much revved high since the last tune - what would be normal ? . The warmed up idle is fine and also when it is started when the engine is still hot. I could not even tell you when the warmish start hunting started because I normally just drive to & from work (only about 5 minutes) & for quick stops. There is not that many occassions where I would have the car really warmed up & then leave it for a an hour - thats when it hunts - it does settle down after a few minutes as it warms back up to the full operating temp.

Thanks

P.S. I do have datalogit & have the map downloaded so I could have a look at that.

Edited August 9, 2008 by Penfold

[paulr33]

well if you have datalogit then warm the engine up, get the water temp to near 80deg

save the tune, perform a data init and redo the self idle adjustement procedure

make sure the idle is stable (test it properly) once done and then load the tune back on

this should clear away any idle issues

before you ask, its in the PFC FAQ in my sig so read that on how to do the self idle adjustment correctly

if you dont do it or properly or skip parts of it you end up with a hunting idle

[Penfold]

well if you have datalogit then warm the engine up, get the water temp to near 80deg

save the tune, perform a data init and redo the self idle adjustement procedure

make sure the idle is stable (test it properly) once done and then load the tune back on

this should clear away any idle issues

before you ask, its in the PFC FAQ in my sig so read that on how to do the self idle adjustment correctly

if you dont do it or properly or skip parts of it you end up with a hunting idle

OK cool I will do that . Also when I checked under the Function Select:

Boost Control - Disabled

Ign/AirF Warning - Disabled

Knock Warning - Enabled

O2 F/B Control - Disabled => but I enabled it

O2 Sensor Reg - Disabled

Should I change any of them too?

[Penfold]

Ok,

I'm gonna do it - but wanted to check a couple of things.

Heres a copy of the map that was done by the tuner: Datalogit Map R33 GTR

Going by the date that was at the start of the year. However that map would have just been downloaded cold - not at operating temp

Will it yield a different map if it is downloaded before operating temp is reached.

Is there any settings that won't be in that map file that I should record as well? eg inj %, function settings?

Sorry for all the questions - just don't want to lose the tuned map.

Thanks again,

Pen

[heller44]

OK cool I will do that . Also when I checked under the Function Select:

Boost Control - Disabled

Ign/AirF Warning - Disabled

Knock Warning - Enabled

O2 F/B Control - Disabled => but I enabled it

O2 Sensor Reg - Disabled

Should I change any of them too?

02 f/b control I understand what that is, but what does o2 Sensor reg do?

Do you need it on or off for 32 or 33's?

I didn't see it in the paul's pfc manifest when I last looked either.

[paulr33]

02 f/b control I understand what that is, but what does o2 Sensor reg do?

Do you need it on or off for 32 or 33's?

I didn't see it in the paul's pfc manifest when I last looked either.

02 REG is needed for BNR32 owners

as the PFC unit for BNR32 and BCNR33 is the same unit but the BNR32 has titania 02 sensors and BCNR33 has normal 02 sensors.

the BNR32 needs to be set as registered to make them work as titania sensors properly. Otherwise with it off the PFC assumes they are BCNR33 style 02 sensors.

This is covered in the FAQ

apexi's official answer;

There is a difference in the O2 sensor for these vehicles. (With or without internal register)

After tuning, please check () "O2 SENSOR REGISTER" for BNR32, and NOT for BCNR33.

* It may be different if the O2 sensor is modified and/or changed.

[heller44]

Ok, thanks for the reply.

I only looked in the faq listed in your sig, thinking it might be easier and more relevant than swimming through 22 pages (and 437 posts) of thread.. which I didn't remember existed anyway..

[Penfold]

Sorry again,

But I came across another question.

In the Datalogit map it stores the Rev/Idle limits, function selects, injector settings ( 85,85,85,85.5, 86,86.6) as well the various water temp/air temp corrections.

So I thought I would need the injector seettings put in if I reinitialzed & did the reinitialize procedure - is there anythign else I should add. Also if I did it & copied the tuned .dat file back across it will overwrite all the data - so I should just keep the different temp correction stuff and overwrite everything else?

What I will do this mornign is hook it up & record a log file for the cold start procedure itself and a warmed up start & a warmish start - which settings should i make sure I log - or just all of them?.

Thanks,

Pen

[wolverine]

have you had a quick look at the various vacuum lines for leaks? they get old and split and perhaps the temperature change is making it leak more and then hunt.

[Penfold]

Not sure, can't find any leaks. I think it might be due to the temp correction or sensors.

Here's the logs:

http://members.iinet.net.au/~ptv/penfold/l...ntingatidle.dat

http://members.iinet.net.au/~ptv/penfold/l...ntingatidle.txt

http://members.iinet.net.au/~ptv/penfold/l...ldcoldstart.dat

http://members.iinet.net.au/~ptv/penfold/l...ldcoldstart.txt

I'll get up a really cold start where it goes up to 1800 RPM at idle.

Cheers,

Pen

[Penfold]

Ok,

Just to clarify a few things:

a) The map (.dat) file I downloaded at cold/warm/hot starts were all the same

b) The Self idle adjustment procedure does adjustments to settings that aren't found in datalogit (so copying data back on won't wipe the self-learn?)

c) I put the Injector settings, disable boost control in first after I initialize.

d) I leave the ingition/water temp correction settings as they are?

e) I do the initilizae at an absolute cold start?

Thanks again,

Pen

[sly32]

my mate had a few problems with the power fc and idling etc..., i then read in some imports mag or something that this is a common problem with power fc is the idle control on it isnt that good, and using different turbo's and cam etc can stuff up the idle, they suggested a hks idle stabilizer, i think they cost like $150 or something, and that way you can set up what voltage you want it to send etc. so if you car is only reading enough voltage to make it idle at 750-800 you can make sure that a voltage wont go below a certain amount so it will only drop to 1000, if that makes sense, anyways have a look at it on nengun or something, that might help you out,

JV

[Penfold]

Hmm,

Redid the initialize but now it seems to hunt more than before ( I did it from an absolute cold start & just added inj % & disabled BC ). It does have to be started from absolute cold start right ? Then I copied the tuned map back over the top.

Ok,I will redo the initilize procedure again tomorrow morning unless theres some other suggestions? then I'll copy the map it comes up with & post it up. Then I will copy the whole tuned map back over.

Any tips?

Cheers,

Pen

[paulr33]

the self idle learn procedure is covered in detail in the PFC FAQ

you should read this before wasting any more time

be sure to note

30 minutes must be set aside for it

the engine must be warm (80deg water temp)

you must not fiddle with the car (if you tap the throttle forget it, start over)

do the demister, aircon etc in the correct order and for duration

if you are unable to get a stable idle there are some additional things you may need to do based on your engine

if it doesnt idle properly you might need to adjust your AAC valve to let in more air to make it idle (ie : larger cams)

the apexi documentation states this

lastly - get a tuner to do it if you still cant sort it out

for %99.999999 of the time the out of the box idle works on almost any car, even cammed

[Penfold]

Awesome. The learning map at cold start explains why its all over the place now - i will correct tomorrow

Because I live in Bundy and nearest 4wd tuner is 4 hours way its hard to organize - its been tuned already but as I said initially - its the cold startin revving high & the warmish start hunting - probably did not get noticed in the initial tune

So checking what the usual corrections are to cold start to reduce idle & secondly for the warmish start to boost the idle RPM revs. Using datalogit there are a heap of correction tables but I was wondering what the usualy procedure is from someone who has modified these settings before.

Thanks heaps - its just a couple of bugs I was trying to iron out.

Also, I will eventually get it to tuner again - its just that the warmish & absolute cold start take days to duplicate on a regular basis to tune it out & I don't have the opportunity to leave the car in brissy for a number of days.

Edited August 29, 2008 by Penfold