[Mk2] [Turbo] Fitted my power fc,and have a puzzling result.

[planted1]

Hey all,

After checking E1 and TE1 with my rev 3 ecu fitted,
and finding no fault codes,i fitted the power fc.

This is a rev 3 loom all the way from the passenger footwell and including the engine loom.

What happens is ,on starting it idles lumpy,but that could be the hks 264 cams,
when i blip the throttle and allow it to return,
it hunts up and down by about 4 to 5 hundred revs,over and over again.
Also the car is burning terribly rich.

The power fc is running on Apexi base map,
tvsv has been replaced with an apexi boost solenoid,
AIT sensor located in airbox,
mat sensor is located beneath the throttle body,
iscv was removed ,cleaned and refitted.

blowed if i know why it hunts or runs so incredibly rich,
anyone had any experience of similar results

thanks
steve

[simpson_eh]

surely if it running the standard base map the cams will throw it out anyway hence the lumpy idle it thinks it has standard cams

[planted1]

What i did to test that was to put back in the rev 3 ecu,
it stopped hunting straight away,
good thinking though.

[Kongaroo]

Surely it's just the PFC self-learning the idle? This is actually one of the cooler features of the PFC in my opinion.

You leave it to idle (hunting) for about 10 mins or so with the electrics off. Then about 10mins with the electrics on (it will start to hunt again). Then about 10mins with the aircon on - it will hunt again and then settle once the idle has been learned.

Hope that helps

[simpson_eh]

lol i forgot all about the learning mode lmao i did it not long ago aswell

[planted1]

ive taken a small video which i'll upload later so you can see what i mean.

Does it self learn every time you switch ignition on
or is it a one off thing?.

Ive also noticed that in settings vta2 is at a constant 4.99 this never changes,the other sensor feedback voltages change slightly when revving
does vta2 stay constant?
Its to do with secondary idle i think.

cheers
steve

[Kongaroo]

ive taken a small video which i'll upload later so you can see what i mean.

Does it self learn every time you switch ignition on
or is it a one off thing?.

Ive also noticed that in settings vta2 is at a constant 4.99 this never changes,the other sensor feedback voltages change slightly when revving
does vta2 stay constant?
Its to do with secondary idle i think.

cheers
steve

It will continue to try and learn idle each time you switch on until it reaches a stable setting (ie. when the rev hunting stops).

If you want to restart the idle learning process from scratch just choose the initialise powerfc function which brings the map back to the default base map and restarts the idle self learn process.

It is possible to let the ECU self learn for eg. just the electrics off idle settings and then learn the idle for electrics on or aircon on at a later date. You will know if the self learn is incomplete if the ECU begins to hunt up and down the revs.

VTA2 doesn't seem to change on my car either although mine is constantly at almost 0 as opposed to yours which is almost constant 5v. I believe this sensor is for the secondary throttle body which you will only have if you have a car that came with the stock traction control system (like mine did but I had the TRC throttle plate removed).

I wouldn't worry about the VTA2 value. All you want to check really on the sensor section is whether any sensors are high lighted which show it is reading out of spec.

VTA1 is the main throttle position sensor voltage so yes this will increase as you push the accelerator pedal to the floor. My own car idles at about 0.31v.

Remember the default basemap is for 540cc injectors - if you have larger injectors you need to adjust the injector percentage value or the ECU will struggle to achieve a good idle.

[planted1]

Thanks for taking time to explain

The injectors are 540 at the moment so should be ok
aircon has been removed as it was retro fitted by the previous owner
this being a uk na model.
I'll ignore vta2 then,as the throttle body was off an st205 celica.

Just seems to be taking a real long time to self learn,
and using a lot of fuel to do it ,half a tank since yesterday afternoon.

Heres a small vid,ignore the paintwork state as its yet to be sprayed.
Thanks again
steve
http://s197.photobucket.com/albums/aa18 ... AG0002.mp4

[Kongaroo]

No worries Steve, hope you get it sorted.

It was a little hard to tell from the video but it seemed like your idle with electrics off became stable and then the hunting process started again once you turned on the electrics? (it's hard to tell from the video what RPM the engine settled at prior to you turning on the lights but it looked a little high?)

It should take about 10 minutes of idling with the electrics/lights off to get the idle to start to become stable - by this I mean the range of rev hunting should get smaller and smaller until it no longer hunts.

Then when you turn the lights and fans on the larger hunting range should start again and take about another 10 minutes or so to begin to become stable.

If you are not noticing the rev hunting range get progressively smaller and smaller even after say 10 to 15 minutes idling then there are couple of things to double check.

Did you adjust your base timing at some point and are you sure it is correct?

If you changed your cambelt recently are you a tooth out of position?

If the timing and cambelt are correct then the only other thing that may help is setting the idle values slightly higher - say 100 rpm higher for electrics off idle and also electrics on idle values and then leave it to self learn again.

[jimGTS]

leak maybe?

mine hunted up and down like crazy when one of the fuel rail orings fell off when i was installing the fuel rail, basically like a big boost leak.


powerFC setup really doesnt take very long, and should settle pretty quickly from my expereience on my own cars.

[planted1]

Hi again,
I'm pretty sure the hks cams were set correctly,
103 exhaust btdc
110 inlet atdc
after that the cams were degreed
all carried out by the engine builder,as it was beyond me,
yep it does seem to be idling high though.

If i put the rev 3 ecu back on it doesnt hunt at all,
it does idle high though,maybe 1500.

With the rev 3 ecu ,when i fired it up for the first time a couple of weeks ago,it was very lumpy and would cut out ,so i had to hold the revs higher untill warm,then loose the throttle and it would be stable yet high.

The distributor is as far over to the left as possible,just wandering whether the problem may lie here?,
or throttle stop adjustment screw(as it was bought from ebay)

Basically it idles high with either rev 3 ecu or power fc fitted,
with power fc fitted it seems to be a lot richer than with the rev3 ecu.

I'll try the pfc learning procedure again and see what happens

Jim,
i cant seem to see or hear a boost leak,but,i will check,just in case.

thanks guys
steve

[Kongaroo]

I have a feeling that your cambelt may have shifted and could be a tooth out as this can happen even with experienced mechanics. Luckily I can just leave this to Peter at SBITS to get done being the MR2 guru that he is

BTW I had a similar problem getting the car to idle following my most recent build. It would only idle when warmed up (would keep stalling) and the powerfc was unable to learn the idle.

When Peter double checked the cambelt it had shifted during the final stage of placement and was a tooth off. Once corrected it worked fine. Obviously no idea if this is your problem or not but your car symptoms are similar to mine so might be worth at least checking this is not the problem assuming the 2nd attempt at ECU idle learning fails.

[planted1]

Hi
Its something i hadnt thought about but i will check it as it does make sense,
jimgts has probably forgotten that he had a very similar problem back in 2009
hks exhaust cam a tooth out,and a fried power fc

Ah well i'll be taking off the cam gear cover and checking on saturday hopefully
Thanks again for your help
steve

[planted2]

Hi all,
Finally after two days i found the problem.

Changed the distributor in case g1 pickup had failed,no difference.
changed the iscv,no difference.
Changed the ait sensor,no difference.
metered out the o2 sensor,and it was within its range.
changed water temp sensor,no difference.
Ran the pfc through its learning process,three times,allways failed right at the end.
Reset the plugs,cleaned the dizzy cap and changed the rotor arm.
Disconnected the hand commander,no difference.
removed cam cover and checked cam timing,all marks aligned spot on.
lowered vta1 from 65 to 35 ish
checked for vacuum leaks with a smoke test,re-tightened all clamps,
checked all hoses,clips and connections.

I had been looking at how i had the apexi solenoid valve connected up,
my wastegate only has one connection.
i had com port to actuator and no port to turbo housing,
and therein lay the problem.
i now have com to actuator which is teed to compressor housing,
and no port to intercooler piping,which i hope is right.
i started it up and it sounded much better,held idle,all though its a little lumpy,which i put down to the cams,it revs fine and returns to idle as it should.
idle seems a little low around 800 give or take 25
Just happy that it seems to be ok
cheers
steve

[djpkins]

My AVCR is...turbo housing to boost control solenoid...then, boost control solenoid to actuator...which as you say should have one port blocked off...as should the vac line that went to the blocked actuator port.

[planted2]

I agree with you,
thats how logically you would think it should be fitted,
inbetween the actuator and the compressor housing,
just doesnt seem to want to run properly that way
and its strange that it runs great the way its plumbed now,
solenoid com port to actuator,with a tee to compressor housing,
and no line to intercooler hard pipe,
shout up guys if this is dangerously wrong
thanks
steve

[planted2]

ok,
ive now put it back the way it should be,
silly me

steve