P0505 with "super" MIVEC
 

Hey Guys,

I am using the MIVEC map that NJ has in the "How To Tune" thread.

Every now and again I am getting P0505 - Idle control or something! :(

Anyone know how to fix? reduce advance in MIVEC i spose?

Cheers
D

idle control system malfunction?

if its the same thing as my car (and a few few others), its because your idle control valve is clogged with carbon. you need to get it cleaned out

mines has doing it since about 10000 k's, long before any tuning :)

If the cleaning thing doesnt work you could lower the advance below 2000 RPM
If your idle speed has gone up then this will help that also.

I did not throw codes but did lower the cells below 2000 to stock values to fix idle issues

the car has only done 4000km's so i dont think its dirty... plus it doesn't do it on stock MIVEC!

ill try lowering the advance a little :)

Dave - how many steps do you have on idle stepper when you get the CEL p0505? I've seen this coming when for some reason the desired idle rpm was reached only when the steps to maintain the desired idle RPM were outside of the range (the base is set in one of the Desired ISCV Initial step). In order to get them match - you need to open/close the BISS screw. Then follow the learning procedure - warm up the engine, disconnect battery, connect, run on idle for cca 4-5 minutes until he idle goes through the learning cycle.

x2 that should fix it

ok i have reduced the MIVEC around the idle cell's lets see if that fixes it :)

How much is your ISC showing on idle when you get the CEL ?

55 steps normally, not sure at the moment of the CEL...

try to find in the evo9 service manual something like attached (from Evo 8 manual) - you are getting p0505 in case your steps are out of the range as stated there (of course assuming you have the stock values in the desired idle tables).

hrmm ok weird - I will log it when I get in the car but so far no CEL with the new MIVCE...

Well if all that was changed is Mivec and then 505 started showin up we can pretty safely assume Mivec map changes caused it. That said changing the values Should take care of the problem. If cam timing and base iginition timing are too far advanced that might make the ecu think idle stepper is out of range. (just a theory here)

Good Luck Tephra I think you got it m8 {thumbup}

well after warming up my car is running 27 steps.. and still no CEL... so guess its mivec related :)

Just to clarify - the super MIVEC caused that in order to maintain the desired idle RPM - the ECU opened the stepper (to 55 steps). As this value is not standard (stock) - the service manual describes some scenarios/conditions which if not fulfilled within certain period - will give this malfunction (CEL).

So yes - changing MIVEC resulted in decreased ISC steps to maintain the desired idle RPM - and now you should not get CEL (as you are close to what I think is the range for Evo9. In case you still get CEL and do not want to change MIVEC further - then you just need to open the BISS screw cca half a turn and reset ECU and go throught the idle learning procedure (cca 5 minutes of running a warm engine on idle).

ok piccy of the BISS screw? just for future reference!

thanks by the way :)

BISS (basic idle setup screw) or SAS (speed adjust screw) is located on the upper part of the throtle body - picture (from manual) is attached.

i was having the same idle code when i first used his tune. I just changes the Idle areas of the Mivec table back to stock. Then the problem went away, and i was back to ilding like normal

its back...

obviously increasing MIVEC causes it to occur, but my old car had no problems with that MIVEC map..

so i'm going to play with the BISS screw this weekend :)

ps my ISCSteps was 50 after a long drive this morning...

There is no reason to have advanced Mivec at idle. Why would you do this other then to get a lumpier idle?

I've had a ton of IX's through the shop and every single one I set to have no Mivec advance at idle and never throws this code.

my mivec table attached.

in answer to your question, I think its good to have a little MIVEC advance so that when you start advancing in high load/rpm the MIVEC cams are already halfway there...

i thought the cams had a slight delay (ie not instant)...

Try this and see if it helps:

http://www.norcalmotorsports.org/use...efty_mivec.gif

Also, what is your idle set at?

stock...

right so i put my MIVEC back in - why? because I almost stalled off the line in traffic...

as far as I am concerned we need some mivec in these areas because it helps torque or whatever.

so i screwed my BISS in 1 full turn and my ISCsteps is no about 36... I didn't need to reset the ecu just went for a drive and it worked it out :)

lets hope I dont get the CEL nemore :)

Its wierd that you're getting this CEL. In all the fiddling I've done with MIVEC, I've never had a P0505 CEL. I think that's the case for most other people as well.

i think maybe my BISS was out of adjustment from the factory... just not enough to trigger the CEL for a stock tune..

I got this code for the first time tonight on an 05 VIII with stock cams and the ver 96530006 ROM swap (for the map switching ability). Fuel trims are fine, and I've tried higher and lower (stock) idle values with no success. I left the car running 8* of timing at idle because we simply ran out of time -- not sure if that'll help or not. I'm hoping that it's ignition related because he's running on plugs that have 40,000 miles on them and was getting ignition-like breakup at 26psi during the race gas tune.

Any other ideas if plugs and extra timing don't work?

ISC values are stock, as are the idle values at the moment.

what ISCSteps are you logging at idle?

I got that same code when I used a 96530006 on a 05.

I still have to swap my 05 over to this rom to see if I get the same code.

Could be an issue?

I do know the idle and ISC maps are different in the 96530006 compared to the 05 rom. I tried swapping the 05 idle/ISC values over with no luck.

Dave,

Instead of advancing mivec why not add more (1-2*) of timing at those load levels?

I have added more timing low down and find response to be alot better, but I do have HKS 272 cams.

SK

Humm... Im having this same issue on my 05. my plugs are 2k miles new. map switching E85 and 91. I would like to find a resolution to this soon.

So three confirmed issues of this with 05's.

I am starting to wonder if there was a hardware change on the 05 mid year or something.

mine is fixed... adjusted BISSS. problem went away. idle was at 900-925... bumped to 1000 no prob.. i dont think my problem was the same as all of yours.... unless it comes back.

Getting the 505 code on the 96530006 ROM, as well. I had advanced my timing in the idle cells so will drop them to see if that helps. Been running without the CEL for about 2 weeks and it just started so I will let everyone know if it comes back tomorrow.

Guys - the fix for this:

get evoscan 2.5
warm up car
hit the "SAS Activate" actuator in evoscan
dial in 850 idle with BISS Screw
hit the "SAS Clear" button

should be good to go!

Does this set your idle at 850 or just reset the system? Will this work on the 8's?

Adjusting the BISS sets the base idle, once set the IACV takes over to fine tune and keep the idle correct.

It should work on the 8's...

Easy way to tell if your BISS needs adjusting is to warm up the car and flick the "SAS Mode" Activate button, if your idle drops below 800rpm you need to adjust the BISS...

Setting up BISS screw correctly fixes the p0505 on evo8 - done 2 96530006 already.

Without actuator functionality it was a little bit more difficult - but still possible - you just need to achieve the 850-900 rom while having the idle steps below 10 (warmed up engine, no AC, no other load on the engine). And at the end do the idle learning procedure (disconnect battery, reconnect and the start and let idle for 7-10 minutes) That;s it.

With SAS actuator, Warm-up engine, Activate SAS, play with BISS until you have RPM there wehre you want (should not be too far from the basic idle values that you have in your idle tables) ; cancel SAS and you are done.

Ok, so I had the P0505 error on my Evo8, ROM ID 96530006.

I followed the above instructions, when I avtivated SAS, my RPM dropped to under 600 rpm. I adjusted the BISS screw until I got it to just over 850rpm.
It seems to have fixed the problem with P0505, but now the car is idling at 1120rpm when in neutral.

I have turned my "Desired Idle RPM-Neutral" values down but that made no difference at all.

Where else in the ROM tables can I adjust to get my idle down to 850ish rpm?

Thx.

your ECU has learned the wrong idle speed, u need to battery reset it :)

or flash a new rom to it...

I have done both of those....

Very recently I flashed my car with the new ROM that came with the 5.10 patch, - I copied my tables over and updated the relevant def file for my ROM-

Then last night I did the SAS/BISS adjustment followed by disconnecting the battery for roughly 30 minutes.

Not sure if this has any bearing, but while idling at 1120rpm my ISC Steps are sitting at 40.

Had the same pb on a Evo 8 with 96530006 ROM...

Done the SAS/BISS adjustment thing...and had a 1,400rpm idle...dumped another map...same thing...reset the ECU by removing fuse...and {thumbup} a nice CEL free 900rpm idle!! (fitted S1 cams, hence I had to raise the idle)

Thx for tip! :thumbup:

edit: just realized this is a "mivec" thread... oops

Had to revive this 1... :rolleyes:

So had an evo viii on the dyno today and popped the P0505 (96530706 rom) upon start up, and comes back right away, after clearing it...
Heres all of the idle tables. Running Kelford 272's...
I Put it into SAS mode and idle didnt budge.
Is this a rom issue? Im pretty sure the car was converted to the 9653, but dont know from which rom... :updown:

Any help would be appreciated!

No I didnt log ISC steps, because cell didnt pop up till after we were done tuning. Started the car again, to park it, waiting for my buddy to pick it up, and popped up. Read it, cleared it. Started the car again, and came back...

Not sure if this helps much but I just got lazy and turned it off on my personal 05 running 9653. I started getting it when I moved to 9653. Not all the time but if it would trigger it would always be right at cranking startup.

Again, I just got lazy and turned it off in the bits.

Thanks for chiming in. {thumbup} Can u enlighten me on the correct periphery bit to disable, or even better how to prevent it! The only thing I could find going thru the periphery bits (I did try to disable)
was FCA Bit .8 "P0506, P0507 Idle test" I disabled it, flashed it, cell didnt go away... :confused: Tried to read it, could NOT, tried to clear it, could NOT... Changed the bit back on, flashed, and was able to read/clear it... :updown:

So you can delete the p0505 from an 05 evo 8 by clearing the bit?