hunting idle / poor throttle response

[krasyvy]

few questions after my swap has been complete and almost running.

Hunting idle. My breeze cluster has not tacho but my idle is really really up and down. There are a few things I read that it could be

1. TB Gasket - Need to be replaced
2. IM Gasket - is fine
3. Ex. Man. Gasket - needs replacing
4. Adjust Idle - How do I adjust my idle? I know where the screw is but which way do i turn it and by how much?
5. Timing?? - WIll check with timing light
6. Clean throttle body
7. TB sensors - these are fine AFAIK.

ANyone have any further ideas as to why the idle is hunting like crazy? and really loudly..


Also. I find that my throttle response is terrible, to a point where my car stalls. At the moment it isn't drivable because of this but the idel would fluctuate so much that at times the car will have enough strength to go up and down my driveway hill and other times it wont make it and will stall.


Why is my throttle response shithouse????

Any ideas would be heaps helpful.

I will try a few of the things mentioned and get back with the results.

[krasyvy]

Fyi:

Engine Is D15b Vtec

Conversion Was Carb To Efi

Ecu Is P28

[ECU-MAN]

is the MAP in your ECU ment for your engine ?????

does the ecu match the Engine

[krasyvy]

yes, the p28 or p08 can be used on my engine

any ideas?

[VT3C]

man i used a P28 to run my B16A for a while - that wouldnt cause your problems.

is your B16A a JDM item ? if so it's looking for an ELD.. this can effect the idle..
alos your IACV's screen may be blocked - remove, clean and replace screen/gasket.

yout throttle response COULD be you timing, but if it's stalling when you stomp on it, then i'd say your TPS (Throttle Position Sensor) is not set correctly or is faulty.

take it off and when you re-install make sure the little tab goes inside the saddle for it.. if still hunts, check it's voltage etc.

[Weq]

tps and fitv is fine - came off a personal engine.

TB gasket leaks will cause hunting because unmeetered air is getting in.
other cause is IACV or a faultly injector (check plugs maybe?)

edit;
also timing.. try switching the dizzy back and forth while the engine is on and see if it makes a difference..

[krasyvy]

thanks weq and vt3c

spark plugs are fine

i tried moving dizzy back and forth and no luck with that

the stalling occurs when i try to go up my hilly driveway - on flat it's ok...but i've only test driven on my driveway.


so timing could be off eh?

ok i will try that next and see how i go..

will also get a throttle body gasket and clean my TB and see how that goes.

if anyone has any other ideas i'd really appreciate the help.


would the stalling be only due to the timing?

[ECU-MAN]

yes, the p28 or p08 can be used on my engine

any ideas?
you realy didnt answer my question

What Im trying to ask is

is the fuel and ignition MAPs in the ROM of your ECU ment for a D15 engine that your making it run. if its not and the ecu is ment for a B16a you will have these sort of problems. especially hunting idle.

what engine did your ecu prevously run

[krasyvy]

p08 is meant for the d15b

p28 is pretty much identical and can be used without problems on the d15b

as i've been told and read about on OH and d-series.org

[ProECU]

krasyvy

the ECU program is more than likely your problem. The P28 is for a D16.
Hunting idle is a symptom that you are runnin rich.

Install a program that is meant for the D15,
If you cant do it, I could do it for you.

[krasyvy]

so the p28 ecu is causing me to run rich?

i was told that it will run fine on my engine

or u want me to pay for something i dont need?

;) ;)

[ProECU]

ok man, be that way.

good luck sorting it out.

[krasyvy]

i knew you would over-react.

;) = wink = joke.

your advice would be appreciated, just the ecu guys (including you) get a bad rap for advertising their services willy-nilly.

it was just a joke.

[ProECU]

like I said, install the right program and go from there.
I wasnt advertising I said I "could" help if you couldnt do it yourself....

perhaps I should retract that offer alltogether

[krasyvy]

ok so using the p28 would cause me to run rich / idle fluctuations??

ok i'll look into it thanks.

[krasyvy]

pro-ecu - can you provide just the p08 chip?

[ProECU]

yeah...I "could"

[krasyvy]

thanks to proecu and my stupidity it finally threw a CEL at me

cel 20,21 and 8

8 is the only thing of concern to me at the moment becoz it is TDC Sensor.

Would this be the cause of my poor throttle response / stalling / hunting idle?

How do i fix the TDC sensor?

dont tell me new dizzy.

[bennjamin]

it coudl be the dizzy. Would explain the poor throttle / stalling.
Take the thing apart and look for urself or replace what u can

[krasyvy]

Whats the TDC sensor's purpose?

to detect top dead centre and hence to ensure correct ignition timing?

if thats correct and the dizzy is f*cked then that would put my timing off.



i dunno...if someone knows then please, educate me

[krasyvy]

any ideas?

[ProECU]

yeah, catch me online when I get home tonight.

[LVNIT]

Personal experience with idle hunting was the car running too rich on idle. This was with a P28 running my B16A2, leaned out the idle, fixed the problem..

[ProECU]

there's a lot more going on in this case than has been explained....

[LVNIT]

I hope your not just using a P28 with the stock rom to run the engine either. Shiit is going to be all over the place :)

[krasyvy]

well i thought i could use the p28 in place of the p08 but i cant so now i'm after a p08

[krasyvy]

there's a lot more going on in this case than has been explained....

there is?

[bennjamin]

did you plug up/short out the 10+ pin connector on the RHS of the loom ? (3 plugs , one goes to dizzy , other goes to front headlight etc , other is uncconected)

[ECU-MAN]

I hope your not just using a P28 with the stock rom to run the engine either. Shiit is going to be all over the place :)

he is,

this is what I was trying to explain :cool:

[krasyvy]

yeah I am - I read that the p28 shouldn't cause problems

http://www.d-series.org/forums/showthread.php?t=30063

but I dont really know how good their advice is; wether it's experience or speculation or whatever. And a few of the p28's were chipped so.


Anyways, with regards to the ecu - can i get it repaired or should i just purchase another one?

[krasyvy]

did you plug up/short out the 10+ pin connector on the RHS of the loom ? (3 plugs , one goes to dizzy , other goes to front headlight etc , other is uncconected)

RHS?

do you mean short out the 10 pin connector on the drivers side of the engine bay?

What does that affect?

And yes, that has been done.

Might call hanny's tomorrow, see what they can do about my dizzy.

[krasyvy]

OK just to update. After checking the ECU codes...14(IACV) and 8(TDC sensor)

Went down to Hannys to get dizzy checked out.

Robert told me the dizzy looked fine-the bearing inside dizzy would be rooted if the dizzy TDC sensor was to be playing up. But he said I should test my car with another dizzy.

He told me try the FIT and IACV valve and even lent me a IACV valve to try

I cleaned TB put in new IACV and FIT valve and adjusted internal piston in FIt valve (to Hannys advice).

Still the car Idle is jumpy/hunting?!:thumbdwn:

If its not TPS, IACV, FIT valvle then where to next?

Could teh ECU be giving me the wrong codes cos its P28?

[Weq]

OK just to update. After checking the ECU codes...14(IACV) and 8(TDC sensor)

Went down to Hannys to get dizzy checked out.

Robert told me the dizzy looked fine-the bearing inside dizzy would be rooted if the dizzy TDC sensor was to be playing up. But he said I should test my car with another dizzy.

He told me try the FIT and IACV valve and even lent me a IACV valve to try

I cleaned TB put in new IACV and FIT valve and adjusted internal piston in FIt valve (to Hannys advice).

Still the car Idle is jumpy/hunting?!:thumbdwn:

If its not TPS, IACV, FIT valvle then where to next?

Could teh ECU be giving me the wrong codes cos its P28?

i adjusted the fitv before i gave it too u.

if the ecu is throwing those codes, it means it cant find or has problems with those sensors.. a p28 should run a d15bvtec IMO. u really need a way to measure the mixures and make sure everything is in check - because wrong fuel maps can cause bad idle and everything else.

[EuroDude]

The FITV knob was screwed all the way in yeah?

[krasyvy]

i adjusted the fitv before i gave it too u.

To clear up Fitv was fine no probs. It is not the prob
adjusted just to be sure as a check

[ECU-MAN]

recheck your wiring for the TDC and EACV

if you have TDC problems as mentioned to you before, your car will run like crap. the ROM in you ecu isnt doing you any favours, but you still should be able to rev it so check out your TDC.

[krasyvy]

i adjusted the fitv before i gave it too u.

if the ecu is throwing those codes, it means it cant find or has problems with those sensors.. a p28 should run a d15bvtec IMO. u really need a way to measure the mixures and make sure everything is in check - because wrong fuel maps can cause bad idle and everything else.

the only reason i think that the ecu is throwing me all messed up codes is because i tested the wiring to the iacv.

what i did was got an IACV that i knew worked fine..

its got 2 wires coming out of the connector plug - 1 wire received 12v (black and yellow) and i tested this with a test light.

the other wire i wasn't sure if it was connect to A9 on the ecu properly. So I connected a new wire to the blue and yellow wire on the IACV plug and ran it DIRECTLY to the ecu pin A9.

Still gave me code 14.


Can anyone explain to me why?

[krasyvy]

would supplying 12v to the blue/yellow pin on the iacv also supply 12v to the black/yellow pin?

because this is whats happening for me at the moment.

[krasyvy]

BUMPO.


I've wired the blue/yellow wire directly to A9 on the ECU and the black.yellow wire directly to IG2 so i know the wiring it PERFECT for the IACV.

It stills gives me code 14.

Can someone please explain why?

[krasyvy]

another thing about the hunting idle is that it ONLY occurs when the engine warms up.

it will rev and idle fine when cold but after running for a little while it will start hunting.

[iamhappy46]

I reckon fix the TDC sensor in the dizzy first. Mainly because it controls the ECU reference point for RPM.

Have you checked the expected ECU voltages that I posted a few weeks ago??

The P28 ECU is for the D16Z6 and is fully capable of running the D15B VTEC from idle to VTEC switch point. The fuel maps only majorly differ from VTEC switch to redline.

All State Autos in Queensland should have a Honda P08 ECU in stock, not sure on prices but call them on 1800 505 517

[krasyvy]

the voltages were fine and didn't cause a problem.


any ideas on what i've done with the iacv?

[ECU-MAN]

what is the resistance of the EACV disconected