B18C R w/Individual throttles - suddenly will not idle!

Hey guys,

Car: 1992 Civic Breeze w/ B18C R + ITBs + Power FC

At the moment when I go to crank up the car it will start then die out immediately. So i have to crank it with a little bit of pressure on the accelerator. Then if I take my foot off the accelerator it will settle to about 1000rpm briefly, then drop lower till it shuts down. When driving at the moment and approaching lights i slow down, put it in neutral, hold throttle lightly above 1000rpm and slow down to a halt with left foot on brake pedal. It allows me to run the car but its somewhat annoying...

I did start it up in the afternoon and for a little while there i gave it a big blip and it stabilized the revs... but then again any time after that I've had to artificially hold the idle.

I will be taking the car to my tuner as soon as i can get around to it, but that will be sometime late next week at best.

Any thoughts and suggestions are welcome.

regards
Shiraz

throttle cables might need adjusting..
or injectors malfuntioning, or its connectors arent pluggd in correctly or came loose.

had a car come in to my work with the same symptoms youre sayin. (not a honda though, and didnt have 4 TB's lol) and it had a injector connector loose, the pin fell out, n startin misfiring a cylinder, and had a smooth stall if your idling.

buh might be different with your setup, just my input :D

this the white EG that was forsale?

Is there a box covering the itb's?

Check to see that the sensor thats connected to this hasnt come loose.

this happened to my mate's parents car,
he fixed it by adjusting the piping leading to the throttlebodies. (something along those lines)

I can ask him again if you havnt fixed it yet.
Let me know

Could be many things from throttle position at idle, amount of fuel at idle/timing, map and or t/p sensors, temp compensation and decel settings, nothing im sure a decent tuner cant sort out given a few hours.

what Slaz said +1!

the idle issue will be the throttle position at idle as stated by slaz. You need to adjust it just right, took me hours to do, but it's just a little screw that keeps your TB just a tiny bit open.

This is because when using ITB's there's no IACV.

Thanks guys. Car will be going to tuner soon, but thats a few days away at least. Today the car started out as i mentioned, i had to drive around carefully, when approaching traffic lights i put it into neutral, lightly touched the accelerator (very gently) which made the car idle nicely, and left foot braked...

Thing is randomly (i am thankful that it happens at least!) if the car starts well the first time then it is able to hold a good idle speed, and at the moment its doing that so i can drive it around normally. the intermittent nature of the situation is a little confusing, you'd think if the butterfly position at idle is a problem (i.e. fully closed) then it would be a consistent problem until resolved?

Oh also guys, when the problem of engine dying out occurs, if i pump the brake pedal continuously then the revs rise and it will idle... only while pumping the brake pedal. I'm sure its related to a vacuum issue somehow, just no idea what i can do about it myself if anything...

From what you have said it sounds tuning related. Everything we could suggest is just a guess. Until then try adjusting the idle up a bit.

Ok well some more feedback, car was great all night, in fact ran without a hitch. Idled well at every stop. Until one point were I gave it a little bit of a push, and heel toed down shifting. Then it started idling from that point about half normal, which felt like it was ABOUT to die but it didnt. Its as if its related to the brake system somehow? I'm hoping that Vin at docklands Subaru can sort it out. Any suggestions as to which shop is knowledgeable with modified hondas like mine in Melbourne? Thanks for your input so far guys I appreciate it

Go see Andy at AKmotorworks.

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Originally Posted by grumpy rooster

Go see Andy at AKmotorworks.

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why do you recommend him?
is he hooking you up as a neptune dealer or something?
(why am i even protecting the monkeys)

Because he has experience with ITB setups on Hondas.

Who do you recommend? Give the guy some advice. :)

who previously tuned the car? Give them a call and tell them whats going on.

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Originally Posted by grumpy rooster

Who do you recommend? Give the guy some advice. :)

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i wish i knew of a honda tuner in australia with a good rep.. (i personally think honda tuners have some weird eliteness ego that is continuely conditioned by the noobs they deal with, so they then feel they can be a bit dodgey because the noobs dont have the knowledge to question)


i would be questioning what variable is impacting the idle.. seems weird for one night it runs fine and then the next day it goes to shit..
doesnt sound tune related does it?
sounds more like a vacuum leak or sensor issue?

if its related to brakes then u have a vacuum problem. possibly leaking brake fluid into the brake booster and take up vacuum space.
this happend to m prelude. everytime i hit the brakes the car would stall. wen i disconnected the vacuum line to the booster and sealed it off the car never stalled but i had no brake assist(hard pedal). so i drained the booster and the car drove a beaut until it started stalling again to which i got rid of it :)

jus my 2c

brakes.....WTF????

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Originally Posted by 10KRPM

brakes.....WTF????

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Well that's right, WTF... weird problem, maybe has a weirder solution!!

brakes = brake booster
brake booster uses vacuum therefore if u have a failing(leaking) booster u have a vacuum leak and that causes the car to STALL

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Originally Posted by bfeboi

brakes = brake booster
brake booster uses vacuum therefore if u have a failing(leaking) booster u have a vacuum leak and that causes the car to STALL

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That's what I would have thought. Not sure how it explains the intermittent nature of the problem?

Again today the car was unable to idle at all. Can anyone advise me as to what hoses I can check/disconnect to try and locate the problem?

Please identify in engine bay pic (car run with socks on atm):

http://img386.imageshack.us/img386/479/img060719ja5.jpg

how about getting in touch with charles and the blokes who put the car together.

maybe he experienced it before?

UPDATE!
I just went outside and disconnected the brake booster vacuum line (i took a random guess). Started it up and it idled! Idling was around 800rpm. I took it for a spin, obviously very firm brake pedal however it idled fine, no stalling anywhere. As soon as I tried to connect the vacuum line up again the engine almost stalled. Anyone know what this may suggest?

Quote:

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Originally Posted by bfeboi

brakes = brake booster
brake booster uses vacuum therefore if u have a failing(leaking) booster u have a vacuum leak and that causes the car to STALL

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So how do you fix it then? Sure you can drive around without the assistance of a booster, but what's a solution to this?

change brake booster.

Thing I don't get it, brakes are working awesomely well... I mean hit the pedal and your face is likely to fall off! So how is the brake booster not working?

Your ITB's look to be old OER units.
It's likely all of your issues stem from the dodgey linkage system that comes with these throttles.

What is it exactly that makes the linkage system dodgy? So far people I've spoken to have identified the problem as being with the brake booster or PCV valve. I'm not sure how you linked the problem to the linkage system?

Well we had a set of OER quads on a ITR motor. The linakges broke.

That's fine, but it doesn't explain how that's related to my current issue? Thanks for the heads up though.

Have you tried bumpng up the idle to see if it makes any difference? I'll guess that it will now idle. Did the idle rpm change when you disconnected the brake booster? Did it happen to go up?

If you need a Tune, RevZone at Nudawading work frequently with Hondas.

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Originally Posted by grumpy rooster

Have you tried bumpng up the idle to see if it makes any difference? I'll guess that it will now idle. Did the idle rpm change when you disconnected the brake booster? Did it happen to go up?

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The car actually will not idle unless the brake booster is disconnected. With it connected it will not idle.

What I am getting at is if you increase the idle speed will the car idle with the booster hooked up? In other words will the car not idle regardless of idle speed or does it just not idle at the idle speed it is at the moment?

Well I tried to increase the idle speed using the powerFC hand controller, but it hasn't made a difference. At the moment I set the idle speed to about 1100 or something, but its idling at around 800... Changing the idle speed on the powerFC didn't affect the idling at all.

Also another thing is at the moment the car will not crank over unless I have a my foot on the throttle. Strange...

Sounds like a throttle cable problem..
Maybe got too much slack on it?

Try adjusting the throttle stop screw on the throttle bodies. It will be the screw that has like a spring on the back of it that rests against the linkage to stop it going too far closed. Screw it in a bit more. This should physically hold the throttles open more and keep the car running if you adjust it far enough.

BTW, the more you talk about these problems the more it is tuning related or some physical problem with injectors or fuelling.

should take your car to someone who knows what they are doing. you seem a bit lost when it comes basics.

As for the idle thing with the brake booster disconnected, are you blocking off the line or just leaving it exposed? Cause if you're just leaving it exposed, it can idle cause it's getting air from that line.

From the picture you posted, your ITB's are using a Vacuum box setup with the IACV connect to it. Is the IACV even wired up? From personal experience, ITB's and vacuum boxes don't work well together, it makes the map sensor readings laggy and weak.

I didn't say I was a tuner :) I usually just...drive.
I wanted to post the symptoms on here to get feedback to try and pinpoint whether its hardware related, tuning related or whatever. I did mention I will be taking the car to a tuner, however because I can't get there this week I wanted to try and shortlist the problems. Which is what this forum is about anyway :) I don't mind fiddling with basic things, I'm new to NA cars and I guess ITBs are a bit different, I'll leave adjustment of those to the tuner. Thanks for the input so far.

Also barefootbonzai is it possible to run without the use of the vacuum box?

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Originally Posted by STiR

Also barefootbonzai is it possible to run without the use of the vacuum box?

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not possible to run without vacuum box . You need vacuum to be there.
try to raised the idle on your throttle body first and see how it goes .

you can yo. just T off the lines to brake booster and map sensor. but then that will eliminate the IACV.

but yeah, as myself and many guys on here have stated. adjust the throttle body position.

OK guys I'll have a look under that bonnet this afternoon and see what I can do about adjusting the throttle position a little, we'll see how it goes.

Just remember, adjusting the throttle opening to make it idle higher is only a stop gap fix until you can get someone to look at it. Its by no means going to fix your problem. You need someone to go over your setup and tune and work out what it wrong. Until you do that there really isn't much more help anyone can give you.

For sure. Fiddling here and there will only help me to get to know the systems a little better, but undoubtedly I'll be heading out to my tuner as soon as possible.

Quote:

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Originally Posted by STiR

Well I tried to increase the idle speed using the powerFC hand controller, but it hasn't made a difference. At the moment I set the idle speed to about 1100 or something, but its idling at around 800... Changing the idle speed on the powerFC didn't affect the idling at all.

Also another thing is at the moment the car will not crank over unless I have a my foot on the throttle. Strange...

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not enough air to start the car?

Didnt you test drive the car before buying it?

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Originally Posted by 10KRPM

Didnt you test drive the car before buying it?

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What's that got to do with the price of fish? Car was driving fine, then couple days later found a few hiccups. Such is the world of modified cars.

With some online guidance from Yonas I went out and adjusted the throttle position at idle. It was a lot easier than I thought, I was just afraid of breaking something...

Brake booster now hooked up again, idles nicely around 1100-1200 rpm and starts straight away. So until I can get it to a tuner hopefully it should behave itself!

price of fish? bad analogy but your point did get through.....barely.

Well im glad the car is running, now all you need is a fresh tune and prepare for NA powa!

You haven't heard that one before? It's quite old... much older than me I'm sure! Vin the master tuner of power FCs will be getting his hands on the car soon and from the way the car goes at the moment, I'm looking forward to a good result. Will post results as circumstances unfold.

does idle drop when u hit the brakes?

at first i also thought i'll just increase idle. ran my car rich like there was no tomorrow.

if ur car is idling there jus step on the brakes a few times and see if idle changes or fluctuates. if it does disconnect the vacuum hose, seal is off (i used electrical tape) step on brakes again and if idle saty normal then u have a problem with brake booster.

but u may have a leaking master cylinder or a stuffed booster. easiest way to determine which one is ****ed is using a zip tie or string.
if the car uses an abnormal amount of brake fluid then u may have a dodgey master cylinder. pull the connector (if there is one) for the vacuum hose off at the booster and dip the zip tie(long) or string into it.pull it back out and see if there is any brake fluid at the end of it.
if there is new master cylinder.
if not new booster

Let us know what the source of the vacuum issue was.