91 Civic SI Hatch w/a mildly built ZC.

It absolutely WILL NOT IDLE no matter what.

All the sensors are functioning properly, injectors are good, new distributor, new map and IAC.. Good ecu.

It will foul out the plugs after a couple of days because it's running rich. When it's cold and idling high (high being 15-1700) it's great and it will chirp the tires at any RPM in first gear and will roast them from a dead stop.. A lil beast.

But won't idle once it warms up, it just dies.

I think something in the throttle body, beings thats the only thing that hasn't been replaced and I believe the problem is directly related to air flow. I say this because since it's idling bad, it's an airflow problem and since it's fouling the plugs, too much air causing the ecu to give it too much fuel at a low rpm..

Any other idea's?

 

tell us about your ECU and injectors.

 

DO tell about "mildly built".....

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Natural Aspirations &raquo;</TD></TR><TR><TD CLASS="quote">DO tell about "mildly built".....</TD></TR></TABLE><TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ( o )( o ) &raquo;</TD></TR><TR><TD CLASS="quote">tell us about your ECU and injectors.</TD></TR></TABLE>

DOHC ZC block & head OBD-0

Head
Exospeed 5-angle valve job & new valve seals
NO-MILLING of head
Stock cam gears
Stock valvetrain
Stock cams with a Crower Reduced Base Circle Grind -- NOT A REGRIND(weld up lobes and regrind them to different specs)
89 Integra dizzy - new
stock cyl pos. sensor

Block
new oem pistons, rings, pins, bearings, water pump, oil pump, gaskets & seals.
Reconditioned rods, stock bolts
Overbore 0.5mm

Stock intake manifold, stock FPR, stock d16a6 throttle body, AEM SRI, stock injectors
DC 4-2-1 ceramic header, carsound cat, tanabe cat-back
fidanza 8lb flywheel, clutchmasters stage 1
rebuilt si tranny

Virgin, pulled from a running car, PG7 ECU (5sp 89 itnegra)

NEW NGK plug wires, NGK plugs (6 heat range)

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ( o )( o ) &raquo;</TD></TR><TR><TD CLASS="quote">tell us about your injectors.</TD></TR></TABLE>

X2

 

Stock SI injectors...

Sorry

They test out fine, correct ohms and whatnot.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by mac_24_seven &raquo;</TD></TR><TR><TD CLASS="quote">Stock SI injectors...

Sorry

They test out fine, correct ohms and whatnot.</TD></TR></TABLE>



<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by mac_24_seven &raquo;</TD></TR><TR><TD CLASS="quote">
I think something in the throttle body, beings thats the only thing that hasn't been replaced and I believe the problem is directly related to air flow. I say this because since it's idling bad, it's an airflow problem and since it's fouling the plugs, too much air causing the ecu to give it too much fuel at a low rpm..

Any other idea's?</TD></TR></TABLE>

How about fuel pressure? What are you running? Stock FPR? Is the vacuum still hooked up?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by mac_24_seven &raquo;</TD></TR><TR><TD CLASS="quote">91 Civic SI Hatch w/a mildly built ZC.

It absolutely WILL NOT IDLE no matter what.

All the sensors are functioning properly, injectors are good, new distributor, new map and IAC.. Good ecu.

It will foul out the plugs after a couple of days because it's running rich. When it's cold and idling high (high being 15-1700) it's great and it will chirp the tires at any RPM in first gear and will roast them from a dead stop.. A lil beast.

But won't idle once it warms up, it just dies.

I think something in the throttle body, beings thats the only thing that hasn't been replaced and I believe the problem is directly related to air flow. I say this because since it's idling bad, it's an airflow problem and since it's fouling the plugs, too much air causing the ecu to give it too much fuel at a low rpm..

Any other idea's?</TD></TR></TABLE>

No check engine lights?
Clogged PCV or improperly installed PCV?
Malfunctioning/dirty/clogged EACV?

Just some ideas.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by bambam &raquo;</TD></TR><TR><TD CLASS="quote">

No check engine lights?
Clogged PCV or improperly installed PCV?
Malfunctioning/dirty/clogged EACV?

Just some ideas.</TD></TR></TABLE>

NO CEL's
I'll check the PCV, though I'm sure it's good.
EACV is clean, already checked that.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by IT GUY &raquo;</TD></TR><TR><TD CLASS="quote">
How about fuel pressure? What are you running? Stock FPR? Is the vacuum still hooked up?</TD></TR></TABLE>

Fuel pressure is approix 38 lbs... Have a gauge in the engine compartment. And yes, the vacuum line is still hooked up.


Keep the idea's coming.. Maybe you guys will think of something I havn't :S

I'll check into the PCV tonight though, just to make sure.

 

ok. brainstorming out loud here.

When you first start the car, the ECU operates in an open loop ignoring sensor input and running on a start-up / cold map. So, when it reaches full operating temperature it switches to closed loop using inputs from the sensors. And you say this is when your car goes to hell.

I'm guessing it has to do with a sensor since it dies once it's warmed up. which one? I'm not sure there.

Is the car running rich or just fouling plugs? Plugs can be fouled by too cold of a heat range being used or retarded timing (opposite of advanced, not name calling )

I'll keep thinkin' keep us updated

 

are you getting a vacum leak around the tb or the intake gasket?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 4g hatch &raquo;</TD></TR><TR><TD CLASS="quote">are you getting a vacum leak around the tb or the intake gasket?</TD></TR></TABLE>

Thought that may have been a problem.. so I cleaned the old gasket off the throttle body with a dremel: nice and smooth/clean now

It does throw a code 17, speed sensor code (sorry I said there werent any) but thats only because it's not hooked up.

I'mstill thinkin and I've got nothing.. Tryin to get a TB lined up.

Anybody have one they'd sell me cheaply?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by IT GUY &raquo;</TD></TR><TR><TD CLASS="quote">
Is the car running rich or just fouling plugs? Plugs can be fouled by too cold of a heat range being used or retarded timing (opposite of advanced, not name calling )
</TD></TR></TABLE>

LOL I agree, it sounds funny.

I was just thinking the same thing though - have you checked the ignition timing yet?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ( o )( o ) &raquo;</TD></TR><TR><TD CLASS="quote">
I was just thinking the same thing though - have you checked the ignition timing yet?</TD></TR></TABLE>

Kinda can't check the timing, since it's not idling correctly.

I've just been having the dist. loose and turning it by hand, smoothing it out by ear. Was gonna try and RE time it sunday, but the timing light died

I'll see if I can get a video of what it's doin this weekend so you guys can better diagnose it.

 

A few things to think about.

You have a light flywheel, bigger cam, and check engine light is on.

With the first two your idle is not going to be like it was stock. Usually you have to run a higher idle.

When the car is cold it is somewhat fine but then it try's to go into closed loop and it set's your DTC and goes into limp mode. Which is not going to help.

You do have your MAP sensor hooked up correctly, like it was stock? Check your vacuum lines.

Set the idle higher, fix the vss and time it.