Just installed the cams and valvetrain and the car won't idle. Anyone have this problem?


Modified by VTEC Visions at 10:23 PM 3/28/2005

 

how are you tuning the car for those new cams?

 

maybe try opening the throttle body a little more, just to keep it going until you can tune it.

 

Take some fuel away at idle.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by VTEC Visions &raquo;</TD></TR><TR><TD CLASS="quote">Just installed the cams and valvetrain and the car won't idle. Anyone have this problem?</TD></TR></TABLE>

Thats strange, my car idles pretty good with Skunk stage3s, I say mess around with the idle screw until you get it around 900 to 1000 rpms.

 

do you have adjustable cam gears? What are they set at?
Honda's don't like to idle with aftermarket cams.....lol.
But seriously, my idle is fine and i am using Crane stage 2's with 11.3:1 CR.

 

The Pro1 cams have huge primaries like a Toda cam. That is why the idle is so rough to hodl steady. Take away some fuel at idle until it starts to steady out.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by PreStaged12s &raquo;</TD></TR><TR><TD CLASS="quote">Thats strange, my car idles pretty good with Skunk stage3s</TD></TR></TABLE>

The Pro 1's have larger primaries than the S2S3, that would explain why they idle rough(er).

 

did you change the vavle train? bent vavle maybe. could be a bunch of things..

 

i have the same problem, **** i thought i was the only one, tried everything on an AEM ems and the car would be fine around 1500, but anything lower than 1300 would be just a matter of seconds before it just stumbles down a few rpms and just dies out. no matter what i did, nothing. since i had oem injectors i plugged in a chipped ecu and it seemed to idle. lumpy but it idled.. still trying to figure it out exactly.

 

You most likely have too much fuel at idle. I had a similar problem when I dropped in my BC3+ cams, which have huge exhaust primaries. This effectively reduces vacuum levels at idle, thus the ECU thinks it needs more fuel.

Adjust TB to give motor more air at idle or tune the car.

 

This might be stupid, but is the MAP connected?

 

Lean out the fuel mix up to 2000 rpms until the idle stops fluctuating. Then adjust the TB screw so you idle around 750 rpms.

BryanPendleton explained it prefectly what is happening.

 

i was using a aem wideband and an aem ems, what would be the target AFR for idling at 750 rpms, i believe the chipped ecu was running leaner than what i was correcting the fuel to be, so thats why it idled with the oem ecu.

 

Whats your valve lash set at, may have a tight valve as well. Overly rich running at idle especally occurs with big cams. can cause poor idle

 

target afr should be 14.7-15.0 for idle.

 

750 idle is low for a big cam. also, generally speaking a stock computer will run on the rich side at idle because of the decreased vacuum inherent with a big cam at idle.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by asubennett &raquo;</TD></TR><TR><TD CLASS="quote">target afr should be 14.7-15.0 for idle.</TD></TR></TABLE>

wow!!! that lean really ?? man i was keeping it around 13.1 for idle and thought that was going to far and also i had started the motor without having done my valve adjustment since i built my head because i didnt keep any of the rockers in order so after i did the valve adjusment it didnt change jack **** and it was WAY off before. but anyways when i get another chance ima try to run it that lean. can anyone back that up?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by PS2005 &raquo;</TD></TR><TR><TD CLASS="quote">750 idle is low for a big cam. also, generally speaking a stock computer will run on the rich side at idle because of the decreased vacuum inherent with a big cam at idle.</TD></TR></TABLE>

i was actually running a chipped p06 w/ a skunk2 program, im using a 00 itr harness on my 92 civic so it has no tach wire on the right side of the harness so my tach doesnt work for now but it was idling well, lil lumpy until what sounded like 2k+ and when the rpms came down it almost wanted to shut down but it stayed on, my oil light and batt would flicker so i cant tell where it was idling but ima wire in my tach and find out.

 

DID YOU DOUBLE CHECK THE VALVE LASH?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by sickerhatch &raquo;</TD></TR><TR><TD CLASS="quote">DID YOU DOUBLE CHECK THE VALVE LASH?</TD></TR></TABLE>

yes like i said i did my own valve adjustment, intake to 8 and exhaust to 7

 

alot of fuel needs to be pulled. im having the same issues right now with a car im working on. FYI my friend had to put his AFC at-50 to idle a set of toda B's and another friend was at -30 to idle a set of RM M22's both of those cams are big

 

so it seems... learn something new everyday. once i get crome setup i can continue tuning since i dont have the ems no more.

 

Yes sir. 13.0 is too rich for idle. Plus it will be harder to get it into the sweet spot in the upper rpm's if it is to rich down low.

14.7 for idle and anything under 40% throttle is what I like. For heavy load greater than 60% throttle shoot for 13.0-13.2 afr's.

 

my friend had the same problem with the same cams. He got it to idle but it's still pretty rough, going over speed bumps or moving the car at slow speeds , the motor wants to die.