I have a 93 civic hb p30 ecu.
just built from scratch ls/vtec all new bearings, rings and headgasket
used my know working b16 head never remove intake mani or fuel rail or TB or iac.
running ls crank and rods w/ p30 pistons so my compression ratio is approx 12.2:1
I have a wideband and it reads 14.5 at idle or when returning to idle from a cruising speed.
fuel pressure is 55 psi @wot and returns to 42 psi @idle.
cannot find any vacuum leaks so far.
I used one heat range colder plugs due to the compression.
engine idles just fine @ 750 rpm timing is 16 deg btc.
when coming to a stop w/ clutch in or out and pressing the brakes veh will stall.
will restart w/o a problem and never runs rough at idle.

any suggestions are appreciated

 

Bump the rolling idle in the rom. Possibly check the VSS signal to the ECU. Try unhooking the brake booster vacuum line and see what that does. Check/set idle via the helm manual procedure, clean the IAC solenoid.

Good luck and let us know if you figure it out.

 

why check the vss I dont understand? I was thinking about the brake booster. I will be trying that tonight. The iac never came off the im. veh was only down for 9 days. didnt have this problem before w/ just the b16

 

Tune it!

 

if it hasnt been done already ...then yes what he siad

 

Also that throttle body is going to choke that engine (not that it's related to the problem)

 

74MM throttle body edelbrock victor x mani. itr cams. new plugs 1 range cooler. new cap and rotor. have to wait til tuner is back in town. then hondata s300. I would think that the vehicle should at least rev down to idle w/o stalling. I dont want to sit on a dyno w/ drivability concern and get charge $100 bucks an hour.
any suggestions are greatly appreciated.

 

It sounds like something with the iacv. I have seen simialiar problems with iacv sticking open/closed and have idle drop with no load. My buddy had to drill out the Tb hole to allow more air into his because when slowing down the iacv wasnt getting sufficant air.

 

I have replaced to iacv with a known working unit, condition still is present.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 93egsir &raquo;</TD></TR><TR><TD CLASS="quote">74MM throttle body edelbrock victor x mani. </TD></TR></TABLE>

 

weekend bump for suggestions

 

i'm assuming its either a, something of a vac leak, or b, the deaccel fuel values are fucked.

 

deaccel fuel values and in the fuel mapping right?