redlinetuning

I've posted this in the Forced Induction section, but I figured I'd get it here as well, as it pertains to my 98 Civic DX

Here's the build:

Engine/Drivetrain Modifications:
B16A
81.5mm 9:1 CP pistons w/ coated skirts
Eagle Rods
ACL Bearings
balanced rotating mass
ITR waterpump/oilpump
shortblock blueprinted
GSR head
Skunk2 Pro manifold
ARP hardware
ACT 6-puck unsprung
ACT 12# flywheel
GE blockguard
T3/T04e 50Trim
top mount manifold
HKS SSQ bov
Greddy Profec B EBC
Hondata S300 p28 (Handcommand)
3" downpipe - 3" flex by VRD Garage
removed cat
Apexi N1 bpipe to canister
27x9x3 intercooler
Cometic HG .053"
Autometer boost, EGT,oil temp, oil pressure guages
AEM UEGO wideband
3BAR MAP
BLOX vacuum manifold

now that I have the IACV check engine light fixed (re-pinned ECU wires), cleaned out the IACV, double-checked and re-soldered the MAP and TPS wiring (correct), replaced TPS, I’m still getting a sporadic idle up and down from 1000-2000 rpm, sometimes even 2500, when engine is warmed up or hot (190* oil temp). During cold start-up, idle sits between 2000-2500 rpm, a tad high. I tried lowering the fuel pressure at the FPR from 45 down to 32, 35, 40, but still, nothing. The wideband meter was reading 11-13 at 45psi (FPR), at 32psi, AFR ~17+ at 3000rpm @60mph, a bit lean, so I turned it up, kept going. AFRs are now at about ~15 cruising speed limit.


1. Tested the IACV/idle adjustment, didn't do much.
2. Set FPR back to 45psi, where it originally was.
3. Tested each vacuum line at the vacuum manifold.
4. Replaced vacuum line to PCV valve
5. TPS calibrated to .5v

I'm not getting any CELs, but still a sporadic idle as if the TPS was not getting correct voltage. If I pinch and hold anyone of the vacuum lines going to the vacuum manifold, idle seems to stay constant at 1000rpm warmed up.

blox vacuum ports (left to right)
|------------|
1. evap purge
2. 3BAR map
3. pcv valve
4. boost controller/boost guage
5. wastegate
6. can't remember. will look and update

I'm trying to trace for any other vacuum leaks, but can't seem to find anything.

Can anyone chime in?

Thanks.

kaiba

Get a can of part cleaner and spray around to find your leak.