WideBodyFEELZ

@RonJ, I need your help! First off, I know I'm bumping referencing a five year old thread, but I can't send you a PM.

So I have a similar issue. My b16 has a surging/jumping idle from about 500-1200. It happens both when cold and hot. It will happens anywhere form 10-30+ seconds before and if it can figure itself out.

-No vacum leaks
-Already tried bleeding the coolant system twice
-I have no FITV (which I really thought would fix it, so I was bummed when I saw that my Edelbrock 68mm TB doesn't have one).
-The other hole in the TB (going to the TPS? or the IACV?) has a very strong suction. If I plug it the engine stalls.
-ECT - SO last night the idle was surging and I was lucky enough to pop the hood while it was happening, I unplugged the ECT and it stopped surging immediately. Taking a closer look I think I need to replace my cams seals (or vtec solenoid gasket) because some oil has dripped down onto all of those sensors.

My question is, would oil near or in the sensor totally screw it up? Should I try to clean it or replace it. I have a multi-meter and can test it as well.

As an FYI, the engine is a jdm b16 sirII with an Edelbrock turbo kit. It has been tuned with Chrome on an obd1 p28 ECU. It also has larger injectors (I'll have to look what size, I am blanking right now).

seangeeb4o9

Vacuum lines? Remember. Start simple.

WideBodyFEELZ

I can double check again, but I had a reputable shop test everything for vacuum leaks already. I'll try again.

I have not messed with the idle screw on the TB yet either after bleeding the coolant system, which I've read might possibly fix it since the system was trying to make up for the air caught? - I just found it odd when I unplugged my ECT sensor it idled perfect right away.

h22acd5

im having the sam issue the fitv was deleted and blocked when i was searching for leaks i found when i sprayed the iacv where it met the intake manifold the engine nearly stalled out could it be the gasket on the iacv causing the surging

civic402lx

Did the shop do a smoke test to check for air leak?

WideBodyFEELZ

I know they were trying to see if I had a boost leak or if any of the vacuum lines were leaking. But they may not have done it to the EVAP system now that I think about it.

I cleaned up the ECT sensor since it had oil all over it and when I was looking I found something weird. There is a hose coming from the Evaporative Emission Purge Control Solenoid Valve (EVAP) highlighted in green below that T's off to connect to my PCV valve and then nothing-One end of the T goes nowhere right now. I tried to explain this in the diagram below. I'm running a Skunk2 IM which when installed had me T off the hoses like that. It looks like it should connect back to the top of the IM, but that now connects to the blow off valve.

Where does this hose go now? I've been looking at diagrams for the past week and trying to figure it out. Could this be causing the idle issues?

civic402lx

What happen to the idle!if you plug up the hose that go to nowhere? Does it change?

WideBodyFEELZ

Nope, nothing happens to the idle. There is no suction or anything coming from the hose. I even plugged it for a day to see if anything changed, and nothing.

I keep looking to see what other people have done with their turbo set-ups. It seems that it changes around a few of those lines. The Skunk 2 manifold (I'm running) has less bungs than the Victor X manifold which looks like it would have a place for that hose on the back side.

Still trying to figure it out.

94 Civic Si

Just a quick look, but it seems to me that both PCV and Evap need some form of manifold vacuum to function properly. Connecting them, and then leaving the circuit open to atmospheric pressure does not seem correct...

WideBodyFEELZ

I agree. But there is no port left on the manifold to do that with. Other people have had to have this issue. I just can't seem to find what they did.

mk378

Get another tee so you can tee everything together to one of the ports you have.

WideBodyFEELZ

Is that weird though to have a double T going from all those places? PCV to EVAP to IM to Blow Off?

civic402lx

It doesn't hurt to try. The hose that go to nowhere, put a T there. Then one hose to your blow off valve, the other hook into the intake manifold. Which is where your current blow off valve is hook up to.. Get it?

h22acd5

when i unplugged my iacv the idle settles to a solid 750 rmp idle sounds great just has CEL what is that a sign of bad iacv??

WideBodyFEELZ

I'll try that and see if it works. I am also looking into a Edelbrock IM if I can find one for a decent price so I can do it properly.

WideBodyFEELZ

Update: I added a T to the loose vacuum line so that it now connects to the hose going between the BoV to the bung/port on top of the Skunk2 IM.

The results right away - the idle shot up to 1500. After driving two miles and sitting at a light, the idle started jumping from 1500 down to 500 then back and forth multiple times. The idle dip was almost low enough that the car stalled (red light on dash flashing at lowest rpms). This occurred for a while, I had just missed the light. Then I parked the car, got back in 5 minutes later and the idle jumped back to 1500 and then settled at 1000 at the next light. Drove home (2 more miles) without issues. Parked the car, came back 30 min later to start and it started idling at 1500 but dropped to 1000 again for the nest 2 miles.

SO It seems like it has a very similar issue still. It never dipped that low before but maybe the computer was trying to figure out the new connection. I'll drive it again at lunch and see what happens. I figure I'll give it a day or two to see if it persists.

WideBodyFEELZ

Figured I should post an update since half of H-T threads end without one. Kept having the idle issues. I swapped the IACV for a used one and replaced the ECT since it was a cheap sensor. After this, cold starts were basically not happening. The car wouldn't start cold unless I force fed it gasoline. The car would stall anytime I held in the clutch or came to a stop, basically unless I was on the gas pedal until warm. Then once warmed up, it would idle super low. Took it to have a tuner look at it and revamp the tune, still nothing, He said it was most likely the IACV or a wiring issue. He set the idle really high so that when I did'nt fix it, I would know right away.

So I bought a new IACV from Hondapartsnow.com, and 2 days / $250 later it showed up. Installed in 15 and it fixed it (for now?). The idle is up super high like the tuner said it would be. Calling tomorrow to schedule an appointment to get the idle set correctly again. Sorry for the long explanation, I figure someone might have similar problem and this may help them.

Just as an FYI, I ended up basically doing 100k tune-up at the same time I swapped the ECT and used IACV - valve cover gasket kit, timing belt (wp+t), cam seal, crank seal, vtec solenoid gaskets, etc.

Hopefully it will all be fixed by the end of the week. I forgot how annoying it is to get your engine right again. It's a real pain in the *** sometimes.

WideBodyFEELZ

Update: Car is back to normal!!! ...after new IACV / ECT sensor and adjusted tune (b16 turbo p28 w chrome).

CX-Adam

Gratz!

Can't wait until I can get my car running right.

WideBodyFEELZ

It came back! Ugh. Never ending.