Air bypass valve, crankcase ducting

[craigztoyz]

Long story short.

I am running the rear lines from each cover to the crankcase vent in the valley. The middle two are bridged together, the front two, are t'd together and vent through a filter. ok, so I plugged the big opening in bottom of upper plenium. I left the bracket for the AIB, but the rest is all gone, or lost in storage.

Is this ok?I recall someone saying they had removed it, and it idled fine, and had no issues. looking for feedback, and info, Thank You, Craig

To help define info wanted, what is the importance, of this, andsince it is unmetered air, I can't imagine it feeds much if connected. Do I need to find the pieces?

Same with the EGR too. I removed it all, plugged it up, and now not sure what to do with the wiring connectors.

[Q45tech]

IAC is also used as an electronic dash pot to progressively drop rpm in steps when you suddenly let off throttle on highway to avoid stalls.Besides it's normall function of stablizing rpms under load of Power steering, alternator, ac system and varying air densities and temperatures.

[craigztoyz]

Thats what I was figuring, by what it does, but not sure what problems I will have, hot weather usually, hope that will be good, as a choke is rarely needed.

[T45]

I deleted both my IAC and PCV systems. Without the IAC the engine is a pig when it's cold, even in the summer. Once it's up to operating temp the idle is (was...lol) fine and once my idle speed was set I didn't have any stalling after chopping the throttle on the highway etc.

For the pcv I ran the rears to the crankcase vents, the centers together, but on the pass side I vented it and the drivers side I blocked it off. Any pressure from the drivers side will make it over to the pass side through that center hose.

[SuperHatch]

To help define info wanted, what is the importance, of this, andsince it is unmetered air, I can't imagine it feeds much if connected. Do I need to find the pieces?

The IAV does not feed the motor unmetered air. There is a pipe that runs under the plenum to under the throttle body, and a small hose that connects that pipe to the intake pipe, between the MAFS and the throttle plate. Every bit of air in the engine is metered from the factory, it is the only way to ensure proper tuning. Even venting the PCV system to atmosphere introduces unmetered air via crankcase blowby gases or releases metered air that is now unburnt. Venting the PCV system, however, is a very small percentage compared to the IAC system and will only result (if the motor is healthy) in a 1-2% change in target AFRs.

[npez]

The IAV does not feed the motor unmetered air. There is a pipe that runs under the plenum to under the throttle body, and a small hose that connects that pipe to the intake pipe, between the MAFS and the throttle plate. Every bit of air in the engine is metered from the factory, it is the only way to ensure proper tuning. Even venting the PCV system to atmosphere introduces unmetered air via crankcase blowby gases or releases metered air that is now unburnt. Venting the PCV system, however, is a very small percentage compared to the IAC system and will only result (if the motor is healthy) in a 1-2% change in target AFRs.

Craig,

To add to Steve's & Q45Tech's comments, the IACV works off of like 10 different inputs to the ECM. Also, though hot here in Texas, the input is not ambient air temp but engine coolant temp. So when you start the car and until it reaches operating temp, the IACV is in play. It also has an input for battery voltage, starting signal, and many others that determine how open or closed this valve will be.

My $.02 would be that while the car will most likely run without it, it probably will be best to track it down and install it, so you can have 100% drivability.

Thanks,Nick.
Modified by npez at 9:56 PM 7/12/2008

[craigztoyz]

Thanx Everyone for the input, This is what I was looking for.

T45- Thats exactly the reply I was looking for, I remember when you started it, those q's were brought up and went through. I wont be driving it cold, and am not worried about it. If I come across the pieces, then maybe one day.

I hope to get some vids up soon. Ground issues at the moment. Now cant get ecu to trigger anything. No pump, inj, coil. THE JOY OF $#IT THAT DOESNT WORK.