Thread: DE+T DTC codes help with connecting IACV and EVAP Solenoid correctly

So I've got a simple request, I've got a 96 P10 with the stock lowport DE, boosted on pretty much a GTi-R T28 set-up, OBD2 and I'm getting a P1400 EGR&EVAP Solenoid and a P0505 Idle Air code, the entire EVAP system and EGR system was pulled from the car, and I know there is a way to get P1400 and P0505 codes to be erased from the ECU I just don't know what the trick is, I'm not getting a direct EGR code since it has been flagged on Nistune, and so was my IACV but I still get a loopy/stalling idle at cold start. I currently have the EVAP Solenoid plugged in but no lines going to or from it, basically open air just getting an open/close signal; for you turbo guys out there if you could tell me how to possibly hookup the IACV hoses/lines properly or a way to bypass them as not to get a code, and also if there is a way to properly hook up the EVAP solenoid I get the code for so as not to have that issue that would be great. Unlike a lot of people I'm not planning on waiting for the last month before emissions to get this resolved, I figure the sooner I get it resolved the better off I'll be and a year ahead of time should be plenty of time to figure it out. Thanks in advance to everyone able to help

How do you have the IACv hooked up now?

Since it's a turbo setup all my charge pipes are solid so I blocked off the 5/8 hose which runs from the air intake tube to the intake manifold behind the Throttle body, and the tiny vac nipple which is at the bottom of the throttle body between the throttle coolant lines is capped off since it used to run to the EGR and BPT which I no longer have either

I'm referring to the larger hose which comes off of the factory intake tube after the MAF

Well. You're not going to be making positive pressure 100% of the time. The instances where the iacv functions, at idle, you should be pulling a strong vacuum. How is your manifold going to get a sufficient amount of air to the engine at idle with the throttle plate shut and your iacv blocked off?

As for the evap solenoid, there's no need to block everything off. I'll post a picture later of what I did.

@P10 Goodness I would appreciate that, it would give me a decent jump on getting the car emissions ready so as not to procrastinate till the last minute.

Pretty much as P10 said, you need to weld an open bung into your intake pipe after the turbo(mine's about a 1.5 feet from the TB) and run a hose between the bung and the intake manifold that you blocked off. This is where the IACV(and the AICV) gets extra air after the TB plate is closed. Most turbo guys do this. I do it. Nissan even does it on stock DETs.

Also you should use the hole in the TB that's right before the throttle plate (doesn't see vacuum) for the line for your wastegate because wastegates don't like vacuum, only boost.

-G

Awesome I'll do this then, I was just afraid of boosting the IACV to oblivion and having an issue now that hose would go After the MAF correct? I ask because my MAF is set up about 1.5ft from the Throttle body with the BOV to atmosphere flanged off of the intercooler.

Here's 2 pics to show you guys exactly what I'm talking about when I say the big hose behind the Throttle body and the small nipple below it, just so we're on the same page cuz I know pictures mean a thousand words.

This is from up close the tube on the right is the one that is plugged and I'm assuming is related with the IACV and the capped off nipple well that speaks for itself, the red thing is my FPR and above that is the Throttle Chamber to give you an idea of how everything is situated


This picture is from a little further away so you can see what's around and also get a better view of the tube which I plugged and possibly get a better idea of what's going on