93 Silvia running lean, I need some other opinions

[cheap_sticker05]

Okay so here is the situation. My car has a pretty basic setup and ran fine prior to me putting a ISIS intake manifold, front mount, and intake pipe on the car. The car was already tuned for 550cc injectors, s15 t28, tomei pro cams, at 13psi. (rom tune)
Right after I started the car up with the new stuff on, the car would not idle right. Adjusted tps, and iacv. Got the idle somewhat under control, then noticed the car still didn't feel right so I did a boost leak test. I found a few major leaks, good, should run better now. Nope it ran worse, in boost it would completely break up and have no power even down low. Bought a wideband, installed that, reset timing thinking it was a little out even though I had never touched it. I also fixed the exhaust leak at the manifold to turbo. Now here is where things got worse. Found that the timing was a bit advanced from when i got the car. I set it back to stock and its even worse than before. My afr's are a bit rich at idle 13.0 to 13.5, probably just the tune, and the second I give it any gas it goes straight to 16-17 afr and breaks up bad. I am so lost what to do next. This car was fine until I put this crap on there.

What I have done so far-
-boost leak test, both on hot motor, and cold, found leaks and fixed them
-verified tps voltage was at .45 when closed
-adjusted iacv to get idle down
-verified all the injector ohm readings are correct and that all checked out fine 13ohm
on all
-tried mafs, and coil packs/harness from a known good car
-afr's are 13.0 to 13.5 at idle, anytime the gas is hit it goes straight to 16-17afr and
never goes lower in boost
-fuel pressure checks out 37psi w/ vacuum 43 without

Please give me some suggestions what to do next. I don't know if I should change the tune? I would just put the car back to stock like it was, but thanks to my mom and her eye for aluminum, my intake has now been recycled with the aluminum cans -_-

[PyR0NiAk]

This all falls down to either something really simple (vacuum lines being hooked up wrong, for example), or your tune.. There's no way the isis intake mani is screwing over your car. Go back through everything you unhooked when you changed it.

[cheap_sticker05]

Vacuum lines shouldn't be an issue, I have each line, wastegate, bov, fpr, pcv, and brake booster going to their own vacuum port. Its a long shot but bypassing the coolant passages on the throttle body doesn't cause a problem does it? I looped the lines just like they came out of the throttle body. From what I read that is mainly to keep the blade from sticking in cold weather and just another way of keeping the engine cool.

Also, is it even possible that the intake, manifold, and front mount could flow that much better it messes up the tune? It just seems like that wouldn't be the issue, it would only cause me to not get the most out of the parts.

[PyR0NiAk]

It definitely wouldn't hurt your tune.

By own port do you mean you used the injection ports as Vacuum sources?

[cheap_sticker05]

vacuum source, each one has its own on the new intake.

[PyR0NiAk]

The isis manifold has the same amount of vacuum sources on the intake as the stock one. The 3 holes at the bottom are for meth injection. NOT for vacuum.

[cheap_sticker05]

oh wait, really? I will change that now!

[cheap_sticker05]

So, just plugged the ports under the manifold and moved them to the ones under the throttle body. No difference. I found a guy on another forum who had this same problem last year and hope he contacts me back.

[PyR0NiAk]

Now that we know it's not a vacuum issue, let's move on to fuel. What kind of pump are you running?

[cheap_sticker05]

I am running a walbro 255. I just bought a new one because mine sounded kinda sad, also rewired it at the same time with 10g wire and relay.

Deatschwerks 550cc injectors, and stock fpr

[PyR0NiAk]

You've done SOMETHING when you changed that manifold..

Next thing to check is your spark... Check all of your plugs

[cheap_sticker05]

all plugs look whitish, like when its lean. I am going to burn new chips for my ecu tuesday when I get the cable for my programmer. I really think its something to do with the ecu. I went through all my grounds again. Cleaned them all and put dielectric grease on them.

I am hoping that its because I didn't unhook the battery the whole time I worked on the car and I may have shorted something out when I was moving wires around.

[PyR0NiAk]

plug gap?

[cheap_sticker05]

I had them gapped at .040" then dropped them to .038" after I was getting some misfire.

[PyR0NiAk]

try .032

[cheap_sticker05]

Alright, regapped them to that. It idles more rich now, but still have the same issue under boost. Its not quite as bad now, as it stays in the mid- 15's. ( no I am not beating on it)
I went ahead and verified the timing was correct again. Found another problem I believe though. When I unhook the tps after shutting the car off, it idles at 2k rpm. If I use some vice grips and crimp the iacv hose in the right spot I can get the idle back down. I am assuming now that my iacv is stuck open, but will that cause it to go lean in boost?

Waiting for the car to cool down then I am going to take it off and clean it again, and test it while its out.

[cheap_sticker05]

so, looks like the iacv is bad. makes sense why I have such a high idle. AND i cleaned this when I put the intake on.

[DeatschWerks]

That could be the culprit. If it is stuck open, then it is pulling in air behind the MAF, so it's unaccounted for air.

[PyR0NiAk]

it's nice seeing a sponsor step in and help. Good job DeatschWerks.

[cheap_sticker05]

Well still waiting on iacv to come in, should be here tomorrow then I will update.

Thanks Deatschwerks

Pyroniak, thanks for the suggestions so far, hopefully this is the whole problem

[cheap_sticker05]

Well alright, got the iacv and installed it this morning. Definitely made my idle more stable and my afr's at idle are more rich now. Same problem though. The second I hit the gas it goes really lean.
I boost leak tested again today just to make sure and there is no leaks.

Re-flashed my ecu, which made no difference (even though my k-value was off somehow)

I ended up putting a stock ecu, mafs, and stock fuel injectors in, but didn't change anything.

I am calling aem in the morning and seeing if maybe my sensor is bad. There is just no way that doing all of this and it acts the same each time.

[PyR0NiAk]

Maybe an exhaust leak before the sensor...

[cheap_sticker05]

Not an exhaust leak I am 100% sure of that. I just put new gaskets in not even 2 weeks ago, actually right before I got the wideband. I used to have a real bad leak.
Also, tested my sensor out according to the aem youtube video (haha thanks Stephen Papadakis) and my sensor is fine.
I am to the point I need another set of eyes to come look at this. I know it is something stupid and easy.

[Jmantxexport]

I had the same issue it turned out to be the O2 sensor

[cheap_sticker05]

stock o2 sensor?

[Jmantxexport]

Oem replacement but it was in my wiring harness there was a short when it was repaired car ran like new again

[cheap_sticker05]

Well, replaced the o2 sensor since I don't know the condition of the old one. It puts out a good signal all the way back to the ecu. Still no luck.

[PyR0NiAk]

Maybe you busted an injector installing the rail into the mani... Injectors are really all you have left man...

[cheap_sticker05]

Yeah, I am going to try and find another set locally. I really hope it fixes it. Might just throw some stock 370's in just to see if it fixes the problems for now.

[PyR0NiAk]

You would have to have a tune for them...