There is a screw inside the TB that can adjust the closed position of the plate. You would have to drill out the rivets to get to it. I doubt that it was messed with since most people don't know it exists and tend to want to drill the TB plate.

 

Thats more like it. Fired it up, ran it for a few minutes to get it warmed up and it settled into a good idle. This lasted about 7 minutes before the engine died. I think I've burned thru another 5 gallons of gas here, as the PW was rising and rising and AFRs kept getting leaner and leaner til it eventually died. I think more fuel was pushed out the exhaust as liquid than was actually burned. I got a 7 minute datalog of it running, so I can actually answer questions accurately now. At idle, itd pull down to below 30 absolute KPA, so I don't think there are vacuum leaks after all.

 

Once I get more gas I'll see if I can get it idling and free-revving to the point of possibly actually driving it today.


The good news is that its no longer running so rich its making a mess of the driveway. Most of the gas has evaporated from the exhaust pipes so its beginning to not stink anymore either

 

Just filled it up with gas, and I'm back to uncontrollably rich again, to the point where gas is dripping out the wastegate

 

I think its time for new spark plugs before I mess with this any more. Might buy two sets, I cant imagine theyll last more than a few minutes before fouling again

 

there is no way gas would be dripping out the wastegate.

Your car has a serious problem. If that was really gas, your car poses a significant explosion hazard.

 

Its gas, trust me. I don't know what the previous owner did to this thing, but I'm really wishing I hadn't bought it.

 

why out of the wastegate? WG should be closed. What turbo system are you running?

Weird that as you fill up the tank the problem worsens.
Have you pulled your fuel pump basket out?


30kpa Absolute means you are pulling a higher vac at idle and it looks like your idle is down at a reasonable level.

 

is that injection time .419 seconds or .000419 seconds? Seems like a very short injection time, like shorter than the latency.

 

I imagine its dripping out the wastegate because they aren't really designed to seal against liquids. It's also an open dump, so it's easily noticeable when it is leaking. I don't know if this actually has anything to do with the fuel level, but I'd think it should get worse on an empty tank as fuel pressure would fluctuate on those last few cups of fuel. I'll change the spark plugs and see if it gets better. At this point I can't tell if it's running on 5 cylinders due to a fouled plug or if an injector is just free-flowing. It does seem odd that it ran perfectly fine for a brief time before going back to what it was.

Injection times I saw were between 1.5ms and .4ms. Not sure how the haltech includes the latency in that or not. The values are going to be pretty low since the injectors are large, but I see similar numbers with the 75lb/hrs on my 240sx. The 240 does have lower opening times due to the injectors being low impedance, but if this idled fine once at .400 then it should do it again. There's something else going on here.

In the meantime, I've reinsured the turbo S13 as it's pretty apparent that this isn't making it on the road anytime soon.

 

I've got a compression tester, so maybe while the plugs are out I'll test the compression as well. I'm thinking plugs might be what's holding me up here, pending any serious wiring faults in the main harness.

 

wastegates are normally closed and open with pressure. I doubt you can build enough pressure to open the WG if it can barely idle.

I have open dumps.........still closed until i build 5lbs of boost which for you that would 135kpa, or triple to quadruple to what you are seeing at idle.

why is 02 corr 1 even shown and negative? Would think it would be positive to get that 13.1 closer to 14.7. Also, not running dual widebands so how are you using the 02 corrections?

Wonder if the gas has eaten the wastegate seal.

 

I'm not too worried about the wastegate at this point. It doesn't audibly leak when the engine is running, I just don't think it's seal is designed for liquids. Either way there should not be that much (or any) liquid fuel in the exhaust system.

I think you have that backwards on the O2 correction. It's negative to pull fuel out, trying to lean it from 13.1 to 14.7. The exhaust on this car isn't factory, it eventually comes to a Y pipe which is where the wideband is.

 

Yeah you are correct about the negative.

I would turn off 02 corrections. That was a large correction for just an idle.

Exhaust leak can cause corrections to be off.

 

It does sound like an exhaust leak in multiple regards.

Wastegates (even cheap ones) seal pretty damn tight when they are shut.

Don't start that thing indoors if it's just spewing gasoline. You're asking for a catastrophe. And get a fire extinguisher or two on hand. That way you can keep your pubes from burning off when the thing goes full metal retard and pulls a NOS explosion.

But seriously. Something sounds truely jacked here. Pull your plugs, and pull off the plenum, check the seals on your rail. I've seen people's fuel injector o-rings leak like a **** and cause random gas to get everywhere.

 

i still dont see how gas is leaking out 300*++++ degree wastegates.

your cylinders would so washed down, they would be ruined in a minute

 

There's no way it's coming out the wastegates. I'm willing to bet its a leak somewhere on the line and the wastegates are just nearby where the fuel is *dripping*. Either way this is a recipe for a sh*t storm.

 

exactly, exhaust gas molecules are far smaller than liquid molecules in gasoline so a gas would leak out of the wastegate before a liquid would. when i first fire up my car I get a little condensation dripping out of my vband post turbo

I would turn off o2 corrections as well. If there is an exhaust leak by the o2 sensor it would read lean and then cause the car to dump tons of fuel to fix a lean condition that doesn't exist.

I'm confused how the car is actually firing the cylinders and running yet pouring fuel out of the exhaust valves. If the cylinders fire then the fuel should be burned up. If raw fuel is collecting in the exhaust then you would have to have a cylinder that was not firing and just dumping the fuel out of the exhaust valves.

 

try unplugging all ur injectors and just crank it over for a while... see if fuel still leaks/comes out. Maybe one injector is stuck.

Or perhaps your regulator is shot and giving full pressure to the injectors.

 

Sorry for the delay, I work odd hours which is why I don't have as much time to work on this as I'd like.

I did try turning off O2 correction, but as the engine was so rich it needed to come down by a ton anyway. The last few times it's been running rich it's sounded like its dropped to 5 cylinders, so it is actually pushing unburned fuel into the exhaust. I haven't messed with the car in a couple of days as I haven't had time to change the spark plugs yet.

The fuel leak is 100% for sure coming straight out of the wastegate's dump tube. It's running that poorly. The wastegate can't even get hot enough since it only runs for a few mins at a time at most (usually only a few seconds). I've stuck my head under the car and seen it firsthand pouring straight out of the dump tube. It's not leaking from above; it's coming from a cylinder which isn't firing. Trust me, I thought the same at first and I took the plenum off twice to look for leaks which weren't there.

One of the cylinders isn't firing consistently, which is how all of this is getting into the manifolds to begin with. I am hoping I'll find one of the plugs completely fouled upon removal to at least give me a cause.

Speaking of unplugging injectors, the one time I got it running great was after I shut them off in the Haltech and cranked the engine over for at least 30 seconds. The wastegate dripped a bit as the last of the fuel was expelled from the cylinder(s) but it cleaned up and didn't leak a drop once the engine had started after re-enabling the injectors.

It's not looking like I'll have much time to work on the Z today, but I promise to have a meaningful update this weekend