Benjamin

This is seriously the most F*d up thing I've ever seen...What the hell happened?


Yesterday: we did the non-sequential conversion. I've done it on about 4 cars, and came to look over two friends who did theirs. It appeared to be done correctly when we looked at what was capped up. However, the BOV didn't work. It was late at night, and we decided to finish it this evening. This afternoon, when driving (under seemingly no boost), the crossover pipe pops off (perhaps it wasn't tightened down all the way). When the crossover pipe was screwed back on, the BOV worked fine, the previous boost issue was fixed, and the car ran great.

The car was brought to me to hook the PFC commander up to test boost levels and adjust fuel levels. The car was let cool off from the drive to my house. We got in the car, and started it. It ran for 30 seconds, and dies. After the motor shut itself off, LOTS AND LOTS of white/blue fuel smoke came out the exhaust. The key was left in the on position, leaving the fuel pump running. SOMEHOW, the fuel made it's way into the turbos, FILLED UP THE Y-PIPE, AND CROSS-OVER TUBE. BOILING fuel then spewed out the Blitz blow-off valve. You could put your hand on the cross-over tube and feel fuel GUSHING through it like a PVC water pipe. We shut off the ignition, turning off the fuel pump and fuel stopped pouring into the y-pipe. We pulled off the crossover tube to find BOILING gas in the y-pipe. WTF happened inside the motor?

-BN

DaedelGT

This sounds familiar... I wish I had bookmarked that other thead in which this happened.

911GT2

Fuel in the Y-Pipe??!?!

Holy good god, that can't be good. Only think I can think off is a lot of blown apex seals, and a seriously malfunctioning fuel pump. The motor was off, key in on position, and fuel pump was running? That just doesn't sound right to me. Is that how it's supposed to work?

Even if lots of gas was getting to the engine, after it went into the turbos, how the hell did it get to other side (I can never remember which one is the turbine, and which is the compressor wheel ) and get into the Y-pipe? Unless it came flowing back down from the TB and through the IC. Wow, whatever happened, get pics and tell us about it. Thats just not good...

93BlackFD

stuck injectors was the other problem....

teamstealth

would the injectors really push that much fuel tho to make it GUSH out the y-pipe?

lovemyseven

iTrader: (2)

hopefully you didn't do any damage to the seals inside the motor. With a little luck, the rest of the fuel may evaporate or have been burned up by the heat of the engine. Have you tried to start it yet. It may idle poorly at first but may eventually even out. You may want to disconnect the hose that leads to the IC though, I wouldn't want any fuel inside it.

turbojeff

iTrader: (30)

Your literally talking about gallons of gas here right? If the crossover pipe has boiling gas then it had to fill up the entire intake tract, IC, IC pipes.... That is a lot of gas.

EpitrochoidMan

I also remember reading a post like this. Someone else posted pic of IC piping filled with fuel. I think it might have had something to do with the PFC and having injector duty all the way up. I might be wrong but I think the other person this happened to was trying to shoot flames.

Benjamin

Alright---we pulled off one of the vacuum lines going to the primary turbo, and it was filled with gas. The Y-pipe was up to the break in the Y with gas; boiling gas. This, for me, would mean that the whole turbo assy was full of gas. Also is the lower IC pipe.

The power FC was running the base map at the time--it was installed late last week. It was done properly, and wasn't adjusted.

My personal theory: Apex seal busts, shooting metal into the turbos, tearing to pieces the turbine wheels and the seals int he turbos. Unburnt fuel in the chambers fills the Y-pipe and turbo assy. I can't, however, figure out where all the fuel was coming from. We are seriously talking 2+ gallons of fuel. Picture filling the lower IC pipe, the whole turbo assy, and Y-pipe with fuel, and still shooting a STEADY HEAVY drain out the BOV. It was like a garden hose on my driveway. We let it roll into the street in fear of burning the house down. Yes....It was WELL over a gallon of fuel, judging by what we saw in the Y-pipe, IC pipe, and on the ground.

We know the motor's shot, most likely are the turbos. The owner and I are more curious what was the chain of events leading to this happening. Any ideas?

Again, the motor shut off (I assume 'popped') at idle, less than 30 seconds after starting.

-BN

artowar

iTrader: (1)

Any chance the fuel came in the other way-- from the intake side, back through the IC, and then into the crossover/y-pipe assembly?

Benjamin

the fuel was entering at such a volume, that it seemed the injectors weren't there, and the FPR was allowing fuel to dump into the chambers. We're talking serious amounts of gas. Also, I felt the direction of the fuel flowing in the crossover tube. It was flowing FROM the Y-pipe TO the IC pipe.

Everything in this car is full of gas....Precat, turbos, vacuum lines, IC lower pipe and endtank, etc. I'm sure the cat is, in addition to the rotor housings themselves.

This is entirely too weird. If there's something I'm missing, or more info you guys need, please ask--I was very observant of what was going on.

Where's the F*ing fuel coming from? why would an injector freeze up when the motor popped? What the hell else could allow an open flow of fuel into the engine with the motor itself not actually running?

-BN

teamstealth

what if a piece of the broken apex seal went UP the LIM, and snapped off the end of a injector, making it basically a open hose that poured in fuel from the pump? Could that have happened?

artowar

iTrader: (1)

Have you pulled the injectors yet?

93BlackFD

here's my 2 cents

you're not giving me enough evidence to believe the motor is dead, ie, no compression, seals shot, etc

sounds like an injector went pop and just decided to pour fuel in your motor, filled up one rotor chamber, then the other, and then started backing up the LIM, UIM, elbow, IC, and into the y-pipe

pretty simple if you have 850cc's just spraying at 40psi....won't take long at all, and yes, believe it or not, that will choke your motor out and it will not run, might even make some popping noises or flames ;-)

teamstealth

93BlackFD

how do they know the motor's shot? i don't see any evidence....

things like, no compression, motor is seized, makes me believe that, novices drawing that conclusion from a very flooded motor, i don't buy

911GT2

That makes sense, but he said that the flow was going the other way, from Y-pipe to IC. Anything you can think of that would make it reverse direction?

Jason93RX7R1

Ben! Holy **** I can't see how Mike's car did this.

I was around with for the attempt at figuring out the non-seq conversion issues with the BOV's, and while there were some issues, I don't see how this could have happened. Can there be any relation of this to the pre-cat that we were thinking may be effecting his boost? Prior to the non-seq conversion he wouldn't be getting much boost in first, and it would fall on its face in second. In late part of second, and third, fourth etc.; he could get full boost but it would *slowly* creep up to full. I was thinking that was directly related to the pre-cat, as its the last restriction in his exhaust. (cat is a high-flow now) I certainly don't think it caused this fuel issue, but going back to some of the original BS could it have played a role with this via heat or other means?

Fuel injector gushing open sounds like its a good possibility, if it was 'uncapped' it really would just flow and fill all kinds of stuff, and kill the motor just by having it full of fuel.

I don't see how the motor could pop at idle in the driveway, under no boost.

At least you didn't catch anything on fire. Like. ... Well....blowing up your basement with your transmission.... (I really wouldn't know about that...)

J

93BlackFD

that doesn't make sense, at all, let's say he had an overlap, and fuel went in the intake runner and out the exhaust, it still wouldn't get into the compressor housings, even if the turbos were toast

it happened as i stated, he has no way of knowing where the flow of fuel went based on observations after taking it off....IMO

93BlackFD

oh yeah, and fuel pump doesn't turn on unless the car is running or in starting position, read the electrical schematics

the only way to make it run is to ground it with the diagnostics terminal

teamstealth

would a F*cked up connection in the PFC cause it to run accidentally? like a bad wire that grounded to the chassis?

teamstealth

also, lets say that the fuel couldnt have gotten through the turbo housings and seals......then where else could it have come from? Only the bottom of the IC, the y-pipe and the x-over tube were filled with gas. If it had come from the UIM, wouldnt u see traces of gas in the elbow?

-Zach

93BlackFD

yeah, the ECU grounds injectors to make them fire, if a wire is exposed, it will ground on it's own and cause the injector to stick....pull the fuel rail off, figure out which one is sticking by pressurizing the fuel system (key in on, diagnostics terminal connect F/P to GND with a small jumper wire)

if it's a secondary injector, just pull the electrical plug off it and it should stop spraying, you don't need secondaries to crank the motor, reassemble it, clean out all of the mess you made (fuel, etc)

it will crank, replace your harness or fix the bad wire

paw140

My first thought was also a stuck injector. I totally agree with 93BlackFD. Unless you aren't telling us something, you haven't concluded that the motor is popped.

turbojeff

iTrader: (30)

I can't imagine all 4 injectors sticking and dumping that kind of gas. Considering the total capacity of the injectors it would probably take hours to fill up everything with gas.