My FD is close to stock. In the course of wiring in an FC-Tweak setup and first using the wrong wideband wires, I managed to flood the heck out of the engine. I was able to unflood the combustion chambers pretty well but there is oily fuel leaking off of the turbo manifold and rear downpipe gasket.

Is there any advice on how to recover from this without starting an engine fire? At the moment I've cracked the downpipe-cat joint and about a tablespoon full of oily gas has drained off there. Probably at least that much has leaked out of the turbo manifold. I'm going to wash off the turbo manifold with brake cleaner and let it dry thoroughly but I'm concerned about pockets of fuel in the turbos and cat.

I have considered pulling the turbos but that takes me several hours and it could do more harm than good.

 

Oil can get into your turbos if you overfill the engine with oil and it runs up and into the vent pipe on your oil filler neck and down into the intake elbow on the front turbo; Assuming you still have a stock set up.

But you probably know that already.

Big risk of snapping of nuts and studs in pulling old turbos and exhaust manifolds.

Are you seeing residue in your cross pipe? That might indicate fluids in your turbo.

 

Oil level was mid-dipstick before this, but good thinking to ask.

I'm thinking maybe the oil is thick because it's not unusual to get some oil in the bottom intercooler pipe and through all of this the oil blew through instead of burned. So it would be a good thing if this is basically just oil and not oily fuel.

So then the risk becomes an oil fire more than fuel. I know that oil leaks in the turbos are considered a nuisance more than a fire hazard, but then that assumes the oil burns up in the engine rather than coats the interior of the exhaust side.

The more I think about this the more I'm considering pulling the intercooler piping and turbos.

 

Never been in the situation…at least not this bad. Following. Regardless good to see the OP’s username come up. Welcome back.

 

Would it be easier to start with the exhaust pipe after the downpipe.. Removve it and,

use a big shop vac to blow through the cat,, muffler and tailpipe, to see ii anything much comes out?


The few instance I have heard of where an owner overfilled the oil, was that the result was a lot of smoke from the oil burning off in the turbo.

Was Mazda not worried about that sort of thing when they routed the vent pipe to the front turbo intake?



@DaleClark

 

If you are still running an OMP and you where cranking ihe car a lot to get the excess gas out, would not the oil ,mixed with the gas have come from the OMP?

Or have you got your remix ratios wrong. I have seen that happen.

And maybe you have a very bad tank of gas (or diesel?).

 

never been in this situation but like you already did, I'd undo the downpipe and let it drain and evaporate as much as possible, put it back together and wash with brake cleaner and then with the water hose
then just start it and spray the turbo area with the hose and let it warm up and burn everything inside the turbos+exhaust. it should clear itself in a few minutes idling

 

In addition, I would pull the fuse so the car doesnt get spark, but you can still crank. Maybe the pulses from the motor would help force any residual out.

 

Drop the oil, disable spark and fuel, add a couple quarts of oil (doesn't need to be full, just enough to pick up and pressurize while cranking), crank it for 10ish seconds at a time 3x, let it sit for an hour, repeat a few times, wait a day, repeat the cranking then do a proper oil change and fire it up. I wouldn't be too concerned.

 

What is the best way to "disable the fuel"?

We went with disconnecting the eletrical connector for the fuel pump found in the hatch.

 

The 'Engine' fuse in the foot well.

 

The fuel pump circuit seems to have some redundancy, we thought just disconnecting the fuse was not enough.

Others suggest one, two or three * different relays to pull.

So we just disconnected in the hatch, to remove any doubt.

(* the fuel pump relay, the EGI Relay and that green relay with no name.)

 

The car has stock OMP. Oil is under 50 miles old since engine rebuild so fuel dilution should be dead minimal. The fuel is a bit old but it's ethanol-free 90 octane and the car ran just fine on it a couple weeks ago when I took it for safety inspection.

The unflood I followed was to pull the EGI fuse and plugs. Looking at the wiring diagram, the fuel pump relays will still get power signal from ignition on, but if the injectors can't fire and aren't leaking* they shouldn't be adding fuel just because the fuel rail is pressurized. * I realize this is a big assumption so when I next unflood it I will pull those or disconnect the fuel pump power completely to be sure.

I grabbed a spray bottle from the hardware store and sprayed down the oily areas with isopropyl alcohol and wiped it all down. I don't mess with brake or carb cleaner unless it's strictly necessary. Seems to be a lot cleaner. I will next pull my SMIC piping since there's often a puddle down there and I don't need even more oil in the engine.

It's nice to see some old names here. Life has a way of pushing priorities around and leaving an FD sit causes a lot of problems but I'm trying to get it back to driving condition. It would be lovely to have it running well before winter.

 

Man oh man, I feel this. I was merrily daily driving mine because the reliable beater broke down (HAHA!), then I parked it for some upgrades and life got crazy and fast forward years passed in the blink of an eye, I had a completely rusted fuel tank and pump, all the upgrades are still in boxes and I've been slowly trying to bring it back out. My buddies jokes that I put the FD unfairly in prison and need to be freed ASAP! I'm trying! I named it Blacky because of course its black and every couple weeks I get a random FREE BLACKY! text... 😂

 

Leaking injectors could be real. Also if you have lost vacuum to the FPR solenoid, the FPR will close pushing fuel back to the injectors at higher pressure.

Twice I have had the vacuum lines to the FPR rot away.

Watch out that the little rubber plug on the Pulsation Damper has also not rotted away. That could be leaking gas in the direction of your turbos.