Turbo 304 massive over fuel event

[Vrv8hz]

So this has happened twice now. Driving along the first time in and out of boost. Pulled over to the side of the road and then took off again giving it a hard time. Cut out up in the revs and wouldn't start again. After turning over a couple of times began locking up. Pulled the plugs and got a waterfall of fuel out of all cylinders.

Changed the oil checked some wiring swapped ecu checked earth's. All seemed fine. Car drove fine next few times so I thought maybe all was now good.. lol nope.

The second time, a couple of weeks later (today). Car was idling for a few minutes and got back in and put in drive. Drove forward a couple of metres and cut out. Turned over a couple of times and started to hydro lock Pulled plugs and another waterfall.

Thinking I should look at possible corrupted bin and recheck injector wiring for shorts etc.

I'm putting this post up to see if anyone else has had a similar issue, or if anyone has anyone suggestions on what could cause this.

I am running an 808 with 12p, 80lb injectors, nvram. The car has been driving in the current state for the last 4ish years but I did just recently change the engine loom to tidy things up.

Appreciate any ideas you guys might have or if anyone has had similar experiences.

[vlad01]

Fake injectors?

[Vrv8hz]

I got the injectors off The1 back in the day. They have been going well for years. Would injectors go wide open all at once?

[vlad01]

If they were fake, there can be all sorts of issues but all 8 at once is unlikely.

Could be in the tune, or some weird yet to be found electrical problem.

I had issues with 34lb injectors flooding the shit out of my new engine a number of years ago despite everything being adjusted right as far as triple checking goes. I wrote up about it actually and the discovery of the scalar setting called min crank BPW. The default is like 6 or more ms, maybe 10ish ms, can't recall exactly, so what this seems to do it limit the lowest pulse the cranking can ever be despite the values in the 1st and 2nd stage tables. So no matter what, my engine always drowned with fuel if the engine even slightly didn't fire on the very first revolution of the crank so to speak, and like you, fuel drenched plugs and cylinders, fuel in oil etc... And since we are talking raw pulse width, it doesn't care on engine size, and is proportional to the injector flow rate for a given value. So if 34lb did this to my engine, 80lb would be more than twice as much and hot engines always want less than stock cranking fuel due to bigger cams.

So probably a triple whammy for you.

This might not be the problem, but one very often missed as it's not commonly known or taught when tuning the Delco and like mentioned I was the only person as far as I am aware that figured this out some years ago, 2017 or 2017 iirc.

The people who've had no problems and not known of this had been lucky enough that their particular combos weren't that effected by it to be even noticed.


Figger crossed that's all it is. I just make it a bit smaller than the lowest value you know you'll use in both cranking tables and you're good to go.

Also check the fuel reg, some can leak fuel into the vac line and ruin an engine.

[pman92]

If it's hydro locking, that would take a lot of fuel. More than just a leaking injector.

Either a fuel reg leaking, fuel coming in through the evap system (carbon canister).
Or I guess a wiring issues that is shorting all injectors (or atleast one bank of injectors) so they are permanently open. Although I'm not convinced even that would cause a hydro lock (there would only be fuel coming in when fuel pump is on).

Since it only does it sometimes, unlikely to be a fuel reg.

I would be looking into the evap system

[VTXU8]

I only had this problem when my ecu died in my 304 vp. It constantly grounded the injectors so they would spray continuously with just the ignition on. Flooded so bad that fuel was leaking out the headers. But from what i read, you have swapped ecu and made no difference. I would probe all of the ground wires on the injectors to see if there is any continuity with ignition off. Seems to do it when car has reached a certain temp. So i would test injector grounds if the problem presents itself again asap.

[Ken]

I am running an 808 with 12p, 80lb injectors, nvram.

If I was in the same situation as you, I'd be putting the tune that's on the nvram onto a memcal and seeing if the nvram is causing the problem.
I know when they lose charge they lose the contents of the tune, what happens if it's close to doing so, do odd things like this happen.
Just a thought, not saying it's the cause.

[Deuce]

I am running an 808 with 12p, 80lb injectors, nvram.

If I was in the same situation as you, I'd be putting the tune that's on the nvram onto a memcal and seeing if the nvram is causing the problem.
I know when they lose charge they lose the contents of the tune, what happens if it's close to doing so, do odd things like this happen.
Just a thought, not saying it's the cause.

And to add to this, it would be going to it's default mode that bypasses the tune. Therefore spraying what it thinks are 19lb injectors....

[vlad01]

Don't know what happened to my post, but fuel reg can def dump a shit ton of fuel. My Nephew's buick swapped 4runner would hydro lock all the time from the fuel reg filling the cylinders between key on and attempting to crank.

Just to give an idea on fuel amount, the v6 compression volume is around 60 something ml. So there would have been more than that in at least one or more cylinders in just a short time when the key was left on for a bit before actually cranking.

But this only happened when attempting to start, during running it was just a bit rich iirc.


Also, regarding the evap, could something like a pressurising event from boost somehow cause the release of fuel back into the manifold when boost is finished? eg, boost fills the fuel tank and then a rush of fuel comes back? Normally the evap system can't store any more than a mere ml or so.

[antus]

if you can catch it when its doing it and have a laptop connected and try logging the PCM you'll know if the nvram is running properly or not. If you are getting a smooth feed of data without interruption while its happening its not crashing and over fueling in backup fuel mode. If the data stops while its happening, then it likely is.