Fuel pressure bleeding down and fuel in the oil is a classic sign of a leaking/stuck injector.

 

Agreed - my worry is, why is there no oil. Did the injector leak/spray enough fuel to cause a hydrolok situation and crack a piston. We'll know more this weekend.

 

….or enough gas to overfill the oil pan and cause a oil gas mix to get ingested through the PCV system. Gas floats on top of oil so you might only see gas on the dip stick.
The oil had to go somewhere. If it’s not in the coolant and not on the ground then the car ate it.
once you solve the problem check the cats for overheating.

 

I like you. You're speaking messages of hope and joy. Lol I hope you're right! I'll know more this weekend.

 

Update -

Drained the oil and had lots of oil... And probably a gallon of gasoline. Talfryyn, this sounds consistent with your idea - how do I check the injectors? What else should I check? Oil filter and magnetic drain plug are metal free.

 

Fuel injector tester. You could try a quick check by removing all spark plugs and switching ignition on. Do not start the car, obviously..

With that amount of gasoline in oil you do have a risk of damaged bearings and possibly a bent connection rod (those unsuccessful starts). But maybe it'll run fine after fixing the gas leak.

Edit: you're right about possible piston damage too. If you don't want to pull the heads, do a compression test and camera check at least.

 

A gallon is a lot. You could pull spark plugs and use one of the USB snake cameras that connect with a phone to look into the cylinder and see which one has gas dripping. A drip in any would mean a stuck injector. Go to a FLAPS that has the free tool rental and rent a noid light set. use that to see if an injector has a bad driver or short to ground so it is always on.
Otherwise turn the ignition to run and leave it for a bit and see if one injector is getting warm.
If not electrical pull the fuel rail and pull the injectors. A proper way to check for leaky ones is to get one of the plastic adaptor caps that couple the injector to a aerosol can of injector cleaner. You need a power source to pulse the injectors to clean them but a leaking one would spray with no power applied. A less proper way I have done in the past is turn the pressure on an air compressor down to 40 or so PSI and couple the injector to a air nozzle with some rubber hose to see if it leaks under pressure.

 

I guess I'm trying to decide if I should yank the motor now and do a tear down vs going peace meal while it's in the car.

I have pulled 7 of 8 spark plugs. #8 was being difficult so we called it a day and went to dinner. 4 of 7 plugs show signs of being 'washed' in the oil/gas mix. No damage to plugs or mechanical regapping.

This makes me so mad, I just put a new petris opti, waterpump, Bosch injectors, plugs, and plug wires, and heater core on this car in the last several months. It was finally running good and now this happens. Okay rant over.
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Wont make any progress today I'm taking my father to the Carlisle Chrysler Nationals to look at cars that run.

Thank you for the continued advice.
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Did you keep track of where the "4 of 7" came from? Random or all from the driver's side?

 

I had an ECM failure many years ago that caused all of the injectors to remain full on when the ignition switch was on. Same thing as yours, lots of gas in the crankcase, wouldn't start unless I pulled both INJ fuses and cranked for a while, then ran for a few seconds only. No codes were thrown. New ECM (and oil change) fixed it.

 

Yes they are all numbered in a tray but I won't be able to get to them this evening. I'll post pictures when I can.

How did you diagnose the bad ecm?

 

Process of elimination. All of the injectors were flowing all the time when key was on, stopped when INJ fuses pulled. So, something was grounding both banks at the same time. Unlikely to be two shorts on opposite sides of the engine in different cable bundles. New ECM (exchange) at that time cost about $50, so it was a pretty low risk to try it. Solved the problem.

 

Update -

Well we got it running beautifully for one day. All I did was change the oil/oil filter and I had previously pulled the computer just to make sure it didn't have water in it or something and so it sat on the shelf for about a week.

We put the computer back in and for giggles I stuck the key in and cranked and it actually turned over. So as I just said changed (added) oil and a new filter reinstalled spark plugs, stuck on my fuel pressure tester to watch that and key to run it held just north of 40psi of fuel pressure so I cranked it and it fired up on the first crank.

We let it idle and all signs point to happy car. (good oil pressure, fuel pressure, coolant level, no nocking, surging, tapping, clicking, etc) So celebration ensued and we shut it down and went to dinner.

Today I go to fire it up and notice that when the key goes to run fuel pressure jumps to 40+ but then immediately bleeds down. Unsurprisingly, it was no longer happy (but still cranked).

Disconnected all the fuel injector pigtails and once again turned key to run - fuel pressure spiked to 40+ and immediately bled down - Talfryyn, you've got me convinced I have a stuck injector.

My plan for finding which one(s) it is is to disconnect the fuel rails with injectors still installed and stick it in a big plastic tray and turn the key to run and see which one(s) dump fuel.

If there is a better way I'm open to it. But overall I'm calling this good news engine isn't dead. Computer isn't dead. And injectors are still under warranty.
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Where did you get your injectors? Fuel Injector Connection and South Bay Injectors have been recommended on this forum. I bought a set from FIC for my 93 Vert and they worked great. 92&93 corvette EMC’s are known to have solder issues on their circuit boards. This can cause intermittent problems. You can send it to SIA Electronics for testing and repair. They will reflow the circuit board and test it.

 

I got my injectors from Fuel Injector Connection.

I'm leaning towards stuck injectors since it's bleeding fuel pressure even with the injectors disconnected from their pigtails. Makes me think (hope) the computer is actually okay.

 

Definitely is one or more stuck fuel injectors. I pulled all the spark plugs. Turned the key to run (no cranking). Fuel pressure spikes to 40+ and then bleeds down. No gas is showing up running out of the cylinders, but if I manually open the throttle body strong gas fumes from inside the intake manifold.

I've reached out to Fuel Injector Connection (where I purchased the injectors) to see about return/test/exchange. I guess I'll see how good their customer service is. These injectors haven't even processed two full tanks of gas since they were installed.

 

When you tear it down look inside or swab the fuel rails. See if there are any debris or grit or gunk.
has the car ever sat for a while with ethanol gas in it?

 

No - we have owned it a year just this week. The only times it has been sitting was when it wasn't running otherwise my wife daily drove it. The injectors were replaced because I was tearing the motor down to do the opti and figured - may as well do injectors at the same time and minimize downtime. Like I said before these injectors from FIC don't even have two full tanks of gas through them.

 

Update -

God is good and the vette is alive!

Fuel Injector Connection is great to deal with! I emailed them about the sticking injectors. The next day a full set of replacements were sent out and today I got them with a return label so I can send in the existing units for evaluation.

The new units are installed and the vette is holding fuel pressure and fired right up!

I'm going to now do a series of progressively longer idling sessions to make sure everything is okay. Assuming no issues arise I'll change the oil/filter again to ensure all fuel is out of the oiling system.

However I may actually make it to Corvettes at Carlisle after all!

 

What type/brand injectors exactly were those that failed? Were they new or rebuilt/cleaned? Just curious. Thanks -