All 4 cylinders full of fuel?

[Mr Whiskey]

What sensor or component would allow all 4 cylinders to be full of fuel. When I say full, I mean swimming! Seems to me one of two things happened. Intectors stayed open when we shut it off (bled line preasure into cyls), or injectors went wide open as soon as we hit the key.

I have no idea what would cause this and hope someone here might be kind enough to point me in the right direction.

This is my sons car. So we drive it to church Sun. night and it runs perfect, but when we come out it wont turn over. Thought starter of course, wasn't. Long story short, pulled all 4 plugs (had too, motor would not turn over) and hand cranked engine with ratchet and socket. Raw fuel pours out of all 4 plug holes as you turn motor. (Motor turns free now that all that liquid has somewhere to escape.) You could see it pooled up in the cylinders before I turned motor. It is deffinatly gas, not water or oil.

I know once we solve the problem I'll have to do an oil change and replace the plugs.

Some back ground; 85 gl 10 wagon, original 61k miles, ea82 mpfi (it is mpfi, one year only on fwd models) non turbo, automatic.

The fine folks here at USMB have already helped me be the "hero" for my Son once before and I'd sure appreciate it if ya could lend your expertise again.

Thanks to any and all in advance, and thanks for a fine site to come and seek help, peace.

[naru]

Leaky injector most likely.

 

ECU or wiring fault possible though.Any codes showing?

[john in KY]

Check the fuel pressure regulator. Pull the vacuum hose. If fuel drips out then replace the FPR. Can't believe all 4 injectors opened for some reason but i guess anything is possible.

[robm]

With MPFI, is there any way for a single injector to cause all 4 cylinders to fill with gas? If not, then:

 

The ECU went nuts?

 

Or the transsitors in the ECU that go to ground to fire the injectors all shorted out?

 

These seem unlikely, but so does 4 pistons full of gas.

[naru]

Check for 12V on both sides of the injectors(connected) w/key on to rule out unwanted grounding.

Edited March 4, 2010 by naru
details,details

[WoodsWagon]

My 86 MPFI turbo did the same thing. What mine was doing was cycling all 4 injectors on and off while it was sitting there with the key on engine off. It was making a click mabe 2 times a second? So it would feed in all the residual fuel under pressure in the lines. It also wouldn't run when it was doing this, you could get it to idle off of the fuel it was injecting, but couldn't drive it.

 

Sometimes it would run fine, then like someone flicked a switch it would go into this mode. Whenever power was going to the ECU, it would be cycling the injectors. I never got around to fixing it, my origional intent was to crank the boost and blow the engine, then do my EJ swap.

[Mr Whiskey]

Thank you all! I will check the fuel pressure regulator and voltage to injectors. I don't really know how to check codes on this car, might have to have someone else look into that.

The more I think about it I guess I need to listen to see if injectors are cycling with key off. We were parked for about an hour and when we tried to start it it only turned about 1 time, then stopped hard, like cylinders were already full of fuel. I'm thinking like 91Loyale said, it feed residual fuel line preasure into cylinders while it sat in parking lot. Any idea what might cause it to do that, on all 4 cylinders? 91Loyale never diagnosed his.

Opionions, suggestions, best guesses greatly appreciated! Thanks, peace.

[3eyedwagon]

Check the engine temp sensor, and its' plug.

 

Improper resistance readings will cause the ECU to load the cylinders full of fuel. I've seen a couple hydrolocked engines caused by this.

[Mr Whiskey]

Thanks 3eyedwagon, a friend of mine that used to own one just told me the same thing. Gonna check that next. Any idea what the voltage and resistance readings should be? How much should one cost? Thanks again, peace.

[themoneypit]

Thank you all! I will check the fuel pressure regulator and voltage to injectors. I don't really know how to check codes on this car, might have to have someone else look into that.

The more I think about it I guess I need to listen to see if injectors are cycling with key off. We were parked for about an hour and when we tried to start it it only turned about 1 time, then stopped hard, like cylinders were already full of fuel. I'm thinking like 91Loyale said, it feed residual fuel line preasure into cylinders while it sat in parking lot. Any idea what might cause it to do that, on all 4 cylinders? 91Loyale never diagnosed his.

Opionions, suggestions, best guesses greatly appreciated! Thanks, peace.

IIRC to check the codes on these, the computer is up under the steering column. it will have a flashing light on the front (remove lower plastic panel to see it). when you turn the key on, count the flashes. longer flashes are intervals of 10, and quick flashes are intervals of 1. example 3 long flashes and 2 quick flashes is code 32.

[Cougar]

I have to think the fuel pressure regulator is bad. It would be my first suspect at least.