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Cylinders are full of fuel. Please help.


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So I bought a 95 legacy auto with 160k on the motor. Did an oil change, tune up(plugs, wires, fuel filter).
I
then cleaned the engine bay and ended up getting water in my cylinders,
so I dried those out and after many attempts of getting it started it
finally started right up.
Now what it is doing is while it is
running, it is dumping fuel into the cylinders which is causing it to
smell of raw fuel out of the exhaust. Thankfully this is not my DD yet.
So
I thought it might be the injectors, so I go to take two of the
injectors out and when i take them out I see fuel dumping from the fuel
rail into the cylinder. So then I run to the fuel pump and unplug it and
by this time I ended up getting two cylinders full of fuel to the point
the car wont even turn over(I only tried twice).
So Im stuck. Ive
read it could be the Fuel Pressure Regulator, but I took the breather
hose off of it and there was no gas leaking out. Im very confused.
There is also zero gas in my oil which is good. icon_wink.gif
Any thoughts or opinions on what it could be?

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I'm not certain I follow everything but, if any cylinders are 'full' of a fluid, that is a hydrostatic lock situation preventing the engine from turning over (bad for the starter/battery) and plugs may have to be removed to push any water or fuel out. Then, before putting the plugs back in, it's probably a good idea to squirt a little oil in the cylinders to restore some compression. Fuel particularly will wash-down the cylinder reducing compression.

 

If the ECU thinks the car is getting huge amounts of air, it will dump fuel in, so, maybe the MAF (or MAP?) was affected by the engine cleaning procedure?

 

that's all I got.

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It was probably misfiring because there is water in the spark plug wells and the boots are shorting. Pull the plug wires, blow the water out of the wells.

 

After the water is out, Then you need to pull the spark plugs out, unplug the coil pack (you DO NOT want sparks) and crank the engine a few times to blow the fuel out of the cylinders. Then let the cylinders dry for a few hours.

Put the spark plugs back in after drying, change the oil because it will be heavily diluted with fuel, and only after that can you attempt starting the engine again.

 

Don't forget to plug the coil pack back in.

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not sure which engine you have, in fact, others here have a LOT more experience than I do. Just wondering if the engine cleaning knocked loose or contaminated an electrical connection or wiring. Seems like after that is when the fueling problem showed up.

 

maybe look at number 4(s) here; http://opposedforces.com/parts/legacy/us_b11/type_29/intake_and_supply_system_turbocharger/air_cleaner_and_element/illustration_1/

 

but, there are other ways the ECU might be confused about the A/F ratio and is trying to compensate with additional fuel. Inspect underneath the air intake for disconnected tubing too.

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No. No dripped fuel. Before this it started up perfectly and ran perfectly. It just ran SUPER rich. I could tell it was running rich by the smell of the exhaust was raw gas. And whenever I bought it, it had been sitting for a little while and it started right up. It just started giving me problems after i washed the engine (like an idiot).

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1 lucky Texan, when you say squirt a little oil in the cylinder will you elaborate a little bit on that? I just dont want to screw it up and put too much in or not do it right.

 

 

I dunno, a teaspoon or so. It won't be in there long and it's just to help that first few revs until oil can be distributed normally from under the piston. The car might start anyway, but it could help it start more quickly. Also, starting with the gas pedal on the floor is the 'clear flood' procedure so, if the car has pumped in too much fuel, that should help get more air in the mix.

 

maybe Ivan has some other ideas for what an engine cleaning could damage that would lead to a rich condition.

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1 lucky texan,

You have been very good at helping me think through more of what this could be. Would me not unplugging the fuel pump cause fuel to continue to flow through the rail when I removed the injectors when the key was off?

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1 lucky texan,

You have been very good at helping me think through more of what this could be. Would me not unplugging the fuel pump cause fuel to continue to flow through the rail when I removed the injectors when the key was off?

 

 

with the key off, you're just dealing with residual pressure I'd think. Same reason folks are told to pull a fuse, start the car, BEFORE changing a fuel filter. saves you from getting sprayed in the face. But that pressure should fall off quickly. The more rubber hoses in the system, the more they have to deflate. But the pressure can't last with the pump off.  But key off, the pump should not have been running. Indeed, under normal circumstances, key on, engine off - the pump only runs for a few seconds to pressurize the system. Then it comes on of course as the engine begins using fuel after starting.

 

not saying some kinda weirdness with the engine cleaning couldn't short out a fuel pump relay or ???? Just not at the top of list of possible problems I'd think.

Edited by 1 Lucky Texan
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There is a good amount of volume of fuel in the rails and the lines that connect them. With the design of these rails, when one injector is removed all of the fuel from the rail and a lot of fuel from the joining line will dump into the intake port. It's all gravity, though the sheer volume of fuel can make it appear that the pump is running, but its not when the key is off.

 

I don't think there's a big fuel system issue here. Water in the plug wells will cause misfiring, which means unburned fuel in the exhaust.

 

These engines tend to smell rich when first started anyway. It could have been running normally, and you're just not used to the way these cars are.

Worst case, the ECT sensor (engine coolant temp) is bad, and the ECU thinks the engine is -40 F degrees, which will definitely command the fuel trim way rich.

 

ECT reading to the ECU can be checked with an OBD2 scanner that reads live data. There are also ways to test the ECT sensor wih an ohmmeter, though I don't recall the exact resistance specs off hand.

Edited by Fairtax4me
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You all have been so helpful. Today (nice and sunny and getting semi warm here in Louisville, KY) I pulled the plugs, unplugged the coil pack, unplugged the fuel pump, and turned the engine over a few times. there was a ton of fuel in there. I then put a 1/2 tea spoon of oil in the cylinders to lube them up again and then turned it over by hand a few times. Thankfully no resistence which im guessing means not a huge sign of damage yet. Next is changing the oil (should I put a new filter on there also? The one on there is brand new.) and then new plugs. Letting everything dry for now.

 

Any other thoughts to this or encouragements in not making bone head choices next time?

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filter change probably not needed. I might be tempted to accelerate my next oil change a few hundred miles but, really, a tiny amount of fuel that MAY POSSIBLY be in the filter/passages, but likely not, is not gonna be an issue after the engine gets to temp for a few minutes.

 

unrelated though but, has the car ever had a new PCV valve? now might be a good time to change or at least clean that part and hose.

Edited by 1 Lucky Texan
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PCV valve was changed a week ago. I love changing those easy, inexpensive parts that make a big difference.. ;) Texan, youve been very helpful. Thank you. Ill be working on this tomorrow and see what happens.

So next steps for me is put it all back together and hope for the best?

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Oh I gotcha. That makes sense. Since the oil pump never kicked on then it never moved the oil through the filter. Great.Since we're on the subject. What type of oil do you all recommend for a subaru with 160k miles? I used high mileage 10w-30. Would you all ever suggest doing an engine clean then going to a fully synth like amsoil?

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there's almost as many approaches to the oil question as religion or politics. I'd think a name brand oil of the proper viscosity  range for your climate and driving conditions would be a great place to start. If a problem comes up, or some compression or other testing indicates, just be prepared to tweak your choice a little.

 

as for tune-up ideas, you might consider a throttle-body cleaning and/or seafoam treatment or at least a tankful with techron or seafoam.

 

brake fluid is often overlooked, and at 160K, power steering fluid might like to be refeshed. other fluids too if they haven't been changed.

 

might wanna check the parking brake adjustment. they are no automatic and the little star wheels in the back may need to be turned up a few notches.

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I run Valvoline high mileage 5w30 in mine with 215k on it now. No problems with blowby or anything else. A high mileage mix will keep these just as clean and protect as well as a full synthetic. Synthetic has some advantages but its really a waste of money for these.

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You need a scanner that can read live data. Sometimes the ones the auto parts stores use for checking codes can read live data but most of them just read codes.

You can also check the resistance of the ECT sensor with an ohmmeter, a bit more tricky, and you need to know the specs for the resistance at certain temperatures, but its still a viable method and cheaper then buying a scanner if you can't borrow one.

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OK. I will do that. Today I buttoned everything up after  letting all the fuel dry out of the cylinders. I left the hood up on a nice sunny warm day with plugs unplugged. I changed the oil with a high mileage 10w-30. (Penzoil). Then I put a teaspoon (might have been too much) of oil in each cylinder. Put spark plugs back in, etc and started it up. James bond wouldve been proud with the smoke i blew. It was white. It wasnt super thick like oil smoke is usually. and it reaked of raw fuel. I had to change my clothes it was so bad. But the car was running fine. No knocks or weird idleing. Im so confused. I just let it run for a minute but the smoke started getting worse so I turned it off. 

Not sure what to do now. I havent had a chance to check the ECT sensor or the fuel pressure but will do that next. Any other thoughts though? Could the smoke just have been burning everything off? ie. teaspoon of oil, raw gas in cylinders and exhaust pipe?

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