I'm here begging for any information someone may have to offer. Thanks in advance.

My Truck: 01 Durango 4.7L engine 2WD


My problems:

Gas mixing into oil tank.

Low MPG (4-8 when I normally get around 18)

Spark Plugs excessively dirty after only a couple of months (very thick black gunk on them)

o2 Sensor failure.

Heavy black smoke from exhaust.


Steps I've taken so far:

When I first noticed the drop in MPG and the black smoke I went to get a error code check run. It came back as o2 sensor (bank 1 sensor 2), and also Bank 1 too lean. I changed out the sensor it indicated. This did not fix either of the problems. So I figure I'd check my plugs. I did this and noticed the dirtiness of them. After changing them there was still no positive effect. I checked my oil level after and noticed the smell of gas and that the oil was much too thin. So I'm now at a point of not knowing where to go. I would like to try and resolve the problem myself but I have no idea which direction to take.

 

Sounds to me like your injectors are bad. They could be leaking when the engine is off.

 

+1 Sounds like you have an injector or two leaking. A quick way to determine if you are losing fuel pressure via a leaking injector, find the schroeder valve on the fuel rail. After letting the truck sit for a few hours (overnight would be best) Give it a press and see if fuel squirts out (just watch your eyes!).

I find it hard to believe you'd have more than one injector bad at a time, however.


Also, change that oil ASAP before running the engine any longer!

 

I checked the valve this morning, It had no pressure.

I took the truck to have it looked at. The mechanic checked out the injectors and says they are not leaking or stuck. He won't be able to look at it anymore until tomorrow.

Any other ideas guys? I've had someone suggest that it may be a leaking fuel pump gasket. Could that be it?

 

Fuel pump is in the Gas tank - not sure how one can relate a problem with that, to all your symptoms.

Were all your plugs oily or a just one or two? Suggest doing a wet/dry compression test.

 

the fuel pump gasket could be the lack of fuel pressure in the a.m. but none of the other symptoms, i wouldnt worrya bout that one right now, figure out why you have gas in the oil, fix it and go from there.

 

Yes, all the plugs were dirty.

I am hoping to find out about the gas in oil tank. It is orobably my highest priority. Still I have no idea why it would be.

 

the only reason i can think of is a stuck open fuel injector i mean thats the only entry point for the fuel into the engine.

idk what the test is for that, but if its a slow enough leak you wont be able to tell easily.

 

They'de have to bench test the injecors to find out right? Unless one fails enough the trip the mil and log a code? Ask your mechanic HOW he checked your injectors,and have him do what GV suggested,wet and dry comp test,find out if the rings are weak and you have excessive blowby,and if your valves are seating correctly...
From the FSM:

(engine off) is a normal condition.

 

I would also think this is injector leak. I just don't know of any other way it could get into your oil after atomization when the engine is running. It would have to be leaking down into the cylinder when the truck is off.

It also makes sense on the fuel mileage. I would pull em out and have them individually cleaned and checked or simply replace them all, but that will run ya about $30-40 bucks a piece. However you could go to a junk yard and pull a set out and install them in your truck, however install new O rings first. Then ship yours off or clean you new ones. There is a few home made videos on www.youtube.com that will show you how to clean yours in a home made device using a can of cleaner and a tube, along with a 5 volt power source. Of course a real shop would be better then anything, but I'm just saying. Also look into the service manual as there is resistance checks to check them to see if they are good, but understand that even though the resistance checks come back ok doesn't mean the injector isn't stuck open.