I just drained my oil (finally starting on my winter todo list ), and the oil has a decently strong gasoline smell to it. To my knowledge it didn't smell like that when I put the car away, and never smelled like that before (except one time when I had ignition problems, flooded the engine, and fouled the plugs). I'm pretty sure the fuel accumulated in the oil after the car sat all winter. So I'm assuming (and praying) the rings are ok and there's no blowby. So what else could it be?

I did a search, besides bad rings looks like the most likely thing is a bad/leaky injector...I saw something else mentioned about a pinhole leak in the FPR diaphragm. Are there any other possibilities? How do I diagnose leaky injectors? Just pull the injectors 1 at a time and see if they seem to be damp (or dripping )? The posts I saw in my search said if the injectors leak I should get them professionally cleaned. Since the car is still parked, could I take just the injectors somewhere, or would it be easier to just bring the whole car? How much would it typically run to get them professionally cleaned?

oh btw the car has about 90k on it. changed the fuel filter last fall, all maintenance is pretty well up to date.

 

The only way to really test and clean them is on an ANSU machine. I think Racetronix has one. Maybe TPIS and LPE. If the car is gonna be down for a bit anyway, that is what I would do. Of course for around $200 you can get brand new FMS injectors anyway, so you may want to go that route.

 

As stated, they can be tested, but the cost of testing is near as much as new set. I would let the car sit, no starting or priming the pump, pull the injectors and see if any are wet.

You could also prime the pump, turn it off and see how quickly the fuel pressure leaks down.

-Shannon

 

You can test them by lifting the fuel rail with injectors attached up off the intake manifold. It is easy.

Then, use the over ride wire(little brown one by the PCM) to run the pump. Place a little plastic cup under each injector. Let it run for 15 minutes, and check for drips.

Paintcan caps work great for the collection cups.
If it doesnt leak, your injectors are not the cause.

Also take off the vacuum hose to the FPR and check for fuel in it. It should stay dry.

 

so if the injectors are leaky it's not worth cleaning them? Do I have to replace all of em or just the leaky one(s)? I'd assume if 1 injector is gummed up enough to be sticking and leaking, the others are gettin there too...

just from quickly trying to get prices, it looks like they're $70 each at autozone . I could get some 30 lb injectors for half that!

I know I don't need the bigger injectors now, but down the line I'm going heads and cam, and hopefully deep 11's NA...I'd hate to swap out all the injectors for stock replacements now and do the job again in a couple years...but I don't wanna deal with programming for bigger injectors at the moment

 

Josh dont buy injectors from the dealer. Get them from thunderracing or jegs....the whole set will be around $200 something.

 

ok, I pulled the fuel rails, and as soon as I did I smelled gas. So I'm thinkin it's quite likely a leaky injector or 2 (or 8). I ran the pump for a few seconds, and didn't see anything dripping, so I put a chunk of paper towel under each injector and ran the pump again, then went away for a while to see if it would slowly leak...nothin. So I ran the pump for closer to a minute, started smelling gas, but so far didn't see any dampness on the paper towels....gonna let it sit for a lil bit again and see what happens.

I pulled the vacuum hose on the FPR, it's dry and has no fuel smell, so that's not the problem...now what?

edit:
tabahr, you mean hook the wire up and let the pump run for 15 minutes straight? I'll hafta rig somethin up I guess...don't wanna stand there holding that wire forever How much of a drain will the fuel pump put on my battery by running that long?

 

So you cannot detect any leaking gas anywhere with the system under full pressure.

hm.

Do you have a FP guage in the test port? If so, what is the pressure, and how long does it hold pressure after you stop the pump?

I use a testwire with a clip on it so I dont have to hold it. 15 min was a rough estimate. I figure if it doesnt leak a drop in 15 min it is most likely not going to leak at all.

 

no gauge...if I don't see a leak soon I guess I'll hafta go pick one up...would be handy to have anyway. I could smell fuel, so it's leaking somewhere, I'm just not seeing visual evidence...

yeah, figgered on using alligator clips...I just don't have any handy...I can twist a wire and shove it in the connector or somethin I guess...

 

if it does leak, how much leakage can I expect? The biggest thing I have handy and in a good quantity are beer bottle caps...or are those gonna overflow within minutes?

 

I tried bottle caps, ran the fuel pump for 10-15 minutes. I could smell some fuel, but not super strong. None of them had any real fuel in them...but the ones on cylinders 3 and 6 seemed slightly damp...like where the nozzle of the injector was touching the inside of the bottle cap, there was a slight damp ring that seemed like it could be gas...it was hard to tell by smelling, my hands sorta smell like gas, and the bottle cap had a strong Yuengling odor

Could that slight dampness after 10 or 15 minutes be enough to consider it "leaky"? Or am I gonna hafta pick up a pressure gauge and test things further?

Could the fuel in the oil be caused by anything but blowby, leaky injectors, or leaky FPR diaphragm (I know it's not from fuel not being burnt, ignition system is in perfect shape)? Or is it definitely gonna be one of those 3?

 

The injectors or the FPR can be the only things leaking into the engine.

At this point, I would recommend changing the oil, driving it 1000 miles and then testing the fuel. It could had just been a fluke. You may not ever notice it again.

You may want to pick up a guage and do a leak down test like I described above. It should hold pressure for quite a while after the pump stops. But... if the checkball in the pump is bad it will leak out, and that will not put fuel in your oil, it just leaks back into the gas tank.

 

ok, sounds like a plan. I'm just kinda worried though, because if the injectors aren't leaking and the FPR isn't leaking, that could mean bad rings . But I definitely smelled fuel when I pulled the injectors up, and when I ran the pump.

Ehh, who knows...

thanks