very unusual fuel leak, help!
04-18-2009, 03:02 PM
#1
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very unusual fuel leak, help!
As some of you know, I have been having a severe cylinder 5 misfire for some time. I am about to take it to the dealer soon and let them deal with it. The last time I started my 98 SE, there was lots of unburned gas coming out of the exhaust (not too much white smoke). All of this, by the way, happened immediately after I replaced my IACV because the car wasn't idling properly.
But anyway, today I was in my car today trying to figure out what was wrong and for some reason I kept turning my key between "acc power" and "on" about 2-3 times (don't ask why). I immediately started smelling fuel and started to hear a dripping sound from under the car. Sure enough, there was a puddle of gas under the car. The fuel seems to be leaking from somewhere right above the exhaust manifold, just left (passenger side) of the EGR. This is very troubling, because the leak seems to be right near where cylinder 5 is
. I have no idea what to do. Please help!
But anyway, today I was in my car today trying to figure out what was wrong and for some reason I kept turning my key between "acc power" and "on" about 2-3 times (don't ask why). I immediately started smelling fuel and started to hear a dripping sound from under the car. Sure enough, there was a puddle of gas under the car. The fuel seems to be leaking from somewhere right above the exhaust manifold, just left (passenger side) of the EGR. This is very troubling, because the leak seems to be right near where cylinder 5 is
. I have no idea what to do. Please help!
04-18-2009, 03:11 PM
#2
FWIW it's to the right, not the left.
Are you judging the location from underneath the car? Have you not examined the hoses in the engine bay yet? That's going to be the only place it'll leak from (99% of the time).
Look around the engine bay, feel all of the hoses, look for wet spots.
Are you judging the location from underneath the car? Have you not examined the hoses in the engine bay yet? That's going to be the only place it'll leak from (99% of the time).
Look around the engine bay, feel all of the hoses, look for wet spots.
04-18-2009, 03:19 PM
#3
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What's FWIW?
I looked everywhere in the engine bay. The fuel lines that go to the injector rails are fine...everything around the fuel filter is dry. But just to the left of the egr, I saw fuel dripping from somewhere right above the exhaust manifold. I am completely surprised and stumped.
I looked everywhere in the engine bay. The fuel lines that go to the injector rails are fine...everything around the fuel filter is dry. But just to the left of the egr, I saw fuel dripping from somewhere right above the exhaust manifold. I am completely surprised and stumped.
04-18-2009, 03:23 PM
#4
What's FWIW?
I looked everywhere in the engine bay. The fuel lines that go to the injector rails are fine...everything around the fuel filter is dry. But just to the left of the egr, I saw fuel dripping from somewhere right above the exhaust manifold. I am completely surprised and stumped.
I looked everywhere in the engine bay. The fuel lines that go to the injector rails are fine...everything around the fuel filter is dry. But just to the left of the egr, I saw fuel dripping from somewhere right above the exhaust manifold. I am completely surprised and stumped.
When you say left, do you actually mean to the left, or do you mean to the passenger's side?
So you checked the return line as well? And the line below the filter?
To the side of the EGR what? Guide tube, valve, solenoid? There's nothing over there that'll leak fuel.
Can you post a picture of where you think it is?
04-18-2009, 09:53 PM
#5
I had a similar situation where I had gas leaking out of the exhaust between the ypipe and catalytic converter gasket. The problem was that I had installed an EU with a bad injector driver which grounded all injectors all the time (injectors stuck open) and I had no fuel pressure because every time the pump tried to build pressure, the injectors would dump all the fuel into the cylinders.
Just an idea, you might have an injector that's stuck open and you're leaking gas from the rear exhaust manifold. I would check the injector on cylinder 5.
Just an idea, you might have an injector that's stuck open and you're leaking gas from the rear exhaust manifold. I would check the injector on cylinder 5.
04-19-2009, 10:05 AM
#6
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FWIW == For What It's Worth.
When you say left, do you actually mean to the left, or do you mean to the passenger's side?
So you checked the return line as well? And the line below the filter?
To the side of the EGR what? Guide tube, valve, solenoid? There's nothing over there that'll leak fuel.
Can you post a picture of where you think it is?
When you say left, do you actually mean to the left, or do you mean to the passenger's side?
So you checked the return line as well? And the line below the filter?
To the side of the EGR what? Guide tube, valve, solenoid? There's nothing over there that'll leak fuel.
Can you post a picture of where you think it is?
http://www.youtube.com/watch?v=wu7V3LsRm9M
It's a little confusing but it's been taken from the passenger side. Tilt your head to the left to get the perspective. The redish brown looking thing is the EGR, and just to the right of it the fuel is coming out from somewhere...
04-19-2009, 10:08 AM
#7
Even better, I just took a video of it. Here is the link:
http://www.youtube.com/watch?v=wu7V3LsRm9M
It's a little confusing but it's been taken from the passenger side. Tilt your head to the left to get the perspective. The redish brown looking thing is the EGR, and just to the right of it the fuel is coming out from somewhere...
http://www.youtube.com/watch?v=wu7V3LsRm9M
It's a little confusing but it's been taken from the passenger side. Tilt your head to the left to get the perspective. The redish brown looking thing is the EGR, and just to the right of it the fuel is coming out from somewhere...
The only thing I can imagine is somewhere along the rear fuel rail, something is spraying fuel upwards onto the bottom of the UIM, and it's going all the way back there.
Next thing I'd do is pull the UIM.
04-19-2009, 10:16 AM
#8
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Well assuming it is actually fuel (which would be very odd for that location), then...
The only thing I can imagine is somewhere along the rear fuel rail, something is spraying fuel upwards onto the bottom of the UIM, and it's going all the way back there.
Next thing I'd do is pull the UIM.
The only thing I can imagine is somewhere along the rear fuel rail, something is spraying fuel upwards onto the bottom of the UIM, and it's going all the way back there.
Next thing I'd do is pull the UIM.
04-19-2009, 03:16 PM
#10
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I had a similar situation where I had gas leaking out of the exhaust between the ypipe and catalytic converter gasket. The problem was that I had installed an EU with a bad injector driver which grounded all injectors all the time (injectors stuck open) and I had no fuel pressure because every time the pump tried to build pressure, the injectors would dump all the fuel into the cylinders.
Just an idea, you might have an injector that's stuck open and you're leaking gas from the rear exhaust manifold. I would check the injector on cylinder 5.
Just an idea, you might have an injector that's stuck open and you're leaking gas from the rear exhaust manifold. I would check the injector on cylinder 5.
04-19-2009, 03:20 PM
#11
This is most likely the problem. So apparently, my EGR gasket wasn't sitting properly (as seen in the pic below). This is where the fuel is dripping from, which can only mean one thing. One or more of the injectors is stuck open. I have seen that while the engine is off, the intake valves on the cylinders remain closed. This means that one or more of the injectors is stuck open while the injector rail pressurizes, and the gas then fills up into the UIM, thus leaking from the EGR port on the UIM. I am not sure how to go about testing the injectors. Any thoughts/input would be greatly appreciated. TIA.
Honestly, for the fuel to drip out of the EGR port, it'd have to rise up almost the entire length of the UIM. The chance of that happening and your car pretty much ever starting is extremely slim, and it would take quite a long time with the pump going for that to happen (it only primes the system for a quick burst, ~2 seconds).
Pulled the UIM yet?
The only real way to test if the injectors have physically stuck open is to pull the rail, and turn the key on.
04-19-2009, 04:58 PM
#12
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Yes, you'll just have some codes because of it.
There's always going to be a few valves hanging open, even slightly, with the engine off. Just the nature of how the cams work.
Honestly, for the fuel to drip out of the EGR port, it'd have to rise up almost the entire length of the UIM. The chance of that happening and your car pretty much ever starting is extremely slim, and it would take quite a long time with the pump going for that to happen (it only primes the system for a quick burst, ~2 seconds).
Pulled the UIM yet?
The only real way to test if the injectors have physically stuck open is to pull the rail, and turn the key on.
There's always going to be a few valves hanging open, even slightly, with the engine off. Just the nature of how the cams work.
Honestly, for the fuel to drip out of the EGR port, it'd have to rise up almost the entire length of the UIM. The chance of that happening and your car pretty much ever starting is extremely slim, and it would take quite a long time with the pump going for that to happen (it only primes the system for a quick burst, ~2 seconds).
Pulled the UIM yet?
The only real way to test if the injectors have physically stuck open is to pull the rail, and turn the key on.
But yeah, when I did the whole "acc power" to "on" this morning it took a good 10-12 tries before any fuel started coming out of the EGR. So I guess it could still be a possibility. I agree with you, I am going to pull the rail and then try it. I will post again after it's fixed, or if I notice anything else. Thanks for the help everyone!
04-20-2009, 07:05 AM
#13
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There is no way your filling the UIM with fuel to the point it leaks out.
If that were happening, the first crank of the engine would hydro lock it on fuel alone.
You have a fuel line/rail leak somewhere.
My .02
If that were happening, the first crank of the engine would hydro lock it on fuel alone.
You have a fuel line/rail leak somewhere.
My .02
04-20-2009, 08:45 AM
#14
If he's got ONE injector stuck open and he's priming the system 10-12 times and all the fuel pressure is being relieved into ONE cylinder, and if you've got an exhaust valve hanging open on that cylinder, is it possible the fuel is leaking into the exhaust system and into the EGR system through the EGR port on the exhaust manifold? It's extremely hard to believe you're filling up the UIM with fuel.
On another note, check the injector harness. The ECU supplies the injector with ground when it wants it to fire. When the car is not running or cranking, the injector should not be seeing any ground. Check to see if this is true for the injector harness on that cylinder.
On another note, check the injector harness. The ECU supplies the injector with ground when it wants it to fire. When the car is not running or cranking, the injector should not be seeing any ground. Check to see if this is true for the injector harness on that cylinder.
04-20-2009, 08:57 AM
#15
If he's got ONE injector stuck open and he's priming the system 10-12 times and all the fuel pressure is being relieved into ONE cylinder, and if you've got an exhaust valve hanging open on that cylinder, is it possible the fuel is leaking into the exhaust system and into the EGR system through the EGR port on the exhaust manifold? It's extremely hard to believe you're filling up the UIM with fuel.
On another note, check the injector harness. The ECU supplies the injector with ground when it wants it to fire. When the car is not running or cranking, the injector should not be seeing any ground. Check to see if this is true for the injector harness on that cylinder.
On another note, check the injector harness. The ECU supplies the injector with ground when it wants it to fire. When the car is not running or cranking, the injector should not be seeing any ground. Check to see if this is true for the injector harness on that cylinder.
Short answer: Completely implausible.
04-20-2009, 09:12 PM
#16
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If he's got ONE injector stuck open and he's priming the system 10-12 times and all the fuel pressure is being relieved into ONE cylinder, and if you've got an exhaust valve hanging open on that cylinder, is it possible the fuel is leaking into the exhaust system and into the EGR system through the EGR port on the exhaust manifold? It's extremely hard to believe you're filling up the UIM with fuel.
On another note, check the injector harness. The ECU supplies the injector with ground when it wants it to fire. When the car is not running or cranking, the injector should not be seeing any ground. Check to see if this is true for the injector harness on that cylinder.
On another note, check the injector harness. The ECU supplies the injector with ground when it wants it to fire. When the car is not running or cranking, the injector should not be seeing any ground. Check to see if this is true for the injector harness on that cylinder.
No, not a chance. Because for one, fuel wouldn't travel from the intake to the exhaust valves, it would drip straight down into the cylinder. Two fuel would have to go against gravity to go into the EGR tube into the valve. The fuel would then have to make it's way completely through the valve and piping, to the top of the EGR guide tube at the UIM.
Short answer: Completely implausible.
Short answer: Completely implausible.
I am still wondering how to test the injectors, should I just remove all of the injectors from their housing (while still having their wires connected), as opposed to removing both rails from the LIM?
04-20-2009, 09:14 PM
#17
Well, today I removed the IACV to get a good look inside the UIM. I could see that there was fuel in there, and there was some fuel accumulated by the EGR. So, a considerable amount of fuel is getting inside the UIM somehow. It definitely is hard to believe that the UIM can fill up that much with gas, but perhaps more than 1 injector is being grounded open while the key is turned from "acc power" to "on?"
I am still wondering how to test the injectors, should I just remove all of the injectors from their housing (while still having their wires connected), as opposed to removing both rails from the LIM?
I am still wondering how to test the injectors, should I just remove all of the injectors from their housing (while still having their wires connected), as opposed to removing both rails from the LIM?
Pull up both fuel rails, set them on a piece of cardboard or something, and turn the key to on. You'll see which either puts out a lot more fuel, or is completely stuck open.
04-20-2009, 10:18 PM
#18
Pull up both fuel rails, set them on a piece of cardboard or something, and turn the key to on. You'll see which either puts out a lot more fuel, or is completely stuck open.
04-20-2009, 10:24 PM
#19
If they're laying against a piece of cardboard or similar, the fuel won't fully atomize, and it'll go straight back into a liquid form. Then the only thing you'd have to worry about is the fumes in the air, and even then combustion is unlikely.
Cigarettes will not ignite liquid fuel, no matter how much the movies seem to think it does.
Cigarettes will not ignite liquid fuel, no matter how much the movies seem to think it does.
04-21-2009, 08:39 AM
#20
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No, if you remove them from the fuel rail, they won't be getting fuel; you won't know which is stuck open.
Pull up both fuel rails, set them on a piece of cardboard or something, and turn the key to on. You'll see which either puts out a lot more fuel, or is completely stuck open.
Pull up both fuel rails, set them on a piece of cardboard or something, and turn the key to on. You'll see which either puts out a lot more fuel, or is completely stuck open.
Let's just assume that one or more of the injectors is stuck open, as this is most likely the case. What do I do then? Replace the injector?
04-21-2009, 09:07 AM
#21
Oh, okay. So, just to be clear, it's perfectly normal for all of the fuel injectors to ground and put out some fuel when the key is in the "on" position, even if it's just a small amount (besides the one that will be stuck open)? I was under the impression that when you turn the key to "on," only the fuel rail pressurizes; and then when you crank, the injectors start to ground. Correct me if I am wrong.
Let's just assume that one or more of the injectors is stuck open, as this is most likely the case. What do I do then? Replace the injector?
Let's just assume that one or more of the injectors is stuck open, as this is most likely the case. What do I do then? Replace the injector?
No, you're right, the injectors shouldn't spray when it primes the system.
Though if one is stuck open, then you'll see it spraying.
If one is indeed stuck open, you can just replace that injector.
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