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HELP! Raw Fuel coming out of exhaust manifold after new injectors
Hey guys I have a 94 4runner with the 3.0 and I've been chasing a misfire since I bought it in February.
So far I've replaced ALL spark related items and my intake boot since it had ripped.
I got it running good enough to put 10k miles on it since then. However it wasnt 100% so i figured, its injectors.
So I started it and unplugged the front left injector and got no change. So I went ahead and ordered injectors since they may have never been done. I ordered the Bosche 4 hole injectors and installed them two days ago. After install and reassembling everything, fuel sprayed out of the hoses going to the idle up valve on the power steering assembly and it died. I put the hose back on and tried again.
I had to keep the throttle open a bit to keep it from dying. It sounded great if I kept the rpm at 1k. My buddy was keeping an eye on everything under the hood and he told me to kill it so I did. I looked and there is literally raw fuel coming out of BOTH exhaust flanges where they bolt to the mid pipe. Enough so that with only running it for 30 seconds, there is a puddle of fuel on the ground. The heads were done before I bought it and appear fine, there are no other leaks and I'm kinda lost. Any help would really be appreciated.
Hey guys I have a 94 4runner with the 3.0 and I've been chasing a misfire since I bought it in February.
So far I've replaced ALL spark related items and my intake boot since it had ripped.
I got it running good enough to put 10k miles on it since then. However it wasnt 100% so i figured, its injectors.
So I started it and unplugged the front left injector and got no change. So I went ahead and ordered injectors since they may have never been done. I ordered the Bosche 4 hole injectors and installed them two days ago. After install and reassembling everything, fuel sprayed out of the hoses going to the idle up valve on the power steering assembly and it died. I put the hose back on and tried again.
I had to keep the throttle open a bit to keep it from dying. It sounded great if I kept the rpm at 1k. My buddy was keeping an eye on everything under the hood and he told me to kill it so I did. I looked and there is literally raw fuel coming out of BOTH exhaust flanges where they bolt to the mid pipe. Enough so that with only running it for 30 seconds, there is a puddle of fuel on the ground. The heads were done before I bought it and appear fine, there are no other leaks and I'm kinda lost. Any help would really be appreciated.
With the key in the run position measure for the voltage supplied to the injectors on the injector banks "#10" and "#20", if you have battery voltage here its not a pinched shorted wire and its the injectors.
Okay so I took the manifold back off and changed the oil. Oil was full of fuel as well as the intake canisters. I hooked everything up right and double checked everything and it's all hooked up right. All I can think is the FPR is bad now and stuck open? Idk. If I unhook the hose on the FPR L, as soon as I turn the key to on it dumps fuel out of that hose as if the FPR is constantly open. Any ideas guys?
Also possible and highly.probable that you hooked the fuel return line to something other than the fuel.tank...
could you possibly give me any pictures on where the return line hooks up to? I took pictures before I disassembled everything and hooked it all up accordingly but that could be possible I suppose.
Also, I'm not sure which hose is send and return coming from the idle up valve 🤷˟♂️ lol
.... I hooked everything up right and double checked everything and it's all hooked up right. .... If I unhook the hose on the FPR L, as soon as I turn the key to on it dumps fuel out of that hose as if the FPR is constantly open. Any ideas guys?
Originally Posted by Brandon Stralow
...Also, I'm not sure which hose is send and return coming from the idle up valve 🤷˟♂️ lol
The idle up valves (there are THREE of them -- which one are you talking about?) are just valves. They have two vacuum lines, and you can hook them in either order.
Are you sure you "hooked everything up right," or are you "kinda lost"? If everything is hooked up right, then you won't have fuel leaking from the exhaust manifold. Take a picture of your setup (particularly BOTH ends of the fuel return hard line).
You said you "unhook[ed] the hose on the FPR." There are at least two hoses on an FPR, one is fuel under (lower) pressure, and the other is vacuum (from the Fuel Pressure Control system). If you disconnected the VACUUM line from the FPR and fuel came out (and everything else is connected correctly) then the FPR is bad. If you got fuel out of the return line instead, well, that's what's supposed to happen.
The idle up valves (there are THREE of them -- which one are you talking about?) are just valves. They have two vacuum lines, and you can hook them in either order.
Are you sure you "hooked everything up right," or are you "kinda lost"? If everything is hooked up right, then you won't have fuel leaking from the exhaust manifold. Take a picture of your setup (particularly BOTH ends of the fuel return hard line).
You said you "unhook[ed] the hose on the FPR." There are at least two hoses on an FPR, one is fuel under (lower) pressure, and the other is vacuum (from the Fuel Pressure Control system). If you disconnected the VACUUM line from the FPR and fuel came out (and everything else is connected correctly) then the FPR is bad. If you got fuel out of the return line instead, well, that's what's supposed to happen.
these two lines are the lines coming from the idle up valve on the power steering. Are those the fuel lines you're asking about?
Yup, you're pumping fuel directly into the plenum (upper intake manifold) through the power steering idle-up.
To be sure, disconnect the vacuum hose from the hardline labeled fuel return. If it were ACTUALLY the PS idle-up, you should get nothing but a connection to the atmosphere. Instead, fuel will come out.
Next time you take off the plenum, draw a diagram of the hardlines underneath. It will help you a lot.
Yup, you're pumping fuel directly into the plenum (upper intake manifold) through the power steering idle-up.
To be sure, disconnect the vacuum hose from the hardline labeled fuel return. If it were ACTUALLY the PS idle-up, you should get nothing but a connection to the atmosphere. Instead, fuel will come out.
Next time you take off the plenum, draw a diagram of the hardlines underneath. It will help you a lot.
How do I fox it though? I disconnected that fuel return line. Should I connect it somewhere else or leave it open or???
Yup, you're pumping fuel directly into the plenum (upper intake manifold) through the power steering idle-up.
To be sure, disconnect the vacuum hose from the hardline labeled fuel return. If it were ACTUALLY the PS idle-up, you should get nothing but a connection to the atmosphere. Instead, fuel will come out.
Next time you take off the plenum, draw a diagram of the hardlines underneath. It will help you a lot.
I disconnected it and fuel just runs out when I turn the key to ON. What does that mean?
Edit: 22-RE (4-cylinder) Fuel return line: it attaches to the bottom of the fuel pressure regulator, located on the firewall end of the fuel rail, and the other end goes into the firewall.
This is a six cylinder. The regulator is on the left of the engine near the throttle body. It then routes under the plenum to the right hand side of the engine.
It might be near the same place on the firewall/fender.
The best way to be certain is follow the hard lines from the tank to engine bay.
11-09-2018, 09:19 AM
