Help Me Diagnose Huge Fuel Leak
04-17-20, 11:18 AM
#1
Help Me Diagnose Huge Fuel Leak
So my car has been sitting for about 9 months as I've been busy.. I moved and also bought another car (Porsche 993) but I'm ready to get my FD sorted back out!
Last time I drove the FD I drove it to work and back without issue and left the car parked in the driveway. When I went to put it into the garage later that evening the car would barely idle and was crazy rich and blowing lots of smoke from the tail pipe. The smell of fuel was really strong and an actual puddle of fuel was under the engine once I got the car moved.
First the car is a single turbo conversion and runs FFE fuel rails, ID 2000 injectors and I custom made the fuel lines with braided stainless lines.
How would you experts out there tackle this issue?
My thought's are to check the below in the following order but I'm looking for ideas as well.
1 - Check the fuel line connections from the hard lines to the soft lines. I've already eye balled the lines and at a glance they seem ok.
2 - Is o2 sensor giving bad readings causing the ECU to dump tons of fuel to where the exhaust manifold is leaking fuel onto the ground. I have an innovate wideband feeding an old Adaptronic PnP but I don't think this is the issue. Non-the-less I'll recalibrate the o2 sensor since its an easy thing.
3 - Pull off the manifold and inspect the fuel rail for leaks at the fuel line connections and also around the injectors themselves.
4 - If still no issue found, maybe the Fuel Pressure Regulator is bad? Any tips on how to test it rather than just purchasing a new one? I have a pressure gauge on it and the PSI is where I set it to once the fuel pump primes.
5 - Maybe an injector is stuck open? What's the best method to test?
6 - Return fuel line clogged? Any ideas on an easy way to test?
Other ideas? This is not some small fuel leak so its got to be something big.
Last time I drove the FD I drove it to work and back without issue and left the car parked in the driveway. When I went to put it into the garage later that evening the car would barely idle and was crazy rich and blowing lots of smoke from the tail pipe. The smell of fuel was really strong and an actual puddle of fuel was under the engine once I got the car moved.
First the car is a single turbo conversion and runs FFE fuel rails, ID 2000 injectors and I custom made the fuel lines with braided stainless lines.
How would you experts out there tackle this issue?
My thought's are to check the below in the following order but I'm looking for ideas as well.
1 - Check the fuel line connections from the hard lines to the soft lines. I've already eye balled the lines and at a glance they seem ok.
2 - Is o2 sensor giving bad readings causing the ECU to dump tons of fuel to where the exhaust manifold is leaking fuel onto the ground. I have an innovate wideband feeding an old Adaptronic PnP but I don't think this is the issue. Non-the-less I'll recalibrate the o2 sensor since its an easy thing.
3 - Pull off the manifold and inspect the fuel rail for leaks at the fuel line connections and also around the injectors themselves.
4 - If still no issue found, maybe the Fuel Pressure Regulator is bad? Any tips on how to test it rather than just purchasing a new one? I have a pressure gauge on it and the PSI is where I set it to once the fuel pump primes.
5 - Maybe an injector is stuck open? What's the best method to test?
6 - Return fuel line clogged? Any ideas on an easy way to test?
Other ideas? This is not some small fuel leak so its got to be something big.
04-17-20, 11:56 AM
#2
Racecar - Formula 2000
So my car has been sitting for about 9 months as I've been busy.. I moved and also bought another car (Porsche 993) but I'm ready to get my FD sorted back out!
Last time I drove the FD I drove it to work and back without issue and left the car parked in the driveway. When I went to put it into the garage later that evening the car would barely idle and was crazy rich and blowing lots of smoke from the tail pipe. The smell of fuel was really strong and an actual puddle of fuel was under the engine once I got the car moved.
First the car is a single turbo conversion and runs FFE fuel rails, ID 2000 injectors and I custom made the fuel lines with braided stainless lines.
How would you experts out there tackle this issue?
My thought's are to check the below in the following order but I'm looking for ideas as well.
1 - Check the fuel line connections from the hard lines to the soft lines. I've already eye balled the lines and at a glance they seem ok.
2 - Is o2 sensor giving bad readings causing the ECU to dump tons of fuel to where the exhaust manifold is leaking fuel onto the ground. I have an innovate wideband feeding an old Adaptronic PnP but I don't think this is the issue. Non-the-less I'll recalibrate the o2 sensor since its an easy thing.
3 - Pull off the manifold and inspect the fuel rail for leaks at the fuel line connections and also around the injectors themselves.
4 - If still no issue found, maybe the Fuel Pressure Regulator is bad? Any tips on how to test it rather than just purchasing a new one? I have a pressure gauge on it and the PSI is where I set it to once the fuel pump primes.
5 - Maybe an injector is stuck open? What's the best method to test?
6 - Return fuel line clogged? Any ideas on an easy way to test?
Other ideas? This is not some small fuel leak so its got to be something big.
Last time I drove the FD I drove it to work and back without issue and left the car parked in the driveway. When I went to put it into the garage later that evening the car would barely idle and was crazy rich and blowing lots of smoke from the tail pipe. The smell of fuel was really strong and an actual puddle of fuel was under the engine once I got the car moved.
First the car is a single turbo conversion and runs FFE fuel rails, ID 2000 injectors and I custom made the fuel lines with braided stainless lines.
How would you experts out there tackle this issue?
My thought's are to check the below in the following order but I'm looking for ideas as well.
1 - Check the fuel line connections from the hard lines to the soft lines. I've already eye balled the lines and at a glance they seem ok.
2 - Is o2 sensor giving bad readings causing the ECU to dump tons of fuel to where the exhaust manifold is leaking fuel onto the ground. I have an innovate wideband feeding an old Adaptronic PnP but I don't think this is the issue. Non-the-less I'll recalibrate the o2 sensor since its an easy thing.
3 - Pull off the manifold and inspect the fuel rail for leaks at the fuel line connections and also around the injectors themselves.
4 - If still no issue found, maybe the Fuel Pressure Regulator is bad? Any tips on how to test it rather than just purchasing a new one? I have a pressure gauge on it and the PSI is where I set it to once the fuel pump primes.
5 - Maybe an injector is stuck open? What's the best method to test?
6 - Return fuel line clogged? Any ideas on an easy way to test?
Other ideas? This is not some small fuel leak so its got to be something big.
Last edited by DaveW; 04-18-20 at 10:02 AM. Reason: added clarification
04-18-20, 08:37 AM
#3
RX-7 Bad Ass
iTrader: (55)
Jumper the fuel pump test connector in the diagnostic box and turn the key on, that will run the fuel pump with the engine not running. Then go track down the leaks. Fuel leaks are usually really easy to find.
A stuck open injector typically won't run just a little rich, it will be fuel pouring out of the turbo manifold. Most likely there's a leak onto the top of the engine that's getting down into the engine around the injector seals or something.
Start with the external leaks first.
Dale
A stuck open injector typically won't run just a little rich, it will be fuel pouring out of the turbo manifold. Most likely there's a leak onto the top of the engine that's getting down into the engine around the injector seals or something.
Start with the external leaks first.
Dale
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camajo (04-18-20)
06-06-20, 03:39 PM
#6
Hoping for more input here.
I finally got back to this and when I jumped the diag for the fuel pump I could hear fuel pooling in the manifold after the fuel pump runs for 10 seconds or so.
Seems to be an injector stuck open.
I then checked the voltages on the injectors and injector 3, or the rear primary, is registering 0 volts with the ignition on while the others are in the 12 to 13 range according to my Adaptronic PnP ECU. I switched the primaries around to see what would happen and the same thing occurs. Injector 3 is still giving 0 volts while 1,2 and 4 give 12 to 13. My thought is that this clears the actual injectors of being the issue. I have the think this limits the problem to the wiring or ECU but I'm looking for input. My next thought is to check continuity between the injector's plug and the ECU connector.
Any other thoughts?
I finally got back to this and when I jumped the diag for the fuel pump I could hear fuel pooling in the manifold after the fuel pump runs for 10 seconds or so.
Seems to be an injector stuck open.
I then checked the voltages on the injectors and injector 3, or the rear primary, is registering 0 volts with the ignition on while the others are in the 12 to 13 range according to my Adaptronic PnP ECU. I switched the primaries around to see what would happen and the same thing occurs. Injector 3 is still giving 0 volts while 1,2 and 4 give 12 to 13. My thought is that this clears the actual injectors of being the issue. I have the think this limits the problem to the wiring or ECU but I'm looking for input. My next thought is to check continuity between the injector's plug and the ECU connector.
Any other thoughts?
06-06-20, 06:16 PM
#7
After tinkering with things on and off today all four injectors are giving a good voltage. Bad thing is I don't know why! I hate electrical issues! Both of the injectors ohm'd out the same when out of the car so again it seems like the injectors are OK. My wiring harness has no splicing etc so its tough to say where along injector 3's path the bad connection occurs. UGH!
Hoping for more input here.
I finally got back to this and when I jumped the diag for the fuel pump I could hear fuel pooling in the manifold after the fuel pump runs for 10 seconds or so.
Seems to be an injector stuck open.
I then checked the voltages on the injectors and injector 3, or the rear primary, is registering 0 volts with the ignition on while the others are in the 12 to 13 range according to my Adaptronic PnP ECU. I switched the primaries around to see what would happen and the same thing occurs. Injector 3 is still giving 0 volts while 1,2 and 4 give 12 to 13. My thought is that this clears the actual injectors of being the issue. I have the think this limits the problem to the wiring or ECU but I'm looking for input. My next thought is to check continuity between the injector's plug and the ECU connector.
Any other thoughts?
I finally got back to this and when I jumped the diag for the fuel pump I could hear fuel pooling in the manifold after the fuel pump runs for 10 seconds or so.
Seems to be an injector stuck open.
I then checked the voltages on the injectors and injector 3, or the rear primary, is registering 0 volts with the ignition on while the others are in the 12 to 13 range according to my Adaptronic PnP ECU. I switched the primaries around to see what would happen and the same thing occurs. Injector 3 is still giving 0 volts while 1,2 and 4 give 12 to 13. My thought is that this clears the actual injectors of being the issue. I have the think this limits the problem to the wiring or ECU but I'm looking for input. My next thought is to check continuity between the injector's plug and the ECU connector.
Any other thoughts?
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