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try a continuity test on the -ve line of the injectors to the earth/chassis - if that happens with the ECU off then you have a wiring issue

^^^ yep or even a simple noid light on the inj plugs to see if they are constanty on

Ok both test were done and everything checked out perfectly. Even disconnected the fuel rail from the plenum and cranked the car with everything wired up all the injectors pulsed and none stayed open or shut.

Now continued my test and think I have found the problem. Remember I told you pressure in the fuel rail didn't even slowly dissipate, it went from priming at 40 psi to no pressure as soon as the pump stopped. Well that is the problem, somehow the fuel is getting into cylinder number 5. After I had checked the injectors I noticed that when cranking the car fuel gushed out of 5 and that was impossible as the fuel rail was out and I had not touched the car in a few days, thinking it could have been left in there I finished rolling the car over with the fuel pump disconnected to let the excess out. Now the cylinder was dry I even cranked it a few times to make sure,..... no fuel coming from the cylinder.

I then replaced the fuel pump fuse primed the line a few times and cranked the car...................... bingo!!!!!!!!!!!!! all kinds of fuel gushed out of number 5 and only number 5. So I removed the fuse and proceeded to force the fuel out through cranking the car all the fuel came out and the cylinder was cleared. Replaced the fuse primed it again and just as before cylinder 5 filled with gas. Now the problem has been found hooooooooooorrrrrrrrraaaaaaaaaaaaaaaaaayyyyyyyyyyyyyyyyyyy!!!!!!!!!!!!!!!!!!

Now the difficult part,.................... What the hell is wrong and how do I fix it?

Edited by Daboss
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If no. 5 is filling up with fuel then no. 5 injector must be stuffed or shorting completely open, somethign with the wiring or the actual injector is leaking

No it isn't I had the fuel rail completely removed, only thing I did was prime the fuel pump with the rail REMOVED and no. 5 filled with gasoline. Got all the gas out by cranking it with fuel pump disabled and rail not connected to plenum. When that was done replaced fuel pump fuse so that pump can prime again fuel rail still removed and no. 5 filled with gas again. Removed fuel pump fuse cranked car so that excess gas is removed from no.5, after no more gas came out the cylinder cranked car a few more times with no gas coming out that or any cylinder. Replaced fuse Primed fuel pump again with no fuel rail attached and after I had primed it a few times cranked it and fuel came gushing out of no.5 again still no fuel rail attached.

Hold on so you have removed the entire fuel rail and injector setup but fuel is still getting into number 5. I am completely confused, the injector setup and fuel rail is a closed circuit, all fuel must go out the return line, there is nothing else that holds fuel so how is it possible for fuel to get into the cylinders?

You sure it isn't coolant getting into the system from say a blown headgasket?

Hold on so you have removed the entire fuel rail and injector setup but fuel is still getting into number 5. I am completely confused, the injector setup and fuel rail is a closed circuit, all fuel must go out the return line, there is nothing else that holds fuel so how is it possible for fuel to get into the cylinders?

You sure it isn't coolant getting into the system from say a blown headgasket?

Yea I have completely removed the fuel rail,injectors and fuel is still getting into the the cylinder. Positive it isn't coolant, liquid is clear and smells like gas plus coolant has not moved a millimeter since the idling of the car and still has not now during the troubleshooting stages.

Exactly my point that's why I did it over so many times to make sure that's what was happening. I thought the only way for fuel to get in the cylinder would be through the fuel rail as well, but somehow when priming the fuel rail the fuel escapes into cylinder 5 and it is only number 5 cause that's the only cylinder that gushes fuel after priming. Think you are confused I am stumped, have no idea whats going on anyone with any kind of explanation throw it out there and I will try to test it out.

Edited by Daboss

tank -> Fuel pump -> fuel line > filter > fuel rail > fuel reg > return fuel line > tank

Now if you have removed the fuel rail and injectors from the motor, there is no long longer ANY path for fuel to get into the motor yes? So if there is 'fuel' in the motor it was either always there, or it is not actually fuel.

The ONLY way for fuel to get into the motor is via the injector ports in the intake, if the injectors aren't there and there isn't a leaking return line or reg some how gushing fuel into the holes then there is no path for fuel to get into the motor.

Edited by Rolls

When you say "have completely removed the fuel rail,injectors" does that mean you have take it completely off the car?

This may sound silly but, Did you block or re-route the fuel return and inlet lines? the fuel line joint to the rail is right above cylinder 5..

tank -> Fuel pump -> fuel line > filter > fuel rail > fuel reg > return fuel line > tank

Now if you have removed the fuel rail and injectors from the motor, there is no long longer ANY path for fuel to get into the motor yes? So if there is 'fuel' in the motor it was either always there, or it is not actually fuel.

The ONLY way for fuel to get into the motor is via the injector ports in the intake, if the injectors aren't there and there isn't a leaking return line or reg some how gushing fuel into the holes then there is no path for fuel to get into the motor.

I understand that that s why I removed fuel pump and cranked the engine with the fuel rail removed and no fuel comes from any cylinders. As soon as fuel pump is connected and primed a few times, still no fuel rail connected, and engine cranked fuel gushes from number 5.

When you say "have completely removed the fuel rail,injectors" does that mean you have take it completely off the car?

This may sound silly but, Did you block or re-route the fuel return and inlet lines? the fuel line joint to the rail is right above cylinder 5..

When I say remove I mean the fuel rail is disconnected from the plenum and moved by the throttle body with the injectors facing out the bonnet. No lines have been blocked, only reroute is to a fuel pressure regulator I have an aftermarket greddy copy plenum with and aftermarket fuel pressure regulator. It is setup like this: after coming from the filter it goes to the fuel rail, exits where the stock regulator use to be, have an adapter there that has a fuel line connected to the side of the regulator and then a fuel line from the bottom of the regulator to the return line.

Draw the setup, as if you have truley removed ti all there is absolutely no way for the fuel to get into the cylinders, it sounds like something isn't connected properly and is leaking fuel into the injector port.

Damn!!!!!!!!!!!!!!!!!!!!!!!! Thought I found the problem, removed the vacuum line from the fuel pressure regulator and fuel gushed out, was so happy cause I figured the regulator was the prob.

Figured the diaphragm was gone so it allowed fuel to go through it and come out of number five as that is the problem cylinder and the vacuum line is right in front of it. So I changed the regulator to another one I had lying around, got that installed and when priming the pump noticed that the pressure still would fall right off. Anyway thought nothing of it and started the car it bubbled like it was gonna start and then nothing, cranked it a few times and still nothing. Removed the vacuum line from the regulator and would you believe it fuel came from there as well. So decided to leave vac line unplug, clear cylinders and try again, still no luck and numbers 4,5 & 6 spark plugs always end up soaked while 1,2 & 6 are relatively dry.

No fuel came from the vacuum line of the newly installed regulator when priming the pump so it guess it is good, but car will not start and fuel seems to still be getting into 5 lots of fuel is in the turbo exhaust as well. Will check tomorro if it gets there from cranking or just an effect of fuel being pushed from cylinder 5 when I am clearing it.

Again my efforts have failed really thought I had it this time.. Battery died so had to cut test short will continue with compression test tomorro and also prime and crank car with the regulator vacuum line disconnected as well as fuel injectors and see if fuel still gets to any injectors.

Fuel pressure reg has a split diaphram, fuel pressure is going into the manifold through the vacuum hose

What do i win

Damn, should have read the last post

Ohhh so close!!!!!!!!!!!!!!

Hey you might still be right as I said fuel came from the top of that regulator as well, only test I did was prime it with the line off and then tried to suck it with my own breath. I just might not have enough lung power to force it open. Will continue test today and update.

The only other possible source is thru the charcoal canister which allows the excess vapour from the gas tank to be sucked in and burnt by the engine....

Long shot but have a look

That is no longer in the system. Took it out awhile back.

Update!!!!!!!!!!

Ok so I did a comp test wet and dry and these are the results. Dry 150 across all cylinders and wet 170 across number 5 as that seemed to be the problematic cylinder. Done on a cold engine and pistons are forged as well as a slightly thicker headgasket I think 1.3mm triple layer. Only did the wet test on cylinder 5 as was losing light and wanted to take the head down.

Took the head off and on the exhaust side looking through the exhaust ports all valves were wet with gas except number 6 and 4. These two were coated in carbon, but not wet. Number 5 was soaked on the side that meets the block and on the port side I would say number 1 was the worst. All wet up inside. What do you guys think? Running the car rich somehow stopped these valves from sealing properly therefore, the reason the car wasn't starting was that it could only run on two cylinders as only number 4 and 6 were ok?

Edited by Daboss

but you just said the compression test returned 150psi across all cylinders? which means the valves are sealing???

why did you take the head off if you have good compression?

I don't get why you took the head off either, it was clearly a fuel issue with the fuel reg leaking or a vac hose letting fuel into the motor some how.

Cause I changed the regulator and cleared as much of the fuel out the system as I could yet still could not get the car to start. With stock computer or pfc. So I figured this was my next step. It would still only bubble as if about to start but, no luck. Inspecting the exhaust ports noticed that all the exhaust valves were soaked except 6 and 4. Thats the only other step left to take. I figured they should not have been that wet as the injectors are good and they do not push that much fuel. I still can't figure out why the pressure just drops, it doesn't slowly come down it instantly falls to zero.

Edited by Daboss

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