Seriously over Fuelling, Fuel Leaking Out From Underneath!
Discussion
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Hi guys, there is a link above of my previous post from Saturday regaring the hissy fit that my chim has thrown now. This has developed further now though from where it was. What started as a lumpy idle and a smell of fuel is now a pretty much non existant idle, when revved a massive amount of smoke from the exhaust and the stench of fuel is massive. I noticed that the fuel was dripping out from the exhaust manifold on the ns, which has a gasket gone and is on the list to be done at the mo anyway. But the fuel is literally dripping out of the bottom of the car, so obviously I turned it off pretty sharpish and pushed it into the garage.
Is there a way that an injector can get stuck open and just keep pouring fuel in? That's what it seems like, as if it is just chucking it in and obviously flooding it to death. It was totally fine for a long drive just before this, very strange.
The car is booked in for a 12k service at TVR Power in a couple of weeks, so if I can't sort this I will have to get it trailored there now!
Please somebody reply with a nice easy fix of "change a little sensor or something" I am cursing the thing at the minute - needless to say the grief I'm getting at work with the old unreliable TVR jokes is just awful haha!
Hi guys, there is a link above of my previous post from Saturday regaring the hissy fit that my chim has thrown now. This has developed further now though from where it was. What started as a lumpy idle and a smell of fuel is now a pretty much non existant idle, when revved a massive amount of smoke from the exhaust and the stench of fuel is massive. I noticed that the fuel was dripping out from the exhaust manifold on the ns, which has a gasket gone and is on the list to be done at the mo anyway. But the fuel is literally dripping out of the bottom of the car, so obviously I turned it off pretty sharpish and pushed it into the garage.
Is there a way that an injector can get stuck open and just keep pouring fuel in? That's what it seems like, as if it is just chucking it in and obviously flooding it to death. It was totally fine for a long drive just before this, very strange.
The car is booked in for a 12k service at TVR Power in a couple of weeks, so if I can't sort this I will have to get it trailored there now!
Please somebody reply with a nice easy fix of "change a little sensor or something" I am cursing the thing at the minute - needless to say the grief I'm getting at work with the old unreliable TVR jokes is just awful haha!
I cannot understand how enough petrol is pouring down a hot engine so that it is dripping underneath. I am interested in hearing what the more mechanically experienced Tivvers suggest.
I guess the key question is where is the drip underneath? This way you can possibly trace the leak back to it's source.
Have you double checked your fuel hoses to the fuel rail? Have you had the fuel rail out? Or the injector O rings leaking in the intake manifold? Is it firing on all cylinders?
I would be really careful about starting it up if the fuel leaking out is this bad. You don't want to end up in a ball of flames.
Have you tried resetting the ECU? I'm not sure if this would have any bearing on the control of the injectors.
I guess the key question is where is the drip underneath? This way you can possibly trace the leak back to it's source.
Have you double checked your fuel hoses to the fuel rail? Have you had the fuel rail out? Or the injector O rings leaking in the intake manifold? Is it firing on all cylinders?
I would be really careful about starting it up if the fuel leaking out is this bad. You don't want to end up in a ball of flames.
Have you tried resetting the ECU? I'm not sure if this would have any bearing on the control of the injectors.
As Chuffmeister has said, where exactly is the fuel coming out? If it is pouring off the back of the engine, then there is probably a fuel leak from a seal or pipe somewhere on the fuel rail.
I have also seen fuel coming out of the air filter before, when the plenum had been filled up by a failed fuel pressure regulator. It was a nasty Chinese pattern part, and the internal diaphragm had split. This allowed the fuel to come up the little vacuum line, and fill the plenum! Overall fuel pressure is raised in these circumstances too.
Before doing any checking, I would strongly recommend that you disconnect the ignition coil. You should also work outdoors, and have the correct fire extinguisher to hand!
In case the plenum has been filled up, this could also hydraulic-lock the engine. I would highly recommend that you actually call someone for advice before proceeding.
Good Luck!
I have also seen fuel coming out of the air filter before, when the plenum had been filled up by a failed fuel pressure regulator. It was a nasty Chinese pattern part, and the internal diaphragm had split. This allowed the fuel to come up the little vacuum line, and fill the plenum! Overall fuel pressure is raised in these circumstances too.
Before doing any checking, I would strongly recommend that you disconnect the ignition coil. You should also work outdoors, and have the correct fire extinguisher to hand!
In case the plenum has been filled up, this could also hydraulic-lock the engine. I would highly recommend that you actually call someone for advice before proceeding.
Good Luck!
Thanks for the replies guys - I don't think it's a fuel hose as the dripping is from the ns front around the exhaust manifold area, near the power steering pump. As for running on all cylinders, the last time I started it up it would ardly run at all so I just turned it off quick.
I do have the gasket gone on the ns manifold and it looks like to me that where it is flooding fuel in and obviously shoving loads of unburnt down the exhaust that is actually dripping out of the manifold at the front near the ps pump, I am assuming where the gasket is blown it's coming through there?
I have looked up around the injector area and can't see any signs of a leak up there, so that's why I had sort of made the conclusion that an or all of the injectors had stayed open and just kept pouring it in?
I have googled it loads and found various causes and posts etc but a lot of stuff about ecu faults or wiring faults.
How the hell do you diagnose this if it's in a position where you can't really start it up?
I do have the gasket gone on the ns manifold and it looks like to me that where it is flooding fuel in and obviously shoving loads of unburnt down the exhaust that is actually dripping out of the manifold at the front near the ps pump, I am assuming where the gasket is blown it's coming through there?
I have looked up around the injector area and can't see any signs of a leak up there, so that's why I had sort of made the conclusion that an or all of the injectors had stayed open and just kept pouring it in?
I have googled it loads and found various causes and posts etc but a lot of stuff about ecu faults or wiring faults.
How the hell do you diagnose this if it's in a position where you can't really start it up?
try disconecting the coil then disconnect an injector and stick an LED into plug and crank the engine over, it should flash, if on constant then your ECU is almost certainly faulty and holding the injectors open all the time.
Also worth hiring a fuel pressure gauge and seeing what the pressure is like at the fuel rail.
When you do get it running I would also change the oil, some petrol will have got past the rings and diluted it.
Good luck.
Also worth hiring a fuel pressure gauge and seeing what the pressure is like at the fuel rail.
When you do get it running I would also change the oil, some petrol will have got past the rings and diluted it.
Good luck.
If you have RoverGauge you can trigger the fuel pump (you an also probably do this with other diagnostic equipment. If necessary you could do this by manually triggering the fuel pump relay as well).
This would pressurise the fuel rail which may give some indication as to the source of the leak.
If you could get someone else to do this then they would be able to switch it off quicker if necessary.
The only thing that I can think of that might leak on the NS front apart from an injector is the fuel temperature sensor which is in the fuel rail at the front NS. It is near the engine temperature ECU sensor.
A system that I use to locate the source of leaks is to use something like kitchen roll and put this as flat as possible where you think the source of the leak is. If these is a leak it changes colour (blue paper is the best from experience) and consistency and stops the fluid from running so much so that it is easier to pinpoint the source. It also make cleaning up easier to check again quickly.
However I would strongly advise the previously mentioned precautions of outside and an extinguisher handy.
This would pressurise the fuel rail which may give some indication as to the source of the leak.
If you could get someone else to do this then they would be able to switch it off quicker if necessary.
The only thing that I can think of that might leak on the NS front apart from an injector is the fuel temperature sensor which is in the fuel rail at the front NS. It is near the engine temperature ECU sensor.
A system that I use to locate the source of leaks is to use something like kitchen roll and put this as flat as possible where you think the source of the leak is. If these is a leak it changes colour (blue paper is the best from experience) and consistency and stops the fluid from running so much so that it is easier to pinpoint the source. It also make cleaning up easier to check again quickly.
However I would strongly advise the previously mentioned precautions of outside and an extinguisher handy.
Just spoke to Jason at TVR Power where the car is booked in for it's 12k service in a couple of weeks, totally top guy and really helpfull.
He thinks it definately sounds like the injectors sticking on and suggested that there is a section of wiring loom at the back of the engine that they have seen rub through many times, which would cause the short to cause the injectors to stay open.
Made the decision that I am leaving it for them to sort out and am going to get it recovered into them as soon as I can.
He thinks it definately sounds like the injectors sticking on and suggested that there is a section of wiring loom at the back of the engine that they have seen rub through many times, which would cause the short to cause the injectors to stay open.
Made the decision that I am leaving it for them to sort out and am going to get it recovered into them as soon as I can.
mattgtd said:
Just spoke to Jason at TVR Power where the car is booked in for it's 12k service in a couple of weeks, totally top guy and really helpfull.
He thinks it definately sounds like the injectors sticking on and suggested that there is a section of wiring loom at the back of the engine that they have seen rub through many times, which would cause the short to cause the injectors to stay open.
Made the decision that I am leaving it for them to sort out and am going to get it recovered into them as soon as I can.
Keep us all posted as how Jason did the fix. Mark will be interested as well.He thinks it definately sounds like the injectors sticking on and suggested that there is a section of wiring loom at the back of the engine that they have seen rub through many times, which would cause the short to cause the injectors to stay open.
Made the decision that I am leaving it for them to sort out and am going to get it recovered into them as soon as I can.
Adrian@ said:
Did you get around to checking the dipstick for petrol in the oil...as I had said the other post...IMHO, very wise to get a man who can.
Adrian@
I haven't to be honest, but it's having the 12k service when it goes in to powers so it will all be done then anyway inc new plugs which I am assuming it will definately need now!Adrian@
[quote=mattgtd]Just spoke to Jason at TVR Power where the car is booked in for it's 12k service in a couple of weeks, totally top guy and really helpfull.
He thinks it definately sounds like the injectors sticking on and suggested that there is a section of wiring loom at the back of the engine that they have seen rub through many times, which would cause the short to cause the injectors to stay open.
Made the decision that I am leaving it for them to sort out and am going to get it recovered into them as soon as I can.[/quote
The injectors have a 12 volt feed on one side, and then are earthed on the other side by the ECU when the injectors are fired. If the wiring loom has failed you could do a resistance check to the ground side- it should be the yellow / blue and yellow / white wires to ground should be open circuit (or high resistance) to ground with the ignition off. If either side is near 0 ohms you have found the cause.
He thinks it definately sounds like the injectors sticking on and suggested that there is a section of wiring loom at the back of the engine that they have seen rub through many times, which would cause the short to cause the injectors to stay open.
Made the decision that I am leaving it for them to sort out and am going to get it recovered into them as soon as I can.[/quote
The injectors have a 12 volt feed on one side, and then are earthed on the other side by the ECU when the injectors are fired. If the wiring loom has failed you could do a resistance check to the ground side- it should be the yellow / blue and yellow / white wires to ground should be open circuit (or high resistance) to ground with the ignition off. If either side is near 0 ohms you have found the cause.
Update.... Paul (Rugbyfester on here) kindly popped over and plugged his ecu mate into the old girl and it threw up ecu temp sensor or wiring fault. We swapped the sensor and still the same. When I had spoke to Jason at Powers earlier the first thing he said was also wiring and more specificly he had seen some wiring chafe through before that had shorted the injector circuit or something and made them over fuel.
It basically seems like the ecu thinks it is too lean and so is chucking more fuel at it to richen it up and in turn is seriously flooding it in the process.
Looking at transportation companies now to get it to Jason and the boys.
It basically seems like the ecu thinks it is too lean and so is chucking more fuel at it to richen it up and in turn is seriously flooding it in the process.
Looking at transportation companies now to get it to Jason and the boys.
I'm a bit late to the party but I have seen this happen recently on a BMW, the cause was trapped /chafed wires which caused all the injectors to spray constantly, hydraulically locking the engine and doing a lot of damage.
IT sounds like your guy has his finger on the pulse, I would take out the plugs at least, don't smoke whilst you're doing it either.
IT sounds like your guy has his finger on the pulse, I would take out the plugs at least, don't smoke whilst you're doing it either.
kev b said:
I'm a bit late to the party but I have seen this happen recently on a BMW, the cause was trapped /chafed wires which caused all the injectors to spray constantly, hydraulically locking the engine and doing a lot of damage.
IT sounds like your guy has his finger on the pulse, I would take out the plugs at least, don't smoke whilst you're doing it either.
when you say hydraulically locking the engine and doing a lot of damage, did it happen to the beemer whilst it was on the move then?IT sounds like your guy has his finger on the pulse, I would take out the plugs at least, don't smoke whilst you're doing it either.
kev b said:
I'm a bit late to the party but I have seen this happen recently on a BMW, the cause was trapped /chafed wires which caused all the injectors to spray constantly, hydraulically locking the engine and doing a lot of damage.
IT sounds like your guy has his finger on the pulse, I would take out the plugs at least, don't smoke whilst you're doing it either.
when you say hydraulically locking the engine and doing a lot of damage, did it happen to the beemer whilst it was on the move then?IT sounds like your guy has his finger on the pulse, I would take out the plugs at least, don't smoke whilst you're doing it either.
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