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T
terrance
Guest
Thanks for the reply. Not Sure. What does it do? The guy said something about relacing a pressure cap when they checked inside the tank not sure where abouts this is or what its purpose is?
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very strange indeed!
Firstly I dont think its air in the fuel filter you said that you open the drain tap on the bottom of the filter and air came out. if air did come out your whole fuel filter must be empty and you wouldn't get the engine started.
There are a couple of things it could be
1. There is a problem with a fuel line and not enough fuel is getting to the fuel pump this would cause a negative pressure inside the fuel filter housing and when you undo the tap at the bottom air is being sucked in.
As you have had your fuel lines and tank checked it could be something like a faulty rubber hose that is kinked or I have had it where the rubber pipe has been pushed onto a metal one and its cut a slice of hose inside that has acted like a flap and can sometimes block the pipe but once you release the pressure by undoing the tap the flap returns and lets fuel flow again.
2. It could be a problem inside your fuel pump with the fuel pressure regulator
3. It could be something totally unrelated to the fuel system like a intermitant air flow sensor problem, A faulty throttle switch, A faulty earth point or a sensor fault
Has the engine management light ever come on?
Does the engine managment light come on when you switch the ignition on? if it doesn't you could have a blown bulb and there could be a stored fault in the ecu
Firstly I dont think its air in the fuel filter you said that you open the drain tap on the bottom of the filter and air came out. if air did come out your whole fuel filter must be empty and you wouldn't get the engine started.
There are a couple of things it could be
1. There is a problem with a fuel line and not enough fuel is getting to the fuel pump this would cause a negative pressure inside the fuel filter housing and when you undo the tap at the bottom air is being sucked in.
As you have had your fuel lines and tank checked it could be something like a faulty rubber hose that is kinked or I have had it where the rubber pipe has been pushed onto a metal one and its cut a slice of hose inside that has acted like a flap and can sometimes block the pipe but once you release the pressure by undoing the tap the flap returns and lets fuel flow again.
2. It could be a problem inside your fuel pump with the fuel pressure regulator
3. It could be something totally unrelated to the fuel system like a intermitant air flow sensor problem, A faulty throttle switch, A faulty earth point or a sensor fault
Has the engine management light ever come on?
Does the engine managment light come on when you switch the ignition on? if it doesn't you could have a blown bulb and there could be a stored fault in the ecu
Toolbox
Well-known member
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- 1,929
terrance said:
When fuel is used from the tank the space in the tank that was subsequently taken up by the fuel has to be replaced with air, normally there is a valve in the filler cap that lets air in to the tank. If no air can get in to the tank there becomes a vacuum in the tank that will pull the fuel back from the engine resulting in similar problems to yours. The Terrano is more susceptible to this as it has no external fuel lift pump supplying the injection pump, the injection pump in this case draws its own fuel from the tank.
Have all the fuel lines been checked even the return line?
T
terrance
Guest
Thanks for the interesting replies. In answer to both of your questions, the fuel lines have all been checked twice. I've even had a look myself (not that i know what im looking at) but they all seem to be in good condition.
The engine managment light has never come on and it does work when u turn on the ignition - I just checked!!! :roll:
The car has run fine all weekend so im wondering if this pressure cap thing that got replaced has fixed it not sure where or what this does!
The engine managment light has never come on and it does work when u turn on the ignition - I just checked!!! :roll:
The car has run fine all weekend so im wondering if this pressure cap thing that got replaced has fixed it not sure where or what this does!
T
terrance
Guest
update: Dare i speak to soon but ive driven around all week now, even towed my horse trailer and so far so good! think i will phone garage on monday to find out what this pressure cap thing was as im intrested to know its purpose. thanks again for all the replies. :smile:
T
terrance
Guest
Problem happened again yesterday! after three weeks with no problem very strange. happened as i accelarated hard up a hill to overtake a granny! very embarrasing! 
replaced the filler cap today to see if it makes any diffrence!
replaced the filler cap today to see if it makes any diffrence!
G
Guest
Guest
hi all, well you will be pleased to know that i had the same problem or one that sounds very very similar.
quick question???
if you start it up and leave it ticking over for a while then go to pull away does it die on you?
i found air in my filter,primed it,off i go afew miles,lose power,air in filter,prime and so on.
drained tank completley
change filter
nice clean fuel
presto...no problems
i did find a really horrible black sludge in filter and diesel was black and very thin from tank....almost as if petrol had been added.......
hope this is of some help,it might not be the same and i cant promise it will cure yours,as they say,
its only a suggestion
chris66
quick question???
if you start it up and leave it ticking over for a while then go to pull away does it die on you?
i found air in my filter,primed it,off i go afew miles,lose power,air in filter,prime and so on.
drained tank completley
change filter
nice clean fuel
presto...no problems
i did find a really horrible black sludge in filter and diesel was black and very thin from tank....almost as if petrol had been added.......
hope this is of some help,it might not be the same and i cant promise it will cure yours,as they say,
its only a suggestion
chris66
T
terrance
Guest
hi again,
After replacing the filler cap i thought the problem had been solved! the car drove perfectly for two months even towing untill last week when once again dirving uphill in 4th gear i lost power untill i let air in/out? of fuel filter housing and away we went fine for a week and then the same thing happened today i have no idea what to do next this is a big mystery!! any advice appreciated guys
After replacing the filler cap i thought the problem had been solved! the car drove perfectly for two months even towing untill last week when once again dirving uphill in 4th gear i lost power untill i let air in/out? of fuel filter housing and away we went fine for a week and then the same thing happened today i have no idea what to do next this is a big mystery!! any advice appreciated guys
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Just a thought, could it be the actual primer pump on the filter letting air in, I've never stripped one down, but if they are designed to let air out, if faulty or a bit of grit in the valve, hole in diaphragm etc could let air in.terrance said:hi again,
After replacing the filler cap i thought the problem had been solved! the car drove perfectly for two months even towing untill last week when once again dirving uphill in 4th gear i lost power untill i let air in/out? of fuel filter housing and away we went fine for a week and then the same thing happened today i have no idea what to do next this is a big mystery!! any advice appreciated guys
Well you are grasping at straws... but at least you know how to sort it out at the side of the road.
Oh just looked back in the threads and you said you had checked it.. may be worth looking at again, for letting air back in..
T
terrance
Guest
hi everyone!
After 6 months of this problem i now think i have solved the problem ( dare i say this :roll: ) after getting more and more frequent i tired driving today with the filler cap not done up properly and i had super power again i tested this several times up a step fast road which has not been possible for several months!!! my question is if i had a new filler cap which worked for a few weeks, what happened? why is it not regulating the air pressure in tank? did i get the wrong cap? even though i ordered the part from nissan? what do your filler caps look like? when u open the cap do u hear a rush of air?
Any input appreciated, for the time being i am driving with the cap not completely done up.
After 6 months of this problem i now think i have solved the problem ( dare i say this :roll: ) after getting more and more frequent i tired driving today with the filler cap not done up properly and i had super power again i tested this several times up a step fast road which has not been possible for several months!!! my question is if i had a new filler cap which worked for a few weeks, what happened? why is it not regulating the air pressure in tank? did i get the wrong cap? even though i ordered the part from nissan? what do your filler caps look like? when u open the cap do u hear a rush of air?
Any input appreciated, for the time being i am driving with the cap not completely done up.
Deleted Member S
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I sometimes hear a rush of air when I remove mine :? :?
Do these tanks have a breather pipe from them :?: The reason I ask is I wonder if it's getting bunged up :?
Do these tanks have a breather pipe from them :?: The reason I ask is I wonder if it's getting bunged up :?
T
terrance
Guest
No idea! if they do how would i get it unbunged? :?
T
terrance
Guest
Im still wondering if i have the correct filler cap it is black with a white diaphram piece inside?
T
terrance
Guest
The Mystery begins ot unfold!!
Im finally coming to a conclusion on this problem which is now so bad u cannot drive the car without disconecting the maff, and no its not the maff because ive put a new one on.
Had a guy out today to yet again do diagnostics and horay finally a fault code apeared. turbo pressure, we looked at the pipe going into the turbo and sure enough there was a split also after removing pipe some fuel came out! the guy recons the boost pressure valve and seal have gone hense the lack of power problem.
Will keep u posted once this has been replaced.
Im finally coming to a conclusion on this problem which is now so bad u cannot drive the car without disconecting the maff, and no its not the maff because ive put a new one on.
Had a guy out today to yet again do diagnostics and horay finally a fault code apeared. turbo pressure, we looked at the pipe going into the turbo and sure enough there was a split also after removing pipe some fuel came out! the guy recons the boost pressure valve and seal have gone hense the lack of power problem.
Will keep u posted once this has been replaced.
T
terrance
Guest
Ok an Update.
Have been trying to replace this boost pressure valve and after lots of hunting have come to the conclusion with nissan that this part comes as part of the turbo and is not sold seperatly. Really frustrationg because i think the turbo itself is actually working. this part looks like a round metal thing at the side of turbo (it has a number on it) and has two bolts attaching it, at bottom is a small rubber tube attached with clips (which had a split) going in to the big corsatina looking tube which goes to the maff. When u disconect the maff the car drives ( hope this makes sense :lol: )
Anyway truck going to the guy (the one that did the diagnostics and found a fault code) on mon to have this part stripped off to see if we can match this part up fingers crossed or i may be looking at a new turbo!! eek :x
Have been trying to replace this boost pressure valve and after lots of hunting have come to the conclusion with nissan that this part comes as part of the turbo and is not sold seperatly. Really frustrationg because i think the turbo itself is actually working. this part looks like a round metal thing at the side of turbo (it has a number on it) and has two bolts attaching it, at bottom is a small rubber tube attached with clips (which had a split) going in to the big corsatina looking tube which goes to the maff. When u disconect the maff the car drives ( hope this makes sense :lol: )
Anyway truck going to the guy (the one that did the diagnostics and found a fault code) on mon to have this part stripped off to see if we can match this part up fingers crossed or i may be looking at a new turbo!! eek :x
T
terrance
Guest
I have another question??
Could the fact that i have air coming out of the fuel filter pipe have anything to do with the turbo ??? there is still air comming out but this doesnt fix the problem anymore so im not even sure its related to the power loss thing?? so should i worry about it?? :roll:
Could the fact that i have air coming out of the fuel filter pipe have anything to do with the turbo ??? there is still air comming out but this doesnt fix the problem anymore so im not even sure its related to the power loss thing?? so should i worry about it?? :roll:
T
terrance
Guest
Hi again
Ok next update.
Managed to find a pressure valve for turbo unfortunatly this did not fix the problem. Now looks like im going to have to replace the turbo.
Where is the best place to get a turbo? Should i go for a reconditioned one or a new one? Nissan have quoted me £1369 including fitting and Vat.
Many thanks.
Ok next update.
Managed to find a pressure valve for turbo unfortunatly this did not fix the problem. Now looks like im going to have to replace the turbo.
Where is the best place to get a turbo? Should i go for a reconditioned one or a new one? Nissan have quoted me £1369 including fitting and Vat.
Many thanks.
Toolbox
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Terrance,
How did the chap diagnose the turbo pressure fault? as far as I am aware there is no pressure sensor for turbo boost in inlet manifold and shouldn’t have an error to go with it?
If the waist gate valve diaphragm had failed on the turbo it would have stayed closed keeping pressure in, unless the turbo is completely US, this you would be able to see.
How did the chap diagnose the turbo pressure fault? as far as I am aware there is no pressure sensor for turbo boost in inlet manifold and shouldn’t have an error to go with it?
If the waist gate valve diaphragm had failed on the turbo it would have stayed closed keeping pressure in, unless the turbo is completely US, this you would be able to see.
T
terrance
Guest
Thanks for the
reply
The guy had a machine that read codes from ecu he had a specific machine for japanese cars (the only person that seemed to know what they where talking about) anyhow hes main work is electrical fault finding so when the pressure valve thing didnt work he got another guy to check turbo today how took part of it off to test i believe? he said that the turbo was gone
I dont know what to believe anymore. what i dont understand is if the turbo is gone how come i can drive the car with the maff disconected? (slowly) :?
reply
The guy had a machine that read codes from ecu he had a specific machine for japanese cars (the only person that seemed to know what they where talking about) anyhow hes main work is electrical fault finding so when the pressure valve thing didnt work he got another guy to check turbo today how took part of it off to test i believe? he said that the turbo was gone
I dont know what to believe anymore. what i dont understand is if the turbo is gone how come i can drive the car with the maff disconected? (slowly) :?
