Horrible knocking, high rpm and lack of boost (td5)

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I checked the fuel filter and fixed the leak by getting rid of the sensor and just screwing the plastic cap in its place. The fuel pump is still loud, so i think it's leaves me with three options:
fuel filter non return valve
fuel filter head bleed valve (edit: i can check it by simply blowing through it, am i correct?)
injector seals - i think this one is the most likely since the engine lacks power
fuel pump has done maybe 3000kms, so i don't think it's the problem, but i'm not sure - when I replaced it i was quiet for maybe 2 days, and then it got loud again, but it didnt affect the power in any way
 
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You said earlier that the oil is not rising so I very much doubt you have an issue with the injector seals. The only diesel pump that lasts is either genuine or Siemens VDO. Don't bother with the cheap ones as they will give trouble as soon as you install them.
 
NPG said:
You said earlier that the oil is not rising so I very much doubt you have an issue with the injector seals. The only diesel pump that lasts is either genuine or Siemens VDO. Don't bother with the cheap ones as they will give trouble as soon as you install them.
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The one i have is from Intermotor or something like that, i wanted to buy VDO, but it was unavailable and i didn't have time to wait for it. So maybe that's why it's loud, now i just have figure out why it's so painfuly slow when there is any degree of inclination. I will try disconnecting sensors tomorrow.
 
Agree with the comments on the fuel pump. If you have a sealed system and are confident that air is not getting in, then the only reason for a noisy pump is a failing pump. Lack of performance could be due to poor fueling, but it could also be a lack of boost. Have you checked MAF output to see if the turbo is working well and compared it against MAP output to ensure the boost is getting to the engine? On full throttle up a steep hill you should see about 650 or so from the MAF and 230+ from the MAP.
 
The only place that i can think of that could let air in to the system would be the injector seals or o-rings, everything else looks fine and most of it is new. The fuel pump is noisy, but i'm 99% sure, that it's not the problem behind the lack of power, the old one was also noisy, and car was driving like a dream (edit: for two years!). It has lost it's power when i was in the middle of my trip, i bypassed the wastegate modulator and got the power back for one day, but when i started it the next day, the problem appeared again. Putting brand new fuel pump changed nothing, i think that even bad quality fuel pump would fix the problem for at least a day if it was caused by the fuel pump.
I don't have the equipment to check the readings and it's too expansive for me at the moment, so i hope messing with the sensors today will give me some results. wish me luck!!
 
There are some simple things you can do without sensors.
First you can check for bearing wear on the turbo. Remove the air inlet pipe to the turbo and you will see the spindle. With the engine cold use your forefinger and thumb to gently check for wear left and right and in and out, some minor play is normal on an well used turbo, but it should not be more than about a mm. It should rotate freely without touching the sides. Check for witness marks on the blades and the inlet itself for any touching.
Next check that you are not losing boost. Check all of the hoses from the turbo through the intercooler to the inlet manifold. If possible remove them, check for splits and internal collapse and if OK put them back on. Make sure the jubilee clips (or better Mikalor clamps) are solid and not allowing any leaks.
Finally establish a performance baseline - there is a steep hill near where I live long enough that at max throttle the truck can achieve a final maximum speed. Find out what she will do now then disconnect the MAF and see if you get any more speed. Not a comprehensive or particularly scientific test, but is does give reproducible and therefore comparable results.
 
Already checked the turbo, intercooler and all the pipes and clips, everything in suprisingly good shape.
Thanks for the tip with the test, I even have a nice hill not far from where I live
 
Problem solved!!
I disconnected the MAF and AAP sensor, and the car got most of its power back, I forgot how nice it drives!
It's not the best the engine can do, but replacing the sensors should fix that, am i right?
Thank you again for help!
 
Maciej said:
Problem solved!!
I disconnected the MAF and AAP sensor, and the car got most of its power back, I forgot how nice it drives!
It's not the best the engine can do, but replacing the sensors should fix that, am i right?
Thank you again for help!
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Glad to hear you are getting somewhere! Funny how a modern vehicle runs better without the electrical sh1t attached yet the brains in the car behind the electrical sh1t cannot be asred to TELL you that the sensor sh1t is up the creek.
What were the car designers doing? I mean, if they want to treat us like children why do they not simply go the whole hog and have symbols with thumbs up for "ok to drive" or if not, symbols with a mechanic sucking his teeth and the words "This is going to cost yer" flashing across the dash? and then not allow anything at all to happen?
These vehicles are supposed to be capable of being driven across deserts, through swamps and the Australian outback. Only with a mobile garage following you it appears.
So glad you've found the fault(s).
 
Maciej said:
Problem solved!!
I disconnected the MAF and AAP sensor, and the car got most of its power back, I forgot how nice it drives!
It's not the best the engine can do, but replacing the sensors should fix that, am i right?
Thank you again for help!
Click to expand...

While I'm very happy for you, I fail to see how these 2 sensors have anything to do with a noisy fuel pump.

@Stanleysteamer - IMHO, the TD5 has the right balance of electronics - everything is there for a real purpose and they are extremely reliable when genuine or OEM parts are used. An OBD tool would have given the OP immediate indication that these 2 sensors are not functioning properly, if that's what the problem is.
 
NPG said:
While I'm very happy for you, I fail to see how these 2 sensors have anything to do with a noisy fuel pump.

@Stanleysteamer - IMHO, the TD5 has the right balance of electronics - everything is there for a real purpose and they are extremely reliable when genuine or OEM parts are used. An OBD tool would have given the OP immediate indication that these 2 sensors are not functioning properly, if that's what the problem is.
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In my opinion, if you are going to have a car that reads all sort of electrical stuff then a diagnostic screen should be built into the dash and connected at all times. How it works and what the codes mean should be in the driver's handbook. It should be part of the info given to the driver. Before electrics decent cars had gauges of all sorts that gave you as much info as you used to be able to get, oil pressure, temperatures of oil and water, ammeters or voltmeters. The driver was INFORMED, nowadays, there is so much the driver could be informed of but it is kept secret from him/her, unless he forks out the dosh for the diagnostic and plugs it in. WHY? Are we all so dumb? The simple answer is, expense, plus the fact that the average Joe or Joan just wants to get in, start it, drive off and chat to everyone while the car does the driving. Calling the AA when it stops working. Sadly this is happening in planes nowadays and they are falling out of the sky despite being flown by pilots who are supposedly properly taught. At least in a car you are unlikely to kill 300 odd people when the pitot head gets blocked with ice! (oops, don't have one, OK "speedo stops working")
 
NPG said:
While I'm very happy for you, I fail to see how these 2 sensors have anything to do with a noisy fuel pump.
Click to expand...
The sensors where causing lack of power, the fuel pump is still noisy but at this point I think i will ignore it since that's the only problem.

The obd tool my friend had only said that the ambient air pressure had some problems, but to be honest, i have no idea what this sensor does
 
Maciej said:
The sensors where causing lack of power, the fuel pump is still noisy but at this point I think i will ignore it since that's the only problem.

The obd tool my friend had only said that the ambient air pressure had some problems, but to be honest, i have no idea what this sensor does
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Ordinary OBD2 readers don't work with D2. only specialist readers work, search for this to find one for you but I use a Foxwell Scantool 520 and so far it does the biz for a fair price.SHOULD COME WITH THE VEHICLE FROM THE DAY IT IS MANUFACTURED!!!!!
 
Stanleysteamer said:
Ordinary OBD2 readers don't work with D2. only specialist readers work, search for this to find one for you but I use a Foxwell Scantool 520 and so far it does the biz for a fair price.SHOULD COME WITH THE VEHICLE FROM THE DAY IT IS MANUFACTURED!!!!!
Click to expand...

Yeah, the one he had worked well, it just didn't show any faults with the MAP, i think the sensor was giving some readings, so computer was thinking it is working properly, but the reading must have been wrong or something
 
Maciej said:
Yeah, the one he had worked well, it just didn't show any faults with the MAP, i think the sensor was giving some readings, so computer was thinking it is working properly, but the reading must have been wrong or something
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The TD5 does not normally register hard faults on these sensors - it describes the symptoms such as "Low Airflow" but that is not necessarily a fault with the MAF sensor. You need to take live readings and determine if they fall within an acceptable range. For MAF, you should be looking at around 60 when idle and going up to 600+ at 3000rpm and above. AFAIK, the AAP should give you a reading of around 101kPa, the actual atmospheric pressure at sea level.

Get yourself a copy of RAVE (look in this forum for web links) if you want to learn more on the function of each sensor and keep an eye on the oil level just in case you are right on the injector seals.
 
NPG said:
The TD5 does not normally register hard faults on these sensors - it describes the symptoms such as "Low Airflow" but that is not necessarily a fault with the MAF sensor. You need to take live readings and determine if they fall within an acceptable range. For MAF, you should be looking at around 60 when idle and going up to 600+ at 3000rpm and above. AFAIK, the AAP should give you a reading of around 101kPa, the actual atmospheric pressure at sea level.

Get yourself a copy of RAVE (look in this forum for web links) if you want to learn more on the function of each sensor and keep an eye on the oil level just in case you are right on the injector seals.
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Thank you for clarifying!
I'll start looking for the RAVE, and i don't really trust any seal on this car, so i check the oil daily
 
Stanleysteamer said:
In my opinion, if you are going to have a car that reads all sort of electrical stuff then a diagnostic screen should be built into the dash and connected at all times. How it works and what the codes mean should be in the driver's handbook. It should be part of the info given to the driver. Before electrics decent cars had gauges of all sorts that gave you as much info as you used to be able to get, oil pressure, temperatures of oil and water, ammeters or voltmeters. The driver was INFORMED, nowadays, there is so much the driver could be informed of but it is kept secret from him/her, unless he forks out the dosh for the diagnostic and plugs it in. WHY? Are we all so dumb? The simple answer is, expense, plus the fact that the average Joe or Joan just wants to get in, start it, drive off and chat to everyone while the car does the driving. Calling the AA when it stops working. Sadly this is happening in planes nowadays and they are falling out of the sky despite being flown by pilots who are supposedly properly taught. At least in a car you are unlikely to kill 300 odd people when the pitot head gets blocked with ice! (oops, don't have one, OK "speedo stops working")
Click to expand...

I'm afraid one cannot be anachronistic about these things - I'm sure those who were used to horse drawn carriages had the same sentiments when people started to use cars. I do agree that too much automation can be dangerous and will eventually lead to a society that doesn't need to think. But we have to admit that electronically controlled engines behave and perform way better than the older ones and many a times, the source of the trouble is some mechanical component. Most car owners don't even bother to open the bonnet so what's the point in giving them a cockpit when all they need is a steering wheel, 2 pedals and a sizeable overdraft.
 
NPG said:
I'm afraid one cannot be anachronistic about these things - I'm sure those who were used to horse drawn carriages had the same sentiments when people started to use cars. I do agree that too much automation can be dangerous and will eventually lead to a society that doesn't need to think. But we have to admit that electronically controlled engines behave and perform way better than the older ones and many a times, the source of the trouble is some mechanical component. Most car owners don't even bother to open the bonnet so what's the point in giving them a cockpit when all they need is a steering wheel, 2 pedals and a sizeable overdraft.
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I get your point and do agree that electonically controlled engines, when they work, are better. but ACE, HDC, TC, electronic gearboxes, etc etc, are often more trouble than they are worth. KISS. "Keep It Simple, Stupid" should be carved into the desks of all designers!
 
Stanleysteamer said:
What were the car designers doing? I mean, if they want to treat us like children why do they not simply go the whole hog and have symbols with thumbs up for "ok to drive" or if not, symbols with a mechanic sucking his teeth and the words "This is going to cost yer" flashing across the dash? and then not allow anything at all to happen?
Click to expand...

Admit it. You work for Tesla.

I too think the TD5 is just about at the right balance. The electronics are useful and are pretty robust and reliable, but are very basic by modern standards and so can be worked on and around by the DIY mechanic, as long as they have access to the knowledge of the gurus on here. If I was crossing the Empty Quarter I would probably prefer a 300Tdi, but for European travel, I think the TD5 is a great balance. Of the other stuff - I like TC, ABS and HDC, they add a great deal of safety and capability, but I made sure my cab has CDL as well. They can be troublesome, it is true, but failure in the field should not leave you stranded and they are MOT-essential. SLS and ACE are nice to have, the truck handles better, tows better, rides better and is probably better off road. But for overlanding they are an unnecessary complication that could potentially leave you stranded. As they are not required for the MOT, my truck has had them removed, and I don't miss them at all.
 
This may be irrelevant but the amount of Land Rover owners I know who don’t even own a grease gun is quite amusing really
 
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