FUEL PRESSURE TOO HIGH/TOO LOW: 2005 TDV6 Discovery 3 S

[Dreamn]

I recently had a new short motor installed into our 2005 Discovery 3 TDV6 as per http://www.aulro.com/afvb/d3-d4-rrs/153720-blown-head-gasket-2005-discovery-3-tdv6-s-4.html#post1711195 .

The problem now is that on test driving, the vehicle will get to around 95 to 100k with the foot planted but then dies and goes into limp mode. the error codes that are coming up are P0088 (Fuel rail/system pressure – too high) and P2290 (Injector control pressure too low). these codes to me appear to be a contradiction of each other but I'm by no means a mechanic.

A couple of things I should probably point out that may or may not assist with the diagnosis are:

1) The old motor was overheated (the reason for the new motor).

2) Replacement motor was a short motor i.e. we used the old fuel pump and injectors.

3) Prior to overheating the old motor the vehicle would often go into limp mode while towing the van up a steep long grade. after researching this forum it appears to be, from what I can tell, a relatively common problem resulting from temperamental computer communication with the gearbox. Note: this problem would also occur when planting the foot in soft sand for extended periods.

4) An EGR blanking plug was installed.

With that being said..none of the codes mentioned above have occurred until now.

Cheers
Steve

[Graeme]

Could the fuel filter be overdue for replacement?

[Dreamn]

Could the fuel filter be overdue for replacement?

Thanks Graeme, I had the fuel filter replaced around 4,000k ago hoping to solve the issue related to the limp mode on hills under load (didn't solve it). So it's probably unlikely to be the problem. As a side note, while I was with the mechanic today he had removed the fuel filter looking for brass that may indicated fuel pump damage resulting from the overheating but as far as I'm aware he didn't find any.

[sniegy]

High pressure fuel pump?

[Dreamn]

High pressure fuel pump?

This is where my mechanical naivety will be displayed. I was assuming that there was only the one fuel pump. When you say "high pressure fuel pump" are you distinguishing that from what I call "the" fuel pump?

I did a little research on your suggestion and came across this post by jonesy63 http://www.aulro.com/afvb/d3-d4-rrs/143118-tdv6-vs-v6-post1615639.html#post1615639 then found a recall for the same problem in the UK here http://www.warrantyguide.co.uk/vehicle-recall-61BBD89D3B3E8135802577A6003499E6-land-rover-discovery-3-tdv6-and-rang . Are these recalls world wide? i.e. would there have been an Australian recall also?

Cheers
Steve

Edit: The above links may not be related to my vehicle. The UK recall refers to Vehicles built from 1/1/2006 to 30/6/2009, mine is a MY05.

[CaverD3]

First filter/strainer in the tank could be gummed up?

[Dreamn]

First filter/strainer in the tank could be gummed up?

Thanks Caver
I can understand how this would possibly cause a problem with the injector control pressure being too low but would it also create the problem with the fuel rail/system pressure being too high?

Cheers, Steve

[BigJon]

This is where my mechanical naivety will be displayed. I was assuming that there was only the one fuel pump. When you say "high pressure fuel pump" are you distinguishing that from what I call "the" fuel pump?




There is an electric pump in the tank which supplies fuel to the belt driven mechanical pump on the back of the engine.

[Dreamn]

I hadn't even considered the fuel tank pump as a possibility as all the recent work had been done at the engine.

My mechanic informed me this morning that the car won't even start now. It appears that the high pressure fuel pump had been drawing from the tank without the assistance of the electric tank pump but after bleeding the fuel line while checking filters etc the high pressure pump is now unable to draw the fuel from the tank.

I'm guessing it's possible that the high pressure pump working overtime to draw and supply fuel could cause a fluctuation resulting in my current problem?

[CaverD3]

It would be a cheaper fix than the HP pump.

[Dreamn]

It would be a cheaper fix than the HP pump.

Yes but I was still surprised to find the tank pump priced around $1, 300, fortunately I sourced a second hand one with 12, 000km on it for just under $500. I'm hoping this will mark the end of my mechanical woes. Cape York beckons!

[CaverD3]

Ouch. :eek: Sometimes it is not the pump itself have a a look at the strainer for slime.

[Grappler]

Ive been monitoring the fuel rail pressure with an Ultragauge at about 12000 psi at 110 kph on a flat road
The specification says the pump can develop 24000 psi, so Im concerned something is not right even though the RRS runs beautifully. Filters are clean and no faults are logged when I scan the PCM
Does anyone have measurements of actual rail pressures reading for TDV6 2.7, I can compare?

[BradC]

Ive been monitoring the fuel rail pressure with an Ultragauge at about 12000 psi at 110 kph on a flat road
The specification says the pump can develop 24000 psi, so Im concerned something is not right even though the RRS runs beautifully. Filters are clean and no faults are logged when I scan the PCM
Does anyone have measurements of actual rail pressures reading for TDV6 2.7, I can compare?

Lock it in 3rd and go like hell nailed to the boards up a big hill. Then you'll see > 1600bar.

No faults? No worries. 110 on the flat isn't anywhere like a big enough load to get the pressure up.

[Eric SDV6SE]

Lock it in 3rd and go like hell nailed to the boards up a big hill. Then you'll see > 1600bar.

No faults? No worries. 110 on the flat isn't anywhere like a big enough load to get the pressure up.

"Officer: why were you speeding ?
Driver: just testing the high pressure fuel pump pressure in my landrover ....sir"

[DazzaTD5]

Ive been monitoring the fuel rail pressure with an Ultragauge at about 12000 psi at 110 kph on a flat road
The specification says the pump can develop 24000 psi, so Im concerned something is not right even though the RRS runs beautifully. Filters are clean and no faults are logged when I scan the PCM
Does anyone have measurements of actual rail pressures reading for TDV6 2.7, I can compare?

As already mentioned, no faults? then no issue. The pressure will vary depending on load and an engine that develops such huge amounts of torque its sometime hard to make it work hard enough.

Key point, change that fuel filter every 10K

[BradC]

"Officer: why were you speeding ?
Driver: just testing the high pressure fuel pump pressure in my landrover ....sir"

Yep, been there and done that. Greenmount hill has been my Italian tuneup drag since I started driving. I've always found being polite and not trying to bull**** (yes officer, I looked at the clock after I was alerted to your presence and indeed I was speeding. Sorry) resulted in a "take more care sir and have a nice day".

If you want to do it without speeding then you can flog it to 90 on the on-ramp from Alexander Drive to Reid Hwy West-bound. Nice steep hill and if you grab 3rd early enough you can get a good wind out before having to ease off at the top of the hill. I've seen indicated fuel pressures in excess of 1650 bar doing that. I've also done it with the van on the back to *really* blow the cobwebs out.

[Grappler]

Lock it in 3rd and go like hell nailed to the boards up a big hill. Then you'll see > 1600bar.

No faults? No worries. 110 on the flat isn't anywhere like a big enough load to get the pressure up.

Gave the RRS a good flogging, locked in 3rd, like you suggest. Saw over 20,000 psi so happy with that. Thankyou

I only got concerned because I was monitoring my 2.2 Defender and it reads 21000psi at 110kph on a flat road. Ive been comparing "apples and oranges"

[Swamiji05]

I know had the same issue with my Land Rover discovery 32.7 fuel pressure higher god top and knocking noise blowing black smoke card does not respond to acceleration. High-pressure fuel pump is already replaced. Injectors are already replaced. Fuel pump is already replaced. Fuel rail sensor already replaced. I have no idea what to do next. Any advice will really appreciate it.

[Graeme]

The wiring to the fuel pressure sensor needs to be checked. The same DTC on a 4.4 TDV8/SDV8 can be caused by a bad connection in a connector in the wiring to the pressure sensor.

[BradC]

If it's a common enough fault, logging with a Gap IID is a great way to see what is happening.
If it was the wiring as Graeme suggests it'll stick out in the data like a sore thumb. If it's not that, then watching the fuel pressure in conjunction with the volume and pressure control valves in the HPFP will give you more of an idea as to what might be happening.

The manual says : "The wires to the fuel sensor are monitored by the ECM for short and open circuit. The ECM also monitors the 5V supply.
If a failure occurs a fault is recorded in the ECM memory and the ECM uses a default fuel pressure value."

If it doesn't go outside of range far enough to log a code the ECM will use the "default" value and keep winding the pressure up to try and get it to rise. After a couple of seconds of that it'll fault.

From experience, the noise made by the injectors when exposed to maximum rail pressure is hellish. I did something silly when diagnosing my HPFP and jammed the PCV shut at idle, which pushed the pressure to maximum and it sounded like the injectors were going to experience a "rapid unexplained disassembly".

[Graeme]

The wiring fault on the 4.4 only logs the P0088 DTC.