TD5 rough running.

[Tins]

I took my car for a little drive earlier today. All was well until I put my foot down going up a hill, when the fuel filter light and MIL came on, and the engine shut down briefly until I lifted my foot. The filter light went out but I had to restart to clear the MIL. It did this once more but drove home ok. I parked it while I found a fuel filter. When I started it after about an hour it ran terribly and had no power. I’m letting it cool down and I’ll change the filter, and purge the system. But does that ring any bells? I changed the injector harness yesterday for a good clean second hand one.
The fuel should be clean. It has been driving quite well

[Bohica]

Water in fuel, There is a drain at the bottom where the water sensor plugs in you could try draining it se if that helps. The filters are cheap enough. I know a man in Tecoma that might have one!

[Tins]

Water in fuel, There is a drain at the bottom where the water sensor plugs in you could try draining it se if that helps. The filters are cheap enough. I know a man in Tecoma that might have one!

I thought so too. It was the MIL that threw me. Also, tank was drained and filled with new diesel. Course, there could be water and who knows what else in the filter. Luckily I have a filter here. The bloke in Tecoma will only want me to take him fishing.

[sierrafery]

The MIL can be "officialy" triggered only by two things on a Td5: the CPS or TPS, i've seen rare cases when low fuel pressure can trick the ECU into a driver demand fault. Did you check if you get HP from the pump? the fact that you hear it running is irrelevant

Another thing is that the water in fuel warning circuit is a completely idiotic design that's why at a point LR got rid of it. The sensor is connected to the fuel pump relay's output and when it detects water there is a huge voltage drop on that circuit which can affect the pressure, maybe LR wanted to make an extra protection cos if that warning stays on for long it will blow the fuel pump's fuse too. I disabled mine

[Tins]

The MIL can be "officialy" triggered only by two things on a Td5: the CPS or TPS, i've seen rare cases when low fuel pressure can trick the ECU into a driver demand fault. Did you check if you get HP from the pump? the fact that you hear it running is irrelevant

I wasn't able to do that test you said across fuse 21, my MM is too primitive, and then we discovered we had screwed up with the crank sensor wiring. Fixed that, replaced the injector harness and the car fired up and drove at 100 kmh for about two hours going home. I put the pump out of my mind at that point. Car ran fine until this arvo when the MIL thing happened, and still ran fine until I shut it down, then this.
Still, I did give it a full throttle hit to overtake up the hill and that's when it happened, so I guess it may have starved at that point, which could of course be what you said about the pump. Still don't get why it was ok, and now it's like a 5 cyl petrol with three of the leads off.


Another thing is that the water in fuel warning circuit is a completely idiotic design that's why at a point LR got rid of it. The sensor is connected to the fuel pump relay's output and when it detects water there is a huge voltage drop on that circuit which can affect the pressure, maybe LR wanted to make an extra protection cos if that warning stays on for long it will blow the fuel pump's fuse too. I disabled mine

Yeah, I read your posts about it on a thread from around 2105/7 while searching before posting. Seems like a bloody good idea to me. You wondered how many folk would have replaced a pump due to the constant fuse blowing.

I'm going to do the filter anyway, as it's been sitting around, on and off, for more than four years. But if the pump is down in HP, would that cause the seriously rough idle, rev up ok, but absolutely no power? Unless it's allowed air into the system I guess. Not sure if it can.

I appreciate your input, and I'm sorry I'm so long winded, but four years! I want it to go, and I've had no hands on stuff with a D2 TD5 for longer than that.

[sierrafery]

One of the symptoms of a pump not delivering enough pressure is that the engine is running fine untill some power is needed, the filter is on the return and LP circuit, the HP is delivered directly to the head.

[Tins]

Another thing is that the water in fuel warning circuit is a completely idiotic design that's why at a point LR got rid of it. The sensor is connected to the fuel pump relay's output and when it detects water there is a huge voltage drop on that circuit which can affect the pressure,

Re-reading your reply, maybe that is exactly what happened. I was giving it some juice, up hill, and the water freaking sensor kicked in, the huge voltage drop to the pump caused the " I'm not here anymore" from the engine for that moment when I needed all the fuel it had and then it all settled down when I backed off....
Hmm. Still can't figure why it's idling like a red motor with four of its leads cut.

[Tins]

One of the symptoms of a pump not delivering enough pressure is that the engine is running fine untill some power is needed, the filter is on the return and LP circuit, the HP is delivered directly to the head.

You posted this while I was replying to your previous. Could the stupid water filter thing have caused this? I gave it a bellyfull a few times coming home with no probs.
I seem to recall the filter light coming on a few times before the car went into hibernation, even though I changed the filter and cleaned the plugs etc.

[sierrafery]

You said that you fitted used injector harness... that's something which doesnt help at all with the symptoms, you need a diagnostic tool to watch live data for a clear answer. To rule out the water warning unplug the sensor and drive it so.

[Tins]

You said that you fitted used injector harness... that's something which doesnt help at all with the symptoms, you need a diagnostic tool to watch live data for a clear answer. To rule out the water warning unplug the sensor and drive it so.

Yes, my motivation may seem strange, but I was under some pressure to remove the car from where it was. I had no access to a nanocom for most of the time there. I will change the filter tomorrow ( needs to happen ) and give it a go with the plug off the sensor. What you say makes a great deal of sense.

[Bohica]

Mine dopes not have the water sensor, never had as as far as I am aware. You have access to a Nanocom now? I know a man who knows a man, but he likes to go fishing.
The lack of power up hill is how mine problem started I narrowed it down to injectors or HP fuel pump. It was the HP fuel pump. I bought a fuel pressure tester.

[Tins]

Mine dopes not have the water sensor, never had as as far as I am aware. You have access to a Nanocom now? I know a man who knows a man, but he likes to go fishing.
The lack of power up hill is how mine problem started I narrowed it down to injectors or HP fuel pump. It was the HP fuel pump. I bought a fuel pressure tester.

Yours is a 2A. There was, I believe, a recall on them, and the sensor was eventually deleted.
I do know someone with a Nanocom, Julian. Don't think the car would climb the Westgate at the moment though. Should be someone over here. After all, I went out to peoples places with mine when I had it.

Sierrfery is one of life's gurus on this stuff, so I'm going to give his thinking a go tomorrow.

[Bohica]

Yours is a 2A. There was, I believe, a recall on them, and the sensor was eventually deleted.
I do know someone with a Nanocom, Julian. Don't think the car would climb the Westgate at the moment though. Should be someone over here. After all, I went out to peoples places with mine when I had it.

Sierrfery is one of life's gurus on this stuff, so I'm going to give his thinking a go tomorrow.

Well if you want to borrow the fuel pressure tester..

[Tins]

I was thinking of taking the fuel pressure tester to you.

Sassafras? you wouldn't go that far in your holidays... Oh, wait, it's on the way to Toolangi.... Sure, bring the FPT... and leave it and the Nanocom, you'll only break it....[bigwhistle]

Seriously, Julian, thank you. Let's see how I get on with the simple things suggested first. Car might be fine with a little TLC.

[discorevy]

Don't forget to check fuses , did you solder and heat shrink the wiring to the crank sensor ?

[Tins]

Don't forget to check fuses , did you solder and heat shrink the wiring to the crank sensor ?

Yes, and I did my best to maintain the shielding by using the same wires off the donor car. However, now it's cooled down I'll go over everything I did, as well as do what has been suggested so far.

[Tins]

So, changed the filter. No water there, but plenty of dirt, which is the point i guess. Purged it, went around the wiring and it started up just fine. Going to take it for a drive with the water sensor thing off.

[Tins]

It's driving really well unless I give it full throttle. I think I'll bypass the boost control solenoid and see what happens then.

[sierrafery]

Remove fuse F2 and try so cos then the solenoid should be open all the time as like it's bypassed

[Tins]

Remove fuse F2 and try so cos then the solenoid should be open all the time as like it's bypassed

Excellent! thank you.

[sierrafery]

I should have mentioned F2 engine bay

[Tins]

I should have mentioned F2 engine bay

Yep. Sussed that.

[slug_burner]

My money is on the fuel pump. Although in my experience the engine idled ok, under load the engine had no power and was just as if starved for fuel. Car was able to tick along on the dirt track, as soon as it got on the bitumen the fuel supply was not up to it.

[Tins]

My money is on the fuel pump. Although in my experience the engine idled ok, under load the engine had no power and was just as if starved for fuel. Car was able to tick along on the dirt track, as soon as it got on the bitumen the fuel supply was not up to it.

In this case I don't think so. I was prepared to agree, but the only time it has a problem is when I floor it, and then it takes a few seconds. The rest of the time, including driving around here, freeway driving, going up a certain track near here, it's fine. So, under load it's fine, but full throttle it fails. I'll try the boost solenoid first. It's cheaper.

[Bohica]

No need to buy the whole thing.

Land Rover Discovery Defender TD5 Fuel Pump Kit Genuine VDO Made in Germany 4103590928344 | eBay (https://www.ebay.com.au/itm/Land-Rover-Discovery-Defender-TD5-Fuel-Pump-Kit-Genuine-VDO-Made-in-Germany/164379660495?epid=2284694266&hash=item2645ca90cf:g:PuAAAOSwAjlgNzOv)

[Tins]

I had the tank out, and the pump out of the tank. Don't ask. The pump housing thing was broken.
169053169054169056

So I did this:

169057169058169059

Seems to work.

[Tins]

Remove fuse F2 and try so cos then the solenoid should be open all the time as like it's bypassed

I think that did it! Thanks again.

[Tins]

I think that did it! Thanks again.

Spoke too soon. But it's so random I'd better go over all the wiring for a potential short or something.

[maxperformance]

Can you explain what exact happened when you "floor it" then "it fails"? Does it surge/jump like short of air or fuel, or does it stop/stall immediately, or it doesn't go more revs than 2700rpm-3000rpm, or it doesn't response in a few seconds then slowly increases the power as normal, or how it "failed"?
In this case I don't think so. I was prepared to agree, but the only time it has a problem is when I floor it, and then it takes a few seconds. The rest of the time, including driving around here, freeway driving, going up a certain track near here, it's fine. So, under load it's fine, but full throttle it fails. I'll try the boost solenoid first. It's cheaper.

[Tins]

Can you explain what exact happened when you "floor it" then "it fails"? Does it surge/jump like short of air or fuel, or does it stop/stall immediately, or it doesn't go more revs than 2700rpm-3000rpm, or it doesn't response in a few seconds then slowly increases the power as normal, or how it "failed"?

First time it happened I was driving up a hill and accelerated and it lit up the MIL, the fuel filter light and it lost power and surged until I backed off. I was able to drive it to the top of the hill, and then I restarted it.
Next time I was pulling away from the lights and wanted to see how the shifts were going at full throttle. This time it lit up both the lights, lost all power and stalled and refused to cooperate until I shut it down and restarted it. I thought, and an indie confirmed, that it might be the boost solenoid that was the culprit. I disabled that and for some time today I thought that to be correct, but then it did it again, this time NOT at full throttle but going up a hill. I'm beginning to suspect that my wiring job may not be as good as I thought. The CPS wiring was what was damaged.


The MIL can be "officialy" triggered only by two things on a Td5: the CPS or TPS

I'll also grab the TPS off the other car. I was planning to do so anyway.

[maxperformance]

I got and sorted exactly the same symptoms on my first TD5 Auto D2 01 135k kms but without MIL light on (it might be a quick flash light of something at that time that I couldn't recall).
Do you have this issue happened constantly at a certain revs range (say between 2500 - 3000rpm)?

[Tins]

Do you have this issue happened constantly at a certain revs range (say between 2500 - 3000rpm)?

No. In general it runs just fine. Then this bobs up. I just gave it a good drive and it didn't happen. But it happened twice earlier today. I am going to completely rewire the CPS to eliminate that.

[maxperformance]

I remember that the issue would not happen unless I went up hills and push floor the pedal then it would surge/hiccup constantly at around 2700 - 2800 revs and would not go past that revs, and felt lost power too (which means with a heavy load or very steep hill it will stall). While on normal roads it would drive totally fine. Turned out a bad MAF sensor and a wrong position of turbo waste gate rod.
But it seems your issue is a bit different. Hopefully you can sort it out quick.
No. In general it runs just fine. Then this bobs up. I just gave it a good drive and it didn't happen. But it happened twice earlier today. I am going to completely rewire the CPS to eliminate that.

[Blknight.aus]

can happen if the purge valve on the LP side is stuffed open.

[Tins]

can happen if the purge valve on the LP side is stuffed open.

Hmm, another curve ball from the expert pitcher. Thanks, Dave, I think. How would I test for such a thing??

[Blknight.aus]

Hmm, another curve ball from the expert pitcher. Thanks, Dave, I think. How would I test for such a thing??

with difficulty,

you can sometimes hear it on the pump prime sequence if theres air in the system, it just sounds wrong, another way is a comparative listen for the pump loading up.

[Tins]

with difficulty,

you can sometimes hear it on the pump prime sequence if theres air in the system, it just sounds wrong, another way is a comparative listen for the pump loading up.

Great. I'm a little hard of hearing these days.