Freelander 1 TD4 warm start problems

[S1monm]

Hi all not been on for a while. Got a problem with my TD4 taking forever to start when warm.

The HP fuel pump was leaking like a good un so I replaced this thinking I'd kill two birds with one stone. The pump is no longer leaking as expected but the warm start problem is still apparent.

I changed the cam sensor to no avail. So next port of call was the injectors. When hot the fuel rail takes an age to have enough pressure to start the engine. So took car to the local land rover specialists who did a leak off test, after approximately 2 minute they shut the engine down as number 4 injector had filled the bottle, the other 3 were fairly even and had around 25ml in them, number 4 had about 100ml.

Now the interesting bit, I assume number 4 was fooked as it had filled the bottle but the mechanic said this one was working well and the other three looked suspect as they were low. Is this correct as it seems to go against everything I've read?

Cheers

 

[S1monm]

Anyone?

 

[Nodge68]

If the rail pressure is slow to build up. This points to the pressure regulator O rings leaking. If the O ring don't hold the pressure, the fuel simply returns to the tank.

 

[S1monm]

Thanks Nodge, the pump is a recon unit and the poor starting was present with the old pump, hopefully it's not the pump. Spoke to a Bosch specialist who are reconditioning an injector for me, will pick it up tomorrow and get it fitted hopefully curing the problem

 

[guineafowl21]

Now the interesting bit, I assume number 4 was fooked as it had filled the bottle but the mechanic said this one was working well and the other three looked suspect as they were low. Is this correct as it seems to go against everything I've read?

I agree - this is the opposite to how I interpret a leak-off test. If no. 4 is very leaky, it could be preventing rail pressure from building.

 

[S1monm]

The diesel specialist agree the faulty injector is the one leaking the most. Picking it up today, hopefully it'll be straight forward to do.

 

[S1monm]

Picked up the refurbished injector today, couldn't wait so fitted it when I got home at 5:30. Took 45 minutes from start to finish and that was with using a head torch lol. Car now starts first time and much smoother idle.

I've done about 300 miles today and started the job with a hot engine, don't know if I was lucky or whether the heat helped but I pulled the injector out by hand!! The bore was spotless as was the injector tip.

Beer in hand feeling well chuffed

 

[S1monm]

So my problem is back, won't start when warm. Today I've replaced the other 3 injectors and the glow plugs as 3 were duff. To recap I've done the following:

Replaced HP pump with a refurbished unit
Replaced all the injectors bought from a Bosch specialist
Replaced cam sensor

Diagnostic shows no pressure to fuel rail when cranking. LP pump showing 380kpa. Leaving it for a couple of hours allows it to start and HP rail showing 28000kpa at idle.

Any ideas as I'm loosing the will to live.

Thanns

 

[Nodge68]

The HP regulator O rings are a good place to start.

 

[guineafowl21]

Worth another leakoff test.

 

[GrumpyGel]

Rail pressure sensor harness is a known issue?

 

[S1monm]

The HP regulator O rings are a good place to start.

Thanks nodge, Its a refurbished pump though?

 

[S1monm]

Worth another leakoff test.

Bosch refurbished injectors, surely they can't be faulty in less than 2 hours?

 

[S1monm]

Rail pressure sensor harness is a known issue?

I'm considering changing this next but once started it runs perfectly.

 

[S1monm]

I'm now thinking it's an immobiliser fault. Key in position 2 and diagnostic shows; all doors open when they are closed, alarm activated when it's not, bonnet closed when its open, ignition off when it's on, key in ignition which is correct? Any ideas?

 

[GrumpyGel]

What diag box are you using to get that sort of info from an F1?

 

[S1monm]

What diag box are you using to get that sort of info from an F1?

I'm using an Icarsoft I930, also have Delphi 2015 which is showing the same. The thing won't start at all now and it's 2c

 

[GrumpyGel]

Does sound like the pump regulator's O ring or the pressure sensor/harness going by other stuff.

 

[S1monm]

So another £100 quid or so down and still not fixed the thing. Car refuses to start at all now. Bought the overlay harness and fitted it about an hour ago. On the upside I found why the security system was all to cock, three bent pins in the ECU, sorted these and all readings on the scanner looking good.

The battery is now fooked due to the amount of cranking but it still won't start even with jump leads, turns over happy enough but HP pressure still showing 0, occasionally it will go to 2000kpa and then drop straight away. Could be the fuel rail pressure sensor I guess?

Any ideas guys as this is turning in to a very expensive few weeks.

 

[Nodge68]

It still sounds like the pressure regulator O rings to me. If the regulator O ring splits or doesn't seal tight, then the pumped fuel simply flows back to the tank via the return line. This gives the impression of no or very low rail pressure. It's definitely worthwhile changing the regulator O rings as they cost about £5 and take an hour or so to fit.