1.9d Non-starter Y-reg 2001/2

[Thunkclunkpffff]

Hello to all.
Hate to make my first post a cry for help, but needs must.

Car's been starting on the button without problems, till 2 days ago, when on a particularly damp, cold (but not extremely so), early morning, when it started fine, but then the engine started "hunting" (revving up and dropping, up and then dropping). After a minute or so, this behaviour disappeared and then ran as normal.

Because of this, I told the "missus" to depress the accelerator 1/3 when starting on a cold day.

Then today, she started the car on 1/3 throttle, and it started and ran for about 4 seconds, but then died and wouldn't restart.

SYMPTOMS: engine fires-up nicely when fed carb-cleaner thru the air intake; no pressure in the fuel-line priming-pump next to fuel filter housing, even after repeated depression for several minutes; have fully recharged battery - fine; plenty of fuel, although had been run down into red on fuel guage before last refill; pre-heater light working as normal;
upon consulting owner's manual, it states "do NOT depress accelerator when starting the engine"; engine kill switch has not been actuated (although there is a plastic band around it where someone has tried to hold it depressed, in the past).

QUESTION: is it possible that starting the engine on 1/3 throttle could have caused a fault in the fuel delivery/activation sensors/relays, leading to a fuel-shut off being actuated somehow, somewhere?

Very grateful for any input.

Thanks
Roscoe:

[brodfather11]

You are not getting fuel where it needs to be. The "bulb " should get hard after pumping a few times .

The engine hunting is a sign that you are running out of fuel or not drawing enough. Are you sure that you have enough fuel? and diesel not petrol. if so then the pipe between the bulb and fuel tank is faulty and is not drawing fuel. It may have rubbed a hole in it somewhere.

And to your QUESTION , No, starting with throttle open should not cause faults in the fuel system. :thumbsup:

[Thunkclunkpffff]

You are not getting fuel where it needs to be. The "bulb " should get hard after pumping a few times .

The engine hunting is a sign that you are running out of fuel or not drawing enough. Are you sure that you have enough fuel? and diesel not petrol. if so then the pipe between the bulb and fuel tank is faulty and is not drawing fuel. It may have rubbed a hole in it somewhere.

And to your QUESTION , No, starting with throttle open should not cause faults in the fuel system. :thumbsup:

Thanks for the swift feedback. Your experienced opinion confirms one of my own rather uncertain suspicions, in that the problem is a fuel delivery problem, although, I also lacked knowledge to rule out the hypothetical scenario of a fuel-pump being defeated by the ECU arising from a throttle-sensor (or similar) being faulted due to starting on 1/3 throttle when the manual specifically forbids using throttle on start-up - now clear in my mind, thank you again.

Have checked the receipt - definitely a 1/4 tank diesel was purchased 10-miles before to this failure.

Another idea crosses my mind - is there any way to determine whether there is a fuel-tank mounted filter/pump/mechanical-lifter on these late Mk1's (priming pump on the fuel-filter housing = 1.9DW, if pics in the Haynes manual aren't lying), which may have become blocked by sludge from consistently motoring on low-tank levels?

Thanks again

[brodfather11]

The fuel pick in the tank has a rough gauze designed to strain out any large bits of debris, the fuel filter will stop any fine dirt/particles/water from getting to the fuel pump. The injector fuel pump not only feeds pressurised fuel to the injectors it also sucks fuel from the tank through the fuel filter.
The immobiliser stops fuel being delivered to the injectors.

Faults can occur in the fuel pick up, like a split, so that the fuel in the tank will not be sucked to the fuel filter. This can be tested for by filling up the tank so that the fuel will cover the split and stop any air being drawn through the split.

The priming pump on the fuel filter housing can also give trouble and draw air into the system, if you cant get it to pressurise then you need to see why not.

[Thunkclunkpffff]

The fuel pick in the tank has a rough gauze designed to strain out any large bits of debris, the fuel filter will stop any fine dirt/particles/water from getting to the fuel pump. The injector fuel pump not only feeds pressurised fuel to the injectors it also sucks fuel from the tank through the fuel filter.
The immobiliser stops fuel being delivered to the injectors.

Faults can occur in the fuel pick up, like a split, so that the fuel in the tank will not be sucked to the fuel filter. This can be tested for by filling up the tank so that the fuel will cover the split and stop any air being drawn through the split.

The priming pump on the fuel filter housing can also give trouble and draw air into the system, if you cant get it to pressurise then you need to see why not.

Have drawn fuel through the fuel filter by detaching the filter-housing outlet pipe, attaching a length of fuel-line and sucking on it till it was time to spit. Reattached the outlet pipe, pressurised the line with the priming-pump (although it remained a little spongey, not as resistant as I remember from previous cars), and hey presto - the engine started and ran perfectly.

Went back an hour later - started fine. Did notice a little moistness around the base of the priming pump button itself, so suspect this might be source of the pressure leak, especially as I installed a fresh fuel filter as a precaution when this problem first manifested, and the old filter was well past-due for renewal, and could have been creating excessive back pressure in the pre-filter fuel line.

Anyway to all intents and purposes, problem solved, although final remedy of determining conclusively the source of the fuel-line pressure leak, yet remains.

As a parting thought, do you suppose that starting a cold engine on throttle (which presumably for good reason the owners handbook forbids), with an old and congested filter, could have caused the fuel pump to evacuate without replenishing, thus forcing an air-pocket after the fuel-filter?

Many, many thanks for providing excellent focus upon the salient aspects of the problem!:thumbsup::thumbsup::thumbsup:

Look forward to catching you around the forum in future.