Leaking Injector (and replacing fuel hose)

Tesla

Tesla

Tesla

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Bristol, UK
Hi all,

My recent eBay purchase has developed a fault this week. It's a Mk2 Mondeo 2.5 V6.

The car was fine for the first few weeks but now struggles to start after being stood for a while (i.e. overnight).

The engine turns over on the starter but won't fire. I can get it to start by pressing the throttle a bit, it coughs for a few seconds and then is fine.

I think the starter and battery are strong.

I am thinking perhaps a leaking injector. I don't get any smell of petrol when it struggles to start though.

If the car has only been stood for a few hours it starts perfectly, every time.

Am I right in thinking that if I pull the fuel pump fuse later tonight making the car cut out from fuel starvation that will mean that there is no fuel to leak through the injector? So, in theory it would start on the turn of the key in the morning?

I have never worked on a car's fuelling system and only am thinking leaking injector from a few things I've read online. If it proves to be a leaking injector then what's the fix?

Worth mentioning I broke some vacuum pipes recently and replaced with some hosing from eBay, I believe the vacuum is for the cabin heater and EGR though. I also cleaned out the idle air control valve to cure the moosing problem common on this engine.

Thanks again guys.
 
Possible air leak on the fuel system?

Fuel draining back to the tank overnight, then the lift pump has to run a bit longer before the fuel rail pressurises and starts.

Could be any of the pipe joints or maybe the fuel filter. (working from general fuel probs here, never touched a v6 mondy)
 
Extrememly unlikely to be a leaking injector IMO. This might make it misfire on one cylinder for a few seconds but wouldn't stop it starting.

A voltage check on the battery during a cold start would determine if it's past it's best.

The coolant temperature sensor should also be under suspicion; these can drift in value over time and cause problems with the cold start enrichment. An excessively rich or weak fuel mixture will give starting problems.
 
Thanks for the replies. The car doesn't sound as if the battery is week, I can hold it cranking on the starting motor but it's not a problem to stick a multimeter across the battery. What values should I be seeing?

IIRC the Mondeo cooling system does use different sensors for the gauge and ECU so it could be possible the ECU coolant sensor is faulty, any other symptoms of this?

I plugged an OBDII machine into the car and no error codes.

I have all the service items for the car inc. fuel filter in the garage. Including plugs, could it be the plugs?
 
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I'd start off by replacing the spark plugs first and see how you get on, especially if yours haven't been changed for a good few years. My Focus used to crank for a good 3-4 seconds before firing up on most cold mornings but since I replaced the spark plugs a month ago it's always fired up straight away on every cold morning start.

Liam
 
Will give the car it's full service today including new plugs and fuel filter and see if it makes any difference.

I might replace the vacuum pipe which goes to the fuel pressure regulator as the other vacuum pipes I broke were so brittle.

From reading around there are so many possibilities but a lot of them have cheap fixes or diagnosis.

Apparently a good test for the injectors is to take them out the engine but leave them connected and rest them overnight on some paper to check for leaks. Would you agree?
 
Managed to break a fuel line today whilst poking around. The length I broke is a piece around 50mm in length. On one end is the quick release connector which is then pushed on to the fuel rail. The other end of the broken pipe is a small diaphragm or valve.

I have tried replacing the broken hose with fuel hose and some small jubilee clips but it leaked.

The original hose had no clamps or such, the fittings are ribbed and the hose was shrunk onto the fittings. I had to slit the old hose length ways to remove it.

Any ideas on how I can rectify this problem? Cheers
 
Tesla said:
Managed to break a fuel line today whilst poking around. The length I broke is a piece around 50mm in length. On one end is the quick release connector which is then pushed on to the fuel rail. The other end of the broken pipe is a small diaphragm or valve.

I have tried replacing the broken hose with fuel hose and some small jubilee clips but it leaked.

The original hose had no clamps or such, the fittings are ribbed and the hose was shrunk onto the fittings. I had to slit the old hose length ways to remove it.

Any ideas on how I can rectify this problem? Cheers
Click to expand...

Buy a new pipe, they are made to withstand much more pressure than a bit of pipe and a few hose clips...
:)
 
The bits of plastic pipe.. are designed to hold more pressure than a Jubilee clip and some 'other' fuel hose.

So you need to get a new 'Quick release hose esk' style' pipe ;)
 
I see. Do you think I'll need to buy the part from Ford? The plastic fuel line of the same spec continues after the valve so it may end up being a mammoth task?
 
fuelline.gif


Hopefully this explains a little better.

The damaged hose is a plastic tube which is shrunk onto the connectors (christmas tree type) at each end and then the rubber hose is just for mechanical protection.
 
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Ok, that wasn't quite what I expected. I know your motor is petrol. But from what you described it sounded similar to my diesel engine fuel hoses, which are a hard black plastic.

You'll have to wait for a fellow Mondeo owner to give some advice sorry :o
 
They are hard black plastic, well nylon I believe.
The rubber hose is just slid over this nylon hose. Just offers protection I guess, the water pump belt is nearby.

Does anybody know where I could pick up some nylon hose. Googling reveals it literally just pushes on after being heated up (with some effort). This would then be an OE repair.

This image shows the fuel line with the rubber hosing slid out of the way a little.

1251824994zp0109091823.jpg
 
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I went to Halfords this morning and bought 1m of 6mm ID high pressure fuel hose. Rated to 12 bar!

The hose came with two fuel hose clamps, these differ from jubilee clips. Unsure how the differ in function, can anyone enlighten?

Anyway, the hose was a much tighter fit than the stuff I had laying around which I used last night. Put it all back together and left it idling on the driveway and no leaks.

Will the pressure in this pipe vary or is it constant? If variable when is pressure at its highest?
 
It sure as hell isn't going to go about 12 bar. :p

If your connections are strong, it should be fine.

As for starting, I'd vote air leak into the fuel system, or more likely, a CTS problem. What happens if you unplug the CTS, does the problem change?
 
The coolant fan seems to kick in when needed so unsure on the CTS, any tests which can be performed?

Can't say I have noticed smoke.

Maybe I will just have to pay Ford to do some diagnostics?
 
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