Diagnose my Mondeo

Thinking about what you said regarding the clouds of black soot from the rear, you may want to think about a fuel system flush, for this to work tho u would need it to run atleast once to pull it through the system.

Regarding non start, an engine will sound different depending on if its no getting fuel, failing on compression, or being chocked, or in the case of petrol (no spark).
Diesel engines work on pure compress, glow plugs warm the air only.

All of the above can be diagnosed through sound, lack of compression means a higher pitch and higher turnover rate, may also hear signs of leaking air.
Glow plugs not working may have similar symptoms too so atleast you can narrow it down a little.
Lack of fuel is less obvious, similar sound but best thing to do is look for unburnt fuel coming out of the exhaust, likewise for over fueling/flooding.

Lack of air would slow turnover rate as there is a negative vacuum, you can hear the engine physically struggling to turn over. (check for pipe kinks and blocked air filter)

lack of fuel, likewise on fuel filters, check for deposits, fuel pump may be leaking or not have sufficient power to deliver fuel, check battery, should register 13 13.3v across +/-

other than the above, it could be a whole array of sensors for engine position, air pressure, fuel relay, emission, or if worst comes to the worst it could be injectors or pump.

Random question, you use any out of the norm petrol stations recently, might be dirty fuel blocking fuel lines

Edit: all the smoke could also point to EGR being stuck open
 
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Interesting, thanks. Any details on why this is?

Crankcase pressure is generated by the movement of pistons up and down in a sealed unit as well as ring blow-by; the systems to deal with it are emissions control via draft tubes or breathers/ventilation system. If this doesn't function properly expected pressures aren't right and the crank assembly fails to operate under vacuum which adds load/stress on compression strokes mainly.

Depending on the car/engine/systems this can manifest itself a few ways, including misfires & crap out the back. Easy test is to take the filler cap off, if its thundering out puffs of air then you have a leak.
 
Would a split hose prevent the car starting?

It made mine an unreliable starter. I had to give it a bootfull to start it and when it did finally turn over it spat out a fair bit of smoke.

If it is the intercooler hose it's a £55 part and takes 10 mins to swap
 
Crankcase pressure is generated by the movement of pistons up and down in a sealed unit

Think about this. A piston that moves up and then down displaces zero net volume and generates zero net pressure :) Crankcase pressure comes from combustion gasses leaking past the rings and the breather system failing to deal with it.
 
*UPDATE*

Just spoke to the garage. 'I've got good news and bad news he says'. My mouth goes dry. 'The bad news is' he says, 'we don't know what's wrong'. Thoughts of homicide enter my mind. 'Good news is, we got in her, turned the key and she started first time, no issues whatsoever'. Wait, whut??

In my shock I forgot to ask him if they'd checked for error codes, but, WTF? It sat on my drive and failed to start on three occasions across 4 days.

They're taking it out for a drive to see if they can get it to misfire so they can at least see what I'm talking about with that, but again, WTF?

I'm thinking water in fuel tank somehow, maybe? Froze in the cold weather and caused a blockage somewhere which has now thawed with the warmer weather? A fuel flush as suggested sounds like the way forward at the moment.
 
Well if the fuel flush doesn't do it, it wouldn't hurt to replace or just check the crank position sensor. Sometimes they break or come loose, and move just enough so the reported crank position to the ecu is wrong. Meaning some days it will fire up first time, some days it won't start at all, as it all depends on the sensor being correct.
 
They managed to reproduce the misfiring finally and a leakoff test has confirmed 2 duff injectors. Just waiting on a call back with prices now :(
 
Ugh.

£636 in parts and labour for 2 injectors, or £1100 for all 4 brand new. I can supply them to him reconditioned, but they don't do it themselves.

********.
 
Perhaps grab a pair from a low mileage car in a scrappie?

Did that on our 406 2.2 HDi at 135k. Replacement injectors were from a 80k miler. Car now at 192k and going strong :)
 
To be honest I need the car back ASAP now as it's now costing me money not having it. I've agreed £590 for the two with him so that's what it's going to be unfortunately.
 
I've seen them on there, but to be honest I don't trust anything on ebay. At least with them being brand new it should be good for the rest of the life of the car.
 
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True, I'd personally not buy them from ebay, but it does give a benchmark on what sort of value they have. Its costing you less than £300 for an injector supplied and fitted brand new - it's not too bad
 
£190 + VAT per injector, then 2 hours of labour to fit.

From what I've read online about other people in similar situations it's not a bad price, just a PITA.
 
It is, a bit of a pain. Unfortunately thats the risk with these sorts of cars - fortunately everything else about them tends to be very reliable. I'd rather have a car that throws me a 600 quid bill in 2 years rather than a £100 bill every 2 months!
 
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