Focus 2.0 TDCi starting probs getting worse

I posted about my Focus 2.0 TDCi and its warm starting problem a few weeks ago. It went through a period of starting normally but now the problem has returned and is getting worse.

It now takes two attempts to start from cold. I thought at one point that it could be the battery not giving it a good enough crank but tonight I noticed air bubbles in the line out from the fuel filter when the engine is running. Not just one or two but quite a lot.

I tried to bleed the filter using the valve on top of the filter housing but didn't seem to get any air or fuel out. If the filter was blocked, would that lead to air being drawn in? Is the filter a DIY job? I've read a lot of stories about the filters on these engines being very difficult to prime.

TIA,

Reply to
Paul Giverin
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Dunno about the Focus and don't think I saw your original post. I had a Peugeot where the fuel line, which ran under the car, corroded somewhere back near the tank and allowed progressively more air in. Eventually the car got hard to start and wouldn't idle.

Air only gets in if there's somewhere for it to get in. There shouldn't be, whether the filter is blocked or not.

Reply to
Douglas Payne

I would add a clear bit of pipe before the filter and see if there are bubbles there, if so work back till you find the leaky bit, if none then fix the leak at the filter.

I expect that the air is getting in at the filter, but if the pump in the tank has a fault?

I had a problem years ago with an xr2i, if the tank was completely full it would run fine, but if it went below about half way it would stop, when I removed the fuel pump I found that the pipe between the pump and the outlet was cracked, so it was just blowing the fuel out inside the tank, with fuel above the crack it could still make enough pressure to run. I believe yours has a fuel pump inside the tank and so it may be putting air in inside the tank, which is why I suggest adding some clear pipe before the filter.

Reply to
Mrcheerful

A couple of months ago I posted a problem with my Focus 2.0 TDCi. This is just a follow-up in case anyone with similar problems wants to know the outcome.

The symptoms were that the engine would often start and die immediately. It would start and run fine on the second attempt. Apart from that, the engine ran perfectly. I initially thought the starter wasn't getting the revs up sufficiently and a battery test showed the voltage slightly down at 12.4 volts. The battery was 5 years old so I replaced it even though I wasn't convinced it was the problem........ and it wasn't.

Looking at the engine when it was running, I noticed air bubbles in the line from the fuel filter to the diesel injection pump. About every 30 seconds I would get a rush of bubbles. I was sure that this was the problem. I thought the air leak might be from the filter housing so I fitted a new filter and seal for the housing. This didn't make any difference.

I thought the air leak may have been from the fuel pick up/fuel pump in the tank but I wanted to try and pin it down. I don't mind paying to have problems fixed but I didn't want to pay a load of money on fault diagnosis which may be inclusive. I tried to get in touch with a friend of a friend who is a Ford technician but while I waited for him to get in touch, I noticed the problem had stopped and two months down the line has not reoccurred.

I'm pretty sure I now know what the problem was. At the time I was working a 3 month contract and filling up at a service station away from home. During this 3 months, I filled up exclusively at this Shell place (on the A11 near Attleborough). I am now convinced that the problem was contaminated fuel. What I thought was air bubbles I now believe to be water and I reckon that would explain the starting problems. The problems stopped when I stopped using that filling station.

Reply to
Paul Giverin

"Paul Giverin" wrote

I have sometimes wondered what air bubbles would do to a diesel engine. My thinking is that if the hp pump pressurises the rail to 1300atm, any air bubbles from the lp side should be compressed to nothing. Could bubbles really have any effect?

I assume that with a lifter pump in the tank, eliminating the need to keep a siphon, running out of fuel is no longer a problem.

Reply to
DavidR

Yes, they stop the pump priming, and as the pump displaces a fixed low pressure volume there is no high pressure

You still need to get the air out of the pump though, some designs do this more succesfully than others.

Reply to
Duncan Wood

You say "pump". If there is an lp pump and an hp pump which are you referring to?

Ditto, which pump? In cr systems are there any hp pumps not made by Bosch?

Reply to
DavidR

The HP pump. On almost anything pre Common rail theres 3 pump, a lift pump in the tank, the transfer pump at the back of the High pressure pump & the high pressure pump itself, the last two ar inside the same housing.

Common rails slightly different & they tend to self prime better than the old systems. Almost all the old systems had a lift pump, priming that wasn't normally the issue.

All the usual suspects make common rail systems, Nippondenso & Delphi are probably the commonest

Reply to
Duncan Wood

"Duncan Wood" wrote

Thanks

Reply to
DavidR

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