Ocaisionally, such as today after a week standing in the driving rain, my '98 V6 mondeo doesn't like to start. Cranks very well - and after about 30s of cranking 1 pot will start to fire.... another 30s of cranking will have another couple of pots catching, and then it's away - with clouds of white smoke. Then it will be fine for a long time. Nothing obviously up with the motor. Dousing what I can see of the HT with WD40 doesn't appear to make any improvement.
Any ideas what's up with it?
Thanks
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W
Do you ever have to top-up the coolant?
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No. Never. Had these symptoms for about 4 years. Occurs about once or twice a year, is all. Had the motor from new. 120k miles. Cranking speed is high - which makes me wonder about the compression - but everything else seems normal. Oil consumption not enormous.... probably a couple of litres per 10k.
Regards
M
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W
Sounds like it's not fuelling correctly and floods before it struggles into life. Only a long-shot; but maybe the coolant temp sensor?
The white smoke might have suggested anti-freeze getting into the inlet side; but if there's no coolant loss.... Maybe if you take a plug out next time it won't go and see what's on it.
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Does the V6 have an idle air control valve? I'm convinced these things can partially seize when left unused for several days. Does the car start better if the throttle is slightly depressed when cranking? The fuel injectors should switch off after a few seconds cranking, so try stopping cranking, let the car sit for a few seconds and try again. Alternatively, open the throttle fully and crank to clear out the unburnt fuel.
4 cylinder Duratecs have a known problem with starting that appears to be linked to EGR and/or idle air control valve. The cheap fix appears to involve opening the throttle after the engine is switched off. I understand this clears the inlet manifold of exhaust fumes, presumably from the EGR(?)
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Thanks guys - I don't know the answer to these all these issues. I did try partially depressing the throttle slowle to allow more air in - but it didn't seem to help.
Engine defininetly sounds like too full of mixture and plugs wet... but at once or twice per year, I don't get many chances to play with it. The other thing that has surprised me is the speed and eveneness of the cranking before it fires at all. Normally it fires first piston up, so I never hear it crank. But today, it's almost as though there were no plugs in it - certainly not easy to detect the compressions loading the starter motor. If it hadn't been doing this for 40k miles I'd be more worried there was no compression. But it's not cold that causes a problem - it's wind and rain.
At twice a year, I can live with it.... but I'd like to understand it.
Regards
M
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The partial depression of the throttle only works (if at all) at initial cranking, otherwise the injectors switch off. A good battery and starter motor should turn an engine over very swiftly. Rain? How old are the plug leads? Mondeo Zetec 4 cylinder engines are known for using plug leads and (sometimes) coil packs. Have you seen wet plugs?
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Hi Mickey- your advice is interesting. If the injectors switch off, then what, after 45s of cranking, does the engine run on when it finally fires enough to run without the starter?
I think the plug leads and certainly the coil are 120k and 8 years old. Time for a new set do you think??
I'll have to wait till it refuses to start again before whipping a plug out... and looking at the beast, getting a plug out might be a challenge....
Regards
M
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The injection will only turn off if you go to full throttle while cranking.
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The good old Ford method for clearing a flooded injection engine, full throttle & give her a spin with the starter.
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The injection will only turn off if you go to full throttle while cranking.
No, otherwise the cat will be contaminated with unburnt fuel during extended cranking at no or minimal throttle openings. But perhaps the ECU disables the injectors temporarily (not fully) during extending cranking as per MEMS (Rover).
I thought initially that the heated oxygen sensor would instruct the ECU to switch off the injectors if unburnt fuel reached the exhaust, but the sensor is probably switched off during cranking and initial cold operation. I previously found a website detailing Ford ECU operation, but can I find it now? Of course not.
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.... and I should have said:
Yes, the injection should turn off if the throttle is opened fully during cranking. It should also switch off (perhaps intermittently) during extended cranking with no throttle to prevent flooding.
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Hi Mickey- your advice is interesting. If the injectors switch off, then what, after 45s of cranking, does the engine run on when it finally fires enough to run without the starter?
It is possible that it takes that long to clear the flooded engine. It's also possible that it takes that long for the Idle Air Control Valve to set at the right position. It is even possible for the ECU to signal intermittent (not total) shutdown of the injectors. I think the plug leads and certainly the coil are 120k and 8 years old. Time for a new set do you think??
If it was a 4 cylinder Zetec then yes, definitely try changing the leads, replace with Ford leads. I'd leave the original coilpack until you're certain that's the problem.
MEG provides a lot of useful advice
www.fordmondeo.org/forum/fusionbb.php?
Flooding used to mean lots of black smoke and a stench of unburnt fuel, perhaps EFi cars don't allow flooding to that extent? I've seen the white smoke thing with a 4 cylinder Duratec engine with a faulty IACV and lots of cranking. The problem was a lot worse when the car was left for a few days in cold weather. The cheap fix was as previously posted: open the throttle after the ignition was switched off, also linked to exhaust gas recycling I think (have I written that somewhere else?)
Good luck
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www.fordfuelinjection.com/ is not the website I'm looking for, but it contains a lot of info about fuel injection systems.
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Micky - thanks for all the info. Of course today it's behaving perfectly. Starting first piston up. Runs like a dream...
I'll study the info from you - much appreciated.
Regards
M
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Two clues, stood in heavy wind and rain and White smoke (suggesting steam) lead me to think maybe the air intake feed tube is partially filling with water which gets sucked into the air filter and initially wets the plugs and causes them to short out. After the excess water has gone through the plugs start to dry in the airflow and she starts up, the water which is now in the cats or exhaust produces the steam. IIRC the feed tube is u-shaped on the Mondeo i.e it starts up high near the front grill, drops down into the wheel arch then up to the air filter. The Mk3 V6 one has drain holes in the first part. The solution is to drill a small drain hole in the bottom of the feed tube. to check if this is the problem, you could temporarily disconnect the feed tube proir to starting after the car's been standing and see if you still have the problem.
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Kith - that sounds a good thing to check out. This is Mk II - so maybe no drain holes? Anyhow should be fairly easy to check. I'll have to wait till weekend when I've got the daylight - but thanks again. Symptoms feel right - drying plugs. And if I'm not mistaken I still might have had a partial fire first piston over TDC, but then nothing but cranking for 30s till one pot starts to cough.
Regards
M
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let us know how it goes ;0)
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