Mondeo TDCi Lumpy idle

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Sun 24 Jun 2007 22:31
Mondeo TDCi Lumpy idle - espzetec
Some of you may recall that i recently posted about a loss of power at around 3000RPM at motorway speed on my 130ps Mondeo TDCi.

However, now I am getting a lumpy idle at start up and some smoke from the exhaust. The idle settles down after a while and after I have driven it up the road the idle is perfect.
There is always a burning smell when i start it in the morning, but i presume that this is after the turbo was replaced. As I recall it dumped all the oil into the cylinders and intercooler. Could this oil residue be what is causing the burning smell after a night sat on the driveway?

Anyway, any help on the smoke and lumpy idle much appreciated.

p.s. i have heard rumours about EGR valves - could this be the cause? If so, how do i test to see if the valve is faulty?
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Sun 24 Jun 2007 23:23
Mondeo TDCi Lumpy idle - Aprilia
Really, these are of such complexity that you need to take it to someone experienced and with the right diagnostic kit. 'Poke and Hope' does not work on these...
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Mon 25 Jun 2007 11:40
Mondeo TDCi Lumpy idle - espzetec
THanks for reply, however if I had loads of money to spend on diagnostics I would have done so by now. All I'm after is some pointers as to what it may be and if anyone else has similar problems.

I'd like to 'try' and sort this one out myself and not have to take it to the garage and risk being ripped off.
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Mon 25 Jun 2007 13:25
Mondeo TDCi Lumpy idle - cheddar
I'd like to 'try' and sort this one out myself and not have to take
it to the garage and risk being ripped off.


Aprilia's advice is spot on, £50 to get it plugged in to the diagnostics at the dealer would be money well spent and may pay for itself in that you will not be fixing by trial and error.
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Mon 25 Jun 2007 13:36
Mondeo TDCi Lumpy idle - Aprilia
I'd like to 'try' and sort this one out myself and not have to take
it to the garage and risk being ripped off.


You have power loss above 3000rpm, smoke on start-up and lumpy idle. Obviously there is a problem (or more than one problem).
I think you have to accept that there is very little you can DIY on this fuel system - quite apart from the possibility of damaging it, there is a personal safety angle too (Diesel at 20,000+ PSI can be dangerous!).
I think your DIY options will be checking that all the ducting and pipework is secure and leak-free and that the intercooler is free of excess oil residue (a small amount is normal).
Anything beyond that will require input from someone with the training and kit needed to work on these systems.
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Mon 25 Jun 2007 14:04
Mondeo TDCi Lumpy idle - scrapmetal
Your symptons are the exact symptons to that of a nissan primera / xtrail with a YD diesel engine that has a problem with the suction valve on the high pressure diesel fuel pump. Maybe this could be the same fault?
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Mon 25 Jun 2007 20:14
Mondeo TDCi Lumpy idle - stevie1234
Apprilia is right, but I would go further and say TOW it to the garage and have them sort it, I say this only because of problems I have had, also if your intercooler was filled with oil from the turbo, I understand that it should have been cleaned and verified before being used again, might be worth checking if it has.
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Mon 25 Jun 2007 20:15
Mondeo TDCi Lumpy idle - Pugugly {P}
Insurance claim would be the best way to go, it was a genuine accident.
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Mon 25 Jun 2007 20:26
Mondeo TDCi Lumpy idle - Aprilia
also if your intercooler was filled with oil from the turbo I understand that it
should have been cleaned and verified before being used again


Yes, that's correct!
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Tue 26 Jun 2007 15:32
Mondeo TDCi Lumpy idle - injection doc
I totally agree with aprilla & you could spend a lot of money guessing. Take to a competent diesel specialist & ask for their advice & heed it. Its remotely possible the engine has hydrauliked ( somethink like that) and has a conrod a fraction shorter than the rest causing a slightly lower compression causing a misfire cold .
Have the injectors been recoded? very common problem & they do lose there coding.
Regards Doc
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