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[DHR123]

For the last couple of days a new problem has arisen. 1999 (pre facelift) 3.0 MV6 Estate. Very hard to start (usually starts "on the button") and when it finally does get going it is very "lumpy" and misfires for a minute or so (EML light is on or flickering). Then settles down but revs will jump to 1,500- 2,000 until engine reaches normal temperature, after which all is fine. Had similar but not quite the same problems a year or so ago which turned out to be the temp sensor for the fuel injection but in that case the revs shot up after the engine reached working temperature and stayed that way. ICV has been checked and cleaned (not usually a problem on 3.0 engines as a rule) DIS pack and crank sensor both replaced in last 12 months. Any ideas? Maybe this is one for "the Doc" if he is not relaxing in his villas in the Bahamas! Regards. David.

[Matchless]

Could be a leaky injector allowing fuel into the manifold after switch off, the resultant very rich mixture makes it difficult to start and causes idle problems untill the excess fuel is used up.
Surprised the EML comes on though, it cant be emissions based until the sensors are hot enough for the fuelling to enter closed loop control, suppose it could be the idle control valve complaining that its at the limit of travel and it still cant get control of idle speed.
Simple test is to hold throttle open during cranking, if it fires first time then thats a good indication that there was too much fuel / too little air. Another check is to depress the schrader valve on the fuel rail immediately after turn-off, this will give you a feeling for 'normal' fuel pressure, then repeat test before start-up after a few hours standing...little or no pressure indicates an incontinent injector.

Other possibilities are sticky idle air control valve and sticky EGR valve.

[TheBoy]

Initial feeling is unmetered air getting in - egr, poor hoses, plenum o rings etc...

[Admin]

Try matchless' test first, that will eliminate/prove the leaky injector scenario.

If it still does it then remove idle control valve and clean with carb cleaner. Lubricate with 3in1 oil and replace (make sure it goes in properly), plug in connector and restart.

If it still causes a problem after that then you need to go looking for inlet leaks....