Renault Megane scenic RX4 P-M DCI - White smoke from back of my 52 plate scenic 1.9TCi

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Thu 17 Oct 2013 15:22
Renault Megane scenic RX4 P-M DCI - White smoke from back of my 52 plate scenic 1.9TCi - rosco38

Hi. I have the above car which is doing some strange things. If you start it cold there is not any excess smoke from the exhaust. You can leave it running on idle and get it warm and then rev it as hard as you like stationary and still no smoke. I can leave it running on idle for two hrs then go out and rev it and still no smoke. However as soon as I start to drive it within 200 yards there is white smoke billowing out. I then park it up still running and its still smoking like crazy. and I can leave it running for an hour and its still billowing out smoke even on idle. BUT if I turn it off and leave it half an hour or even less I can start it again and not a whiff of smoke nomatter how long its run for or how hard you rev it!!. But the second you drive it 200 yds its back to killing off anf one thats following you. Its using ZERO coolant and NO oil at all HELP!!!!!!

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Thu 17 Oct 2013 16:01
Renault Megane scenic RX4 P-M DCI - White smoke from back of my 52 plate scenic 1.9TCi - dan86

The turbo wont spool up on idal no matter how harf you reve it as there is no load on the engin but once you are driving the turbo will spool up so it maybe turbo related. But white smoke cane be a sign of head gasket problems. Is there any white sludge on the oil cap?

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Thu 17 Oct 2013 19:02
Renault Megane scenic RX4 P-M DCI - White smoke from back of my 52 plate scenic 1.9TCi - Bromptonaut

You need to determine if it's smoke, either oil or unburned diesel or steam from coolant. The best tool for this are vision and your sense of smell. If it 'smokes' while idling on you're drive then it's easy, otherwise you may need to follow either in a another car or on a pushbike.

Smoke from unburned diesel is grey without the blue tinge of lost oil and has a quite different smell. Pre heat faults, over fuelling and induction leaks can all create excess diesel smoke.

Coolant loss through CHG does not always show as dramatic fall in coolant bottle - the blow by pressures the system and gas replaces coolant. Sometimes CHG failure can cause the coolant bottle level to rise and fall quite dramtically!!

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Fri 30 Jun 2017 17:05
Renault Megane scenic RX4 P-M DCI - White smoke from back of my 52 plate scenic 1.9TCi - sasko petrovski

Hi

I have same isue with my rx4 can you please tell me how did you fix yours!!

thanks

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