Mitsubishi Delica Owners Club UK™

[Greg82]

Hi. I've  got a strange noise coming from my 2005 3.0 v6. It sounds like a loose low speed bearing rattle coming from around the right hand side bulkhead or engine. I have checked or replaced the various pulleys timing belt and alternator so I don't think it is actually a bearing. It is most noticeable when selecting drive or reverse when the engine is idling cold and when turning the engine off. After doing some testing it seems to make the noise most when the engine is idling while under light load and it seems to get quieter once the engine has warmed up a little. I need to check it again with some help so I can pinpoint the location.

Any help would be great.

Cheers Greg

[Google]

[andyman]

Have you tried listening from under the bonnet? It could by the hydraulic bucket shims/ tappets. There is an updated, modified set available that lets more oil in so you don't get rattle at idle.
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Andy C L300 Super Exceed - over 100 smiles per gallon!

[Greg82]

It doesn't sound like valves and I don't think it's from anywhere low on the main block. It sounds like it's from the upper bulkhead area. Could anything on the EGR system cause it?? It will almost certainly need a good clean but that will have to wait until I tackle the spark plugs in the near future. I can only describe the noise as a mixture of a rattle and static.

[andyman]

Do you notice increased vibration when it is happening? I've had odd rattling vibrations caused by torque reaction to clutch drag, in manual cars, equivalent to the drag in the torque converter when you  engage drive or reverse. Had it with my wife's first Mercedes auto - that was exhaust related, as it was on my Renault under acceleration - vibrating a heat shield.
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Andy C L300 Super Exceed - over 100 smiles per gallon!

[fintious]

Seem to recall someone on the Australian forum with a similar noise and it turned out to be a loose connection on the wiper motor where it links to the arm?
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3.0 V6, Auto. 2005

[Greg82]

I'm convinced it must be something loose but I still can't find it. It seems to happen when the engine changes revs when idling under load. It then gets quieter as the engine settles. It's most noticeable when you turn the engine off and you get a brief second of noise as the engine comes to a stop. I can't hear it when operating the shifter from the passenger side so I really doubt it anything central like the gearbox or main block. I've disconnected the alternator, steering pump and brake vacuum hose with no change. Does anyone know what's under the dashboard or inside the body just in front of the door? It's starting to annoy me now.

[Greg82]

okay. I've just made progress. It only makes the noise if the throttle is closed. It doesn't happen if I switch off at 2000rpm of switch off and hit the pedal.  I think it must be air getting sucked in with the residual vacuum in the manifold. It’s due a good clean out and spark plug change. Thanks for your help. I will let you know what the result is.

[Greg82]

So I've made some more progress and I think it's the idle air controler rattling. I'm no expert in the workings of intakes so there is a chance that the cause is related but elsewhere. When I disconnect the IAC the noise doesn't happen. I took the IAC off and cleaned it and noticed some play in it. I don't know what is normal and bad but it seems like that is rattling. I've ordered an ebay special for £20 rather than £200+ so hopefully it works.