Puma engine rattle under acceleration

[Brid]

Under acceleration (esp from cold), I get a rattle from the engine. This morning was the worst I have experienced.

It is a real CLATTER rather than a knock. No smoke at all. It happens above 2000rpm & even light gentle acceleration will cause it. It does tend to disappear when up to temperature.

The oil stays in good, clean condition. My scan gauge hasn't picked up any fault codes at all. The engine light doesn't come on.

Anyone know of any possible causes? I sort of suspect it could be an injection problem...maybe. Maybe a sensor playing up, or computer issue??

Any comments would be welcome.

Thanks
Brid

[RR P38]

What millage on the engine?
How old is the oil? correct grade for climate?
Oil pump good?
How cold was it when you started it up?

[Brid]

This engine has done 68,000km
Oil is due for 10,000km change now
Oil pump and pressure are fine
Not a cold morning at all...guess 15C

[PAT303]

Wasn't there a software patch for this problem?. Pat

[Drover]

Sounds like too much rail pressure....

This will cause it sound like a bag of spanners being tossed around under acceleration.

[TimNZ]

Hi Bird,

My 2010 was doing the exact same thing you mentioned, hasn't done it since the EGR was changed though.

If the vehicle is out of warranty you could try disconnection the EGR electrical connection and see if the rattle goes away. The engine warning light will come on eventually however. This can be cleared with a scangauge or similar, or just plug the EGR back in and the light should go out again after several driving cycles.

Cheers,

Tim

[Brid]

I just came home from a cold start, and the rattle was apparent under acceleration or load till temperature reached around 75C. Then is was OK again as it warmed up further. That's a good thought about the patch Pat30, as it doesn't seem like the injectors themselves to me & no smoke at all.

I wonder if Drover's thought about rail pressure too high could be related to engine management or crook sensor. Maybe I'm getting too much rail pressure if the computer thinks the engine is running colder that it is??

I'll disconnect the EGR electric connection tomorrow morning TimNZ, and see what happens. Thanks for those comments, and if anyone has any further information on the software patch, could you let me know please?

Thanks
Brid

[Geezer]

Hi Brid, I have similar rattle also when its cold, not very loud, almost sounds like a small plate rattling which I notice more at night. Mine is new Defer with less than 7K on the clock and I'm still investigating........
any other knowledge on this would help as you know the stealers just look at you when you say there is a rattle somewhere!

[Brid]

Hi Geezer
My rattle did sound like a loose metal shroud rattling away for ages, but has just become more obvious & louder. Could be similar. I'll certainly post whatever I learn about it.
Brid

[Brid]

This morning I disconnected the wiring plug to the EGR, as TimNZ suggested, and reversed up the driveway. Then I noticed that it had gone into limp home mode, so I reconnected it and continued. The rattle was pretty minor compared to yesterday's, so there may be some connection...time will tell (perhaps). Anyway...thanks TimNZ, it was worth doing.

One thing is for sure...this rattle is not the sort of thing I have ever encountered with mechanically controlled diesels, and that makes me think more along the lines of faulty sensors, connections, control glitches.

Brid