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638 108CDI popping noise at start up

1091 Views 5 Replies 2 Participants Last post by  gf0012-aust
as above. I've just noticed on warm days, or when the vans been running for a while, that when I restart the engine I get a noise like an "air pop" when I start up.

standing in front of the engine bay, LHS there is a small cannister which has 3 lines coming from it. the left most hose line is completely loose

1) does anyone know what this cannister is? (My PC with WIS has carked it so I can't use the software)

2) has anyone had this happen etc....
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Hi ya, at a guess you are refering to the Diesel filter and one of the lines is not fitted properly. The noise is more puzzeling, if it is more of a chug chug sound it could be a loose injector or injector seal gone, the only other thing i can think that could cause a poping sound is a stuck egr valve. If you can take a picture of the canister and post it so we can identify it

Cheers Martin

thanks, will try and take a happy snap on the weekend. the ongoing noise is similar to "nailing" but settles down when she's done 10-12 kms and/or hits 50+ degs
Hi ya, when you start it up stick your head under the bonnet and see if you can smell or see diesel fumes coming from under the plastic engine cover and look at the right side of the engine bay for a rubber tube that goes nowhere. If there is gunk coming out of this tube or what looks like oil running down the back of the engine ti points to an injector seal gone. The rubber tube is a leak off pipe from the space in the middle of the rocker box where the injectors sit. If there is gunk coming out of this it is diesel that is blowing past the injector seal.

Cheers Martin

P.S the noise goes away as the engine heats up because the metal expands and blocks the leak from the seal
will have to check on the weekend as the poor bugger is now at the panel beaters after an argument with a woman pushing an oversized hardware shopping trolley
got it back from the panel beaters today.

had another look.

cannister left side standing in front of the grille

left hose very very loose, not sealing at connection, centre hose tight, right side hose loose, not sealing on connection

no discharge from other hose by engine block.

I guess I'll find out tomorrow whether tightening these 2 hoses fixes the prob.
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