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Discussion Starter #1
Hi all. I have a 2.4. Aac deisel. 150k on the clock. Brilliant van runs great on motorway but as soon as I hit a slight incline it slows right down.
going over steep hills last week In the highlands of Scotland and was in 1st gear screaming up some hills. now noticing when I turn off ignition I’m getting a thump like noise under passenger footwell? I’m a keen diy mechanic but think it may need a garage to solve this as read it may be timing?Any help appreciated thanks
 

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Has it always behaved in this way ?Or is it new behaviour ?Pump timing will not alter itself as long as the belt has tension etc.But if it has always in your ownership lacked power it could be pump timing ,which has been wrong all along .The thump COULD be a worn out bush in the "dog bone " shaped mount which connects the engine to front subframe .
 

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Discussion Starter #3
Has it always behaved in this way ?Or is it new behaviour ?Pump timing will not alter itself as long as the belt has tension etc.But if it has always in your ownership lacked power it could be pump timing ,which has been wrong all along .The thump COULD be a worn out bush in the "dog bone " shaped mount which connects the engine to front subframe .
Thanks for your reply. We have owned it for a year. It’s gradually got worse. A friend of a friend who’s a mechanic suggested the flap/thump I’m getting from the air intake maybe a sticking valve which then burps out air back once the engine is shut off. The noise is definitely coming from the air intake passenger side. Any tips on sticking valves?

thanks
 

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Maybe dismantle and check air intake pipe and filter for blockages .Shortage of air could also lead to lack of power and it could be gradual .Could the pipe be collapsing ,seen this once before on an industrial diesel and it led to lots of black smoke as it completely was collapsing .Partial blockage ?
 

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Discussion Starter #8
Maybe dismantle and check air intake pipe and filter for blockages .Shortage of air could also lead to lack of power and it could be gradual .Could the pipe be collapsing ,seen this once before on an industrial diesel and it led to lots of black smoke as it completely was collapsing .Partial blockage ?
Thanks I’ll check this out too and report back. Great help from all who’s replied. Thanks again
 

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Thanks I’ll check this out too and report back. Great help from all who’s replied. Thanks again
Hi thought I’d add. The thump like a flap closing is coming from the battery side. The air intake which I thought actually is a vent to the cab I think? And sorry it is AAB
 

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No flap on the air intake for ventilation....unless you have aircon.

I did once read about someone who found a dead rat in the airtake box/filter/pipework of the engine though!
 

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Discussion Starter #11
Quick update. Fitted new fuel filter and not any better. The old filters paper was black so glad I got that done and not much expense or time.
the flap like noise from around glove box area is a mystery. I’ll check out the air intake to see if anything is obstructing the flow and report back.
Thanks again.
 

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Non-AC models have a vacuum operated recirculation flap just behind the blower fan. When turned on this makes a loud flop sound as it slams shut, it could be doing the same opening again once the solenoid valve closes after engine shutoff. Check your recirc button is not pushed in.
 

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Discussion Starter #14
Non-AC models have a vacuum operated recirculation flap just behind the blower fan. When turned on this makes a loud flop sound as it slams shut, it could be doing the same opening again once the solenoid valve closes after engine shutoff. Check your recirc button is not pushed in.
Well how silly do I feel. Schoolboy error of the highest order.
thanks
 

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But not solved the lack of power problem yet ?This flap is a new one on me but I dont think I have ever used that button..
 

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But not solved the lack of power problem yet ?This flap is a new one on me but I dont think I have ever used that button..
The lack of power I will hopefully solve with the knowledge and help on this forum. I know it’s a 1998 deisel and won’t be like a Porsche off the line but I’m sure it’s not set up right. On take off to get any speed the engine is screaming through the gears. Is this normal as it’s not an injection engine? Thanks again
 

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Discussion Starter #18
If your engine is screaming but you are not going anywhere It sounds like you have a slipping clutch to me mate.
It does go but I thought it would be quicker. It slows right down from 70-40 as soon as I hit a hill. Although on hill starts I do have to give more revs and hold the clutch to take off. Apart from this the van is amazing.
around 40mpg. We spend a lot of our trips in the west coast of Scotland and there’s loads of hills to tackle. I’d just like to get up the hills without screaming in the lower gears.
any help appreciated
Thanks
Scott
 

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"Is this normal as it’s not an injection engine? "

Err....it is.....

The 2.4 is a "tractor" engine, will run forever if maintained...but it's a common problem to slow down on "hills"...on mountains...well !
People talk about having to change down on motorways..hilly Scotland is gonna be worse.
I'd hate to have one in Norway!
 

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Discussion Starter #20
Tonight’s update.
removed air intake pipe aswell as the box that holds the filter. No signs of any blockage. The cast section that sits on top of engine had some signs of oil in it aswell as the flexi pipe. Is this normal? I’ve took a video which I’ll try and upload which shows the van idling. Hope this will help. Sounds very rattly.
thanks.
 
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