On my Mk 1 Mondeo 1.8 there are 2 metal pipes under the air plenum facing back towards the rear of the car. The bottom one is attached, but the top pipe had "blown off" causing a rasping noise when accelerating and a lack of power.

Just been to Ford who tell me that means it'll need a new cat as it shouldn't blow off. The cat was only replaced in september so I very much doubt that. Where does the other end of the pipe go? I had the air plenum off yesterday and I couldn't see where it went or the pipe. The other bottom pipe goes to this big rectanglar block on the bulkhead.(Exhaust Gas Pressure Differential Valve) (The right one of 3)

The top one feeds off the same copper type tube from the front of the engine but gawd knows where it goes



Ideas please??

 

Was the replacement cat NEW or a used one?????

In my experiance, the main cause of that pipe blowing off is because the CAT has broken up, pieces of the ceramic material will be blocking or partially blocking the exhaust system.

Sometimes fitting a "new" or good condition used cat (downpipe assembly) will not cure the problem because there are still pieces of the old broken CAT within the rest of the exhaust system causing a blockage/high back pressure.

 

Thanks.

If i block that pipe off, would it create some back pressure to possibly clear - blow through the blockage? I think it was a new cat BTW. Do you know where that pipe goes to so I can see if it's still on the car?

Is thre any test I can do to see if it's the back box still bunged up or something?

 

No, that wont work.

No, I dont know where it goes.

This is the way I did it: Disconnect/remove the downpipe, while it's off look inside (exhaust end not the manifold end) and see if the CAT is ok or if it's starting to break up...........Next, look down the exhaust pipe (use a powerfull torch) for pieces of broken cat/ceramic material. Even if you cannot see anything, use a stick/pole to poke down the exhaust pipe as far as you can and feel any dislodged pieces of the old CAT that may be in there.

It could be that the broken CAT parts are even further down the tube...........In that case you will have to remove the whole exhaust syetem, stand it upright (engine side to the ground and try tapping the tube so as to make the broken CAT pieces fall to the bottom.

 

Thanks for such a detailed description of how to go about it.

 

the pipes that come off goes to the silver box at the top of your picture

 

Thanks mechanick! Just back from Fraud where I saw that on their little screen. Unsurprisingly enough, they didn't have any in stock, so I went round the corner to a little garage I've used where I got a length for nowt.

 

This bits new on the car:
(assuming it's the CAT?)



So from there back won't cost much will it?