loss of engin power

hi guys p38 deisel got another problem.
the last few times on start the engine idles a bit lumpy. whan warmed up abselutaly ok drives nice. on the way home befor the engine loss power it was still runing but foot was to the floor but there was no power in the engine just as if it had loss boost pressure only just got in so not had a propper look yet any idears or things to look for any help would be nice
thanks tony

was there any excessive smoke coming out of the exhaust.

hi mate no exessive smoke at all. no strange nosies the power just droped off.

Have you changed the fuel and air filter lately?

spannerwanker said:

Have you changed the fuel and air filter lately?

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to be totaly honest m8 no i have not changed the fuel and air filter for a long time bad i know i have notested the air filter is very dirty. i am going to pop out later and get one will let u know
tony

poped out befor to get a new air filter and fuel filter. car runing just perfect thow not tuched it since last night. but runing nice again covered about 15 miles on the way home i am shore the power droped off again but as i was expecting the car to loose power my mined may have been working over time if that makes senceput new filters in not been out in car yet.
all thow as i was checking round engine everything looks ok all pipes conected ok none perished or split.
the one thing i have found if any body can help me identify it is there is a sencer that has been bypassed.
as u may know it is the bmw diesel engine on the right hand side of engine under the inlet manifold there is a sencer that i am pritty shore it is screwed in the the head it is between number 4 and 5 glow plug i am thinking it is the engine temp sender it has a green plug.what some body has done in unpluged the sencer got another sencer that looks the same and atached it to the bulk head and conected to wires to the plug i am trying to fined out what the sencer is monetering because at the mo it is just picking up the air temp in engine bay.
as i say it has a green plug socket any body reconise this.
thanks tony

ok changed air filter and fuil filter car runing perfect.
been out to day covered 45 miles on motor was was on cruising at bout 70 then loss of power puled on to hard sholder sat ticking over wondering what to do put back in to drive had full power again getting back up to speed to regoin motor way and loss power again. sat ticking over about 3 minits tride again had full power again just about to regoin motor way again loss power again.
the AA recovered me off the motor way to a safe place drove back home about 3 miles car runing ok again.
please any body got any idears.
allso i live in warrington between manchester and liverpool any body know any garage i can go to or spesialists in my area
desperate for help
TONY

hi tony tr this guy he in b/head his name is ian 0151 6453342 if he cant help get back to me j