2.5tdi won't rev above 3500rpm?!?

[pdf11]

hi.
i have a 1999 2.5tdi a4 avant that wont rev above 3500rpm, and isn't that quick getting there. doesnt feel like its in any kind of limp mode, but its as if its 'limited'?. i've unclipped the maf sensor and still no difference. it starts and sounds smooth as it should.
could anyone shed some light on this as i've run out of ideas
cheers

 

[Bradderz_1988]

Try blocking off the EGR valve see how that helps it !

 

[Bradderz_1988]

Also try cleaning the maf sensor with brake cleaner.

 

[pdf11]

i've just seen a egr blanking plate on ebay, i'm ordering one and let you know
thanks for the quick reply
cheers

 

[PAULF]

Try checking the turbo vane actuation - if it is sooted up and sticky, you will overboost and then go into a semi-limp mode.

Mr Muscle fixes this! Un-Sticking Your TDi VNT Turbo Vanes.....

 

[pdf11]

Right.....cleaned maf sensor, de-coked turbo vanes with mr muscle, and blocked off egr valve. 1st and 2nd gear rev fine, but only to 3500rpm. 3rd - 6th still not quick, doesnt seem to be a limp mode just feels lazy getting there compared to 1st and 2nd, but still only revs to 3500, wont go past....running out of ideas as the engine runs sweet as a nut, starts fine, but at the moment its like theres a limiter on it?
any help would be greatly appreciated....
cheers

 

[PAULF]

How about looking for air bubbles in the clear fuel line?
The fuel filter can leak air at the tee-piece, which would be worse under high revs.

 

[aragorn]

Does it rev past 3500rpm in neutral?

 

[pdf11]

thanks for the replys. i'll try both suggestions tomorrow....keep you posted
cheers

 

[pdf11]

hello again!!!
just an update....
checked for air bubbles at tee-piece, i presume thats the part that clips on top of the fuel filter, no bubbles seen after observing for a while, and the car revs to red line in neutral but not in gear, still only 3500. did a trip at weekend at a steady 70-75 and returned 35mpg, doesnt seem too bad, is this reasonable? still doesnt feel quick in 3,4,5,6. the mrs leon 110 tdi is a lot quiker, she's very competitive and is now taking the micky out of my beloved 2.5!!!! lol
any others ideas?....

 

[S4_dan]

have you tried to Scan it with vag-com and see what is coming up?

 

[murran]

revs round the revs in neutral but not under load......... is the advance/****** working in the fuel rotary pump? you need to get it on the diagnostics to check it.

 

[pick master]

Hi thanks for your assistance by PMs
i had a look at cat and mine was clogged up so cut out and now it pull like a train
i drilled a small hole in front and looked in with enderscope then cut pipe before and after cat and fitted a section of pipe
i might need to find a cat for MOT
regards Andy