TD5 no power after 60mph

hi all,

since last week my discovery is loosing power after about 60mph.

If you put your foot down to the floor from start the revs go right up and she shifts quickly, but then at between 50mph and 60mph the revs drop of and the van just stitts there doing nothing. If i press the sport mode button the van will go up to 65mph. Also if it hits a hill the power keeps falling, even when your foot is right down.

You hear the engine working away, just not getting the power?

i have changed the boost control and new air filter, but nothing changed.

i nead the discovery for towing, but the way it is i cant

any help on this

its a td5 auto, egr removed

thank you

john

Have you checked the oil level on the auto box . Just in case your losing the power /drive . That way

A quick test to rule out box if ya don't want to get under it and oily is find a slight incline and pop it in D or 1st and see if she holds or try's to move . This is even a good little test on the flat to they alway should try to creep forward .

i would change the fuel filter and check fuel pressure regulator for leaks . also fuel pump may be on the way out, is the pump noisy?

Assuming I had access to a diagnostic (which I do!) I would be checking the MAF (Mass Air-Flow meter) to ensure it is working correctly.

If you don't have access to a diagnostic, take the car for a drive on a road you know well which includes up-hill work and carefully metally monitor what happens - then go back to base.

Now unclip the MAF electrical connector and do exactly the same route again and note what happens. If there is no difference then either the wiring to the MAF is faulty or the unit itself.

Another sensor to check is the MAP (Manifold Absolute Pressure) which can be found on the inlet manifold (remove the large plastic engine cover first to give access).

Take this sensor out and examine it, it is probably caked in a tar-like substance which stops it working correctly. Clean with an aerosol can of Brake & Clutch cleaner, allow to dry and re-install. Now test the car again.


Other may argue but I've bought several cheap Ebay MAF's and fitted them to a number of TD5's and all have worked well, giving the correct readings etc.

Cost about £30 so why not do it?

Good luck

Dave

after reading your comments, and some more reading online , i done the following to day

check that the wategate was moving yes moving ok
took sensor off inlet manifold and claened had a bit of sludge
removed the electrical connector from the bottom of the modulator
disconnected the battery and left for 5 mins then reconnect
check that the egr blue hose was blocked off yes it was
auto box test : (done in 1,2,3 and D )
on level creep forward
on slight slope creep forward
on big incline nothing, but even a slight touch on the pedal it would move forward
fuel pressure regulator was done last year, but will order a new one, same with fuel filter.
fuel pump is not noisy at all

I then took it for a 12 mile test drive, it was fine revs when up and pulled away over 70 , yes i thought. but 2 miles from home it whent again no power when you put your foot down . It was like that for 1 mile, then all the prower came back

any ideas what it could be ?

could it be the sludge on the sensor?

thanks

So it's speed related rather than power related? I'm just thinking of turbo overboost protection kicking in which is usually cased by a split in the wastegate modulator hoses (favouite one is the one comming off the metal air/turbo pipe)
Griff