Engine is actually in a Pug Boxer van, but its the same as any other application, its a 2.0 . The van starts and runs fine, but after a little heat is in the engine , lets say 2 miles, if you take it up to 3000 rpm ish, the engine rattles really badly as if it has dropped a valve
If you gradually let the revs drop off, the noise goes away, and a little smoke may be emitted, perhaps unburnt fuel, it certainly smells a tad rich. The more you do this the worse it gets,it will even completely stop sometimes, but if you drive steady at no more than 2500 rpm its fine. The Lexia seems to lag a little on this vehicle, ie about a 1 second delay on parameter readings, but I have noticed (no fault codes by the way) that when the crucial noise appears, the pre injection advance works its way up to 32 degrees and then switches immediately to zero. I wonder if this is related or the ecu is just doing that because it senses a problem.
This is the only thing I can find, fault wise.
So far the van has had,
High pressure pump (changed under warranty because the 6 month old one was leaking)
Injectors (one at a time with used, but no difference detected)
Crank sensor
Cam sensor
Oil changed (was possibly a little overfull, made no difference)
Checked valve springs for breaks ( not 100 % they are ok but reasonably sure)
Drained all fuel, and replaced ( possible petrol contamination)
Air flap in the intake manifold removed about 1 yr ago.
Non of these things has made a deal of difference, any ideas, I am pretty flummoxed now, so all suggestions gratefully received.
