Advice please

1996 405 LX td intercooler, (XUD) engine
this car seems to be lacking in boost when under 2500 rpm,
but when over 2500 rpm its ok,

I have fitted a second hand fuel pump from a 1993/4 405TD,
due to internal failure of the original Lucas pump,
The original pump, performed very well and the turbo boosted equally well,
Any Ideas,
Any tuning tips,
Thanks
Fitzy

 

Hi,

Perhaps it is an incorrect pump avance setup (almost nothing, as you mean
the engine runs pretty good).

You could perform a boost pressure test, too. Unfortunately I haven't the
values here (I remember I posted them a while ago), I just remember it
should be around .95 bar but no idea for the revs.

 

Thanks GT,
I have decided to start adjusting the dump valve adjustment rod,
small increments at a time until the boost from the turbo comes in at a
lower rev, something like 1800 - 2000 rpm would be perfect for me,
I will let you know what the outcome is,

Fitzy

 

on the 306 the boost comes in at 2200 and is 15 psi