Thanks to all who've replied so far.
I'm tempted to go for the Argos one since if it doesn't work they'll take it
back - I didn't define what I meant by low cost - just not Renault's
full 'testbook' or whatever they call it! The 100 quid version seems to be
a better buy as it does 'live' data?
When I'm saying it goes to LOS, it has the symptoms of that (see below), but
no dash warning light (bulb is working!).
I've been having a good look at things. The engine 'sounds' fine and
smooth - smooth is funny term for a Renault dTi but hopefully YKWIM! Engine
appears to be limited to just over 3000rpm, and under load runs out of
breath before that - clearly no turbo happening. Last night removing
battery power for a while would restore normal engine behaviour, until
driven for a short while. It MAY well have been after some boost that this
happened, but it now seems to be stuck in the 'limited' state.
I'm trying to use Haynes 3395 for this, but it doesn't seem good for the F9Q
engine,in particular. I'm not seeing a lot of evidence of vacuum activity
within the engine, but the brakes seem fine, so am going to look at this
next. An intermittant problem doesn't suggest that a hose has come off, but
I suppose there could be a split somewhere? The normal 'sigh' noise you
hear on switching off is not happening.
Turbo actuator - I assume this is the wastegate actuator on the dTi? Is it
vacuum powered via a solenoid? How would I test it (fault code reader?!)
Access looks a little awkward as it's round the back of the engine under
the dashboard - remove air hoses, I assume?
OK, no splits that I can find in the vacuum hoses. There is a large bore
hose and a very small one coming from the camshaft driven vacuum pump. if I
clamp the main hose with pliers, and remove the small hose (which goes to
the EGR solenoid), I don't feel much if any vacuum when I block the small
hose with my finger - should I? Haynes; "As a guide, after one minute, a
minimum of 500 mm Hg should be recorded." at idle with a gauge on the main
Is it reasonable to conclude that the pump is the culprit, or could there be
With the engine running, you should feel noticable vacuum on the end of the
pipe from the pump, but a leaking brake servo could also be the cause.
Easiest way to check, is feel how much vacuum you get at the small pipe with
the servo connected, then disconnect the main pipe from the servo. Block the
big pipe with one finger, then feel how much vacuum you get on the small
pipe. If you get noticeably more on the small pipe, then the servo is the
Of course, the proper way to check would be using a vacuum gauge.
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