Signum cdti idle/temp problems

[Kar54]

Hi All,
i'm new to this forum and was wondering if anyone could shed light on an issue i'm having with my Signum (1.9 CDTi).

I've read through the stickies and some issues there seem similar to the symptoms i'm having but the two problems i'm having may or may not be related...

The car seems to idle erratically after its been on a run - jumps between idle and 1000rpm and kicks out quite a bit of smoke which is kind of bluish but smells of diesel to me. It almost sounds as if the turbo kicks in for a split second as well when it jumps to 1000 rpm. However if i turn i off then start it again it idles perfectly - no smoke, no smell. The spanner light is also on permanently.

another issue is the temp guage - which may or may not be related. it barely moves from 70. tonight i stated it, let it idle and it went to 90. when i moved off it then quickly went back down to 70 (along with idle issue until i pulled over and re-stared the engine.) is this related or a different issue?

any help greatly appreciated :-)

[Kar54]

bump ;-)

[the-wizard]

To start the thermostat is a very common fault, Ive just done mine its a bit fiddly but anyone a bit handy can do it, their about £35-38 from ebay(there is a guide in the 'how 2' section), You really need that fault light code read (im sure there must be other members in your area), The stored code will give you a better idea of whats wrong.

[paulvectrac]

I wonder if its dpf proble also as the wizard said new stat but the erratic idle could be a number of things

[Kar54]

Hi,
thanks for the feedback everyone. been doing some trouble shouting today and driving around the site at work:
Disconnected MAF started ok then went into limp mode (barely got over 1000rpm), pulled over and the erratic idle and boost problems still there.

Reconnected and then disconnected the MAP. Car at stable idle at all times, no smoke, but maxes out at 3000rpm so very slooooow. Understandably, this has now put the engine management light on.

I drove it home like this to avoid having to pull over every 5 mins to turn the ignition on and off, but not sure if not having a MAP sensor connected will damage the engine(?) i also noticed that the temp when up to 80 and stayed there (although as wizard mentioned, its probably goosed.

Will carry on investigating

[Kar54]

Hi,
i've had the diagnostic report back now and it has thrown back a few errors:

P0100 IAT Signal Too large
P0105 Boost Pressure Sensor
P0110 Charge - Air Temp sensor signal too large
P1901 Particulate Filter Pressure Sensor Malfunction
P1900 Particulate filter regeneration not complete.

Now, i can see one of them relates to the MAP sensor (P0105, i think) nut i'm not sure what parts the rest of the codes relate to or how easy they are to do (particularly regarding the DPF), so any more help here appreciated :-)