On Tue, 21 Dec 2010 09:06:27 -0000, R C Nesbit > wrote:

>The 156[1] has been a nightmare for the past month or more,

You are a masochist.

>with a ritual of parking nose in under the car port for the
>night with the battery charger plugged in,

So, either the battery is gubbed or the alternator is gubbed or the
car isn't getting a long enough drive when you do get it going?

>and using a heat
>gun over the fuel lines and into the air intake, still
>taking at least 5 or 6 attempts to get it to fire.

Unless you've not got winter diesel in there, heating the fuel lines
won't make any difference. If it did, then the diesel is waxing up and
the car will *never* start let alone run properly. UK winter diesel is
well up to the task of the current UK temps.

>The past 2 mornings, however, were possibly the coldest
>it's been so far, and it started first click!

>Notably the glow plug light seemed to stay on longer, and
>it ticked over at 1k for a while, whereas previously
>tickover was below 1k

Sounds normal.

>Is it possible that the temp sensor is faulty?

Possibly but, more likely IMHO, the glow plugs are past their best and
have gone higher resistance than they were when new. The longer
heating time of the maximum cold start mode has allowed them to warm
up enough to do the job.

The car (in UK unheated block spec) probably will not turn over below
about -20C (which is likely to be about the freezing point of average
coolant anyway) so below -5 to -10 ish (depending) the car will go
into its maximum cold start mode (longest pre-heat and increased
idle).

I never abused my Alfa like you're doing so I don't know if it'll do
this but, it may be possible to do multiple pre-heat sessions. Try
waiting until the glow plug light goes out then (quickly before losing
heat) turn off the ignition and on again and wait for the glow plug
light to go out. Repeat so you get 2-3 heating cycles then on the last
one after the glow plug light goes out, fire up the engine. It's an
old trick and it may not work - don't do it more than 2-3 times
because if it doesn't work at that then it probably won't work at all.

Look, it's not that complicated. Take it to an Indy and get *all* the
glow plugs replaced. Don't do it yourself unless you're mechanically
capable of getting a glow plug out that shears off at (or below!) the
block surface.

--
Z
Scotland
Alfa Romeo 156 2.4JTD Veloce Leather (sold)
'Oil' be seeing you..
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