Omega Owners Forum

Chat Area => General Discussion Area => Topic started by: JamesV6CDX on 08 February 2009, 16:59:20

Title: Diesel engine question
Post by: JamesV6CDX on 08 February 2009, 16:59:20
My 406 TD has always run very cold. I've just stripped out the old stat, and it was well and truly stuck open. I've flushed the cooling system, changed the stat, and re-filled with new coolant - it seems much hotter.

Question - I know on a petrol engine with a coolant temp sensor, that if it's overcooling, the ECU will inject more fuel to compensate - so running cold will affect economy.

How does this work on a diesel such as this one, with everything largely mechanical? Will the engine being up to temp help it's efficiency?

The 406 hasn't been returning great economy lately, but this is partly due to the "leaking leak-off" pipe on injector no2, which halfrauds don't sell else I'd have fixed that too!

Sorry if it's a daft Q - I am not an expert with diesel engines...


Title: Re: Diesel engine question
Post by: JamesV6CDX on 08 February 2009, 17:00:17
Before you suggest a Pug forum - don't - they're crap!
Title: Re: Diesel engine question
Post by: Marks DTM Calib on 08 February 2009, 17:40:04
The same, they dump more fuel (not much)
Title: Re: Diesel engine question
Post by: HGV mechanic on 08 February 2009, 17:51:00
on common rails the ecu holds the injector open for longer, and
(most) direct injection pumps have a cold start timing advance solinoid,
there are various diffrences with different makes of pumps, but you get the idea
Title: Re: Diesel engine question
Post by: Seth on 10 February 2009, 17:04:11
Depends on the system used.

Whatever, a cold-running diesel will consume more fuel than normal.
Ineffective combustion and rapidly-increased general wear - so it's the hotter the better!

New 'stat should cure the problem.