ok.Will do the test today and let you know later on.Thank you

 

Soory my bad i was meaning the Fuel Pressure Regulator Valve (the one which is connected to the pump)is faulty not the fuel sensor(to many things n my had) any way i will do the test with glow plugs today.Thx

 

Done the glow plug test -the light going off after 1.15 second

 

Unless somebody knows/can confirm spec otherwise, I don't believe the time the glow-plug light remains illuminated bears any indication on how long they're receiving power, temperature, etc.

Reason I say this is recently I found I was running with 0 out of 4 glowplugs functioning (causing difficult cold start), but the light went on as normal and goes out after approx 1-2 seconds as normal.
After replacing the glow plugs, exactly the same behaviour, still 1-2 seconds until it goes out, BUT battery draw still seems high after the light goes out which leads me to believe (I've not voltage tested them yet to confirm) that the glow plugs were still receiving power.

 

unless it's really, really cold I wouldn't expect to see much deviation in the time the light is on. Common rail diesels don't need glowplugs as much as older diesels. They will start (not well) without them, whereas on a pre crd engine you were pretty much buggered if the glowplugs failed.

Did you look at the trip computer MPG?

Have you done a leak back test yet?

Richard

 

The trip computer is going down max to 13.8MPG
On the full tank im getting 220miles.

Th injectors are ok an the fuel rail pressure limiting relief valve
has been replaced plus presure sensor on the rail is replaced.

And the diesel consumption is killing me

 

It doesn't.

The light stays on as long as it needs to, to get to a "ready to start" stage.

To do this, it needs to be getting some indication or input, this is temperature related so must be triggered by a sensor.

The past few days, it's been cold here. My light's been staying on for 4-5 seconds when cold, 1-2 seconds when warm.

The glowplugs get power beyond the light. I had a google earlier and it seems this is to help whilst the engine is heating up.

As I mentioned earlier, on VAG cars, pulling the wire to the coolant sensor means the glowplug light stays on longer (10 secs plus in my experience).

 

I've always assumed that the glow plugs, the 55+MPG we used to enjoy in the early 80's, and totally useless eat~your~own~crud valve we call the EGR are interconnected. When we went all CRD and 3kpsi pressure as 'tfb' says our cars would crank without glow plugs. Glow plugs changed from weak and short to 500+°C and long lit, hot in just a few seconds eh! The dreaded emissions laws changed many things including the glow plugs, all those hydrocarbons and nasty and NOx had to be burned quick to reduce the black smoke per crank and the DPF is going to get clogged quick and people won't buy diesels - so when you assume they are off - are they ? - have you measured the input at the glow plug itself for a whole 5 minutes after lights out ?

 

ok, if the trip computer is reading 14mpg then the ECU knows it's putting in extra fuel. This will eliminate leaks, stuck injectors or FCA.

Have you checked for binding brakes? is the gearbox changing up through all the gears?

Really need to get a scan tool and look at the live data from sensors. Look at throttle position, air flow, boost pressure and fuel set point.

Regards
Richard

 

My 2 cts:

My observations are that the colder the engine is (freezing conditions outside) the longer the ligth stays on (like 4-6 seconds).
When I start to quickly (like imediatly) the engine has trouble starting
Under "normal" temperatue conditions the lights are only on for 1-2 secs and engine starts imediatly, no need to wait for glowplugs.

When the engine is already warm but outside temperature is freezing cold the glow lights only light up for 1-2 seconds. So that leads me to believe the length of glow time is determined by a temp sensor in the engine itself.