Range Rover 2.5 Glow Plug Cycle

Theanswers

Hi,
I would like to increase the time the glow plugs stay on in my range Rover 2.5 Diesel.

Would I change the relay to do this?
Thanks,
Peter

101sean

No, they are timed by the engine ECU and is set by by the ambient temp, coolant temp etc. You can't alter it. I assume we are talking P38 with the BMW engine?

Fishtits

For why you want to do this?

more to the point...

Theanswers

The reason why I want to increase the glow plug cycle is because I run her on Vegetable oil which sometimes can cause it to be difficult to start on cold mornings. I run on up to 90% Veg/ 10% Petrol.

I'm thinking of maybe increase the amount of petrol to attempt to compensate.
I have installed a fuel preheater and have a heat pad, however this only works when I'm home and near a socket.

If the glow plugs stayed on longer she's be easier to start.
Now I usually pre heat them a number of times. However switching on the preheater before starting the car does drain the battery and I can notice it get sluggish now, Its only 6 months old.

101sean

Common rail diesels don't need any pre heat to start unless you're getting down well below freezing (when on diesel!). As they are controlled by the ECU, you turning them on several times is just wasting battery.

Theanswers

101sean wrote: »

Common rail diesels don't need any pre heat to start unless you're getting down well below freezing (when on diesel!). As they are controlled by the ECU, you turning them on several times is just wasting battery.

I'm not sure do I agree with you on that one Sean. She seems to start better with at least three preheat compared to just one.

With one she more the likely will fail to start.

Is this just my imagination?

101sean

They could be getting successively hotter each time I suppose?

Have you tried a search on BMW or P38 forums, the same basic engine was in the 525?

rrv8

You can fool the P38 diesel into bringing on the glow plugs for longer by fitting a timer relay to switch in resistors , fooling the input sensor to the heater timer to think the engine is colder than it really is BUT all it does is eat glow plugs as they are being heated for too long and simple burn out
Main thing with cold starting on the P38 diesel is the battery , hard to get a decent battery these days , on mine it had a new battery every year for the past 3 years , luckely all under warranty , first frost and there down on cca .Also make sure it has a minimum CCA of 750 amp , plenty of cheaper batteries only offer 600 CCA

Fishtits

Your Range Rover has problems that will not be solved by extended pre-heat times.

IMHO of course...