C30 Engine : C30 Reduced Engine Performance - Again!

[XC90Mk1]

Glow plugs don’t function like spark plugs. All they do is get really really hot when you first open your drivers door to preheat the engine.

Accordingly if the car goes to reduced power on startup this may be the issue. If however the car goes into limp mode after a while I doubt it’s glow plug related. After a short time (maybe seconds?) the glow plugs are not in operation.

Is there a relay for the glow plugs? If their is I would order a replacement and swap that first. Relays are very inexpensive and simple to fit.

[VolvoRob38]

Originally Posted by XC90Mk1

Glow plugs don’t function like spark plugs. All they do is get really really hot when you first open your drivers door to preheat the engine.

Accordingly if the car goes to reduced power on startup this may be the issue. If however the car goes into limp mode after a while I doubt it’s glow plug related. After a short time (maybe seconds?) the glow plugs are not in operation.

Is there a relay for the glow plugs? If their is I would order a replacement and swap that first. Relays are very inexpensive and simple to fit.

This is interesting...

I didnt know that the glow plugs kick in when I open the drivers door to warm up the engine. Is this always happening even when I open the door briefly to get something Ive left inside, without sitting in the drivers seat?

When checking the hidden menu on the dash I do have a few items on DTC SET, one of which is DDM (driver door module). I wonder if this could be related. That has been there for many months, I just assumed it was something to do with a door air bag or something.

There is a relay, which is what vida is saying ECM 6620, but its behind the nearside wheel arch. I was going to try cleaning it with some contact cleaner first, if I have to get at the ECM. But hoping its glow plugs because easier lol.

[Batlamb]

Originally Posted by VolvoRob38

Oh I see... did you have a glow plug error code/message come up on the dash? Or the Reduced Engine Performance message?

Thanks

Yeah. Best just to take it to a specialist.