Lumpy running tdi 300

Hi all,

My Disco has started running rough and sluggish (a bit like a petrol engine with a fouled plug). Very lumpy tick over and white smoke.

Slackened injector unions one by one, and each time running got rougher on each except number 2 - which displays frothing diesel. Removed very soggy injector. gave good clean and put back - but no improvement.

Have seen similar thread, where new injector bought and no improvement - so a little reticent to rush out and buy a new one in case the problem lies elsewhere.

Has anyone come across similar symptoms?

THANKS.

Not seen the thread you talk about but white smoke from a diesel usually means unburnt fuel from what I've been told (although others on here will know a lot more about it than I)

The symptoms you describe would say to me that it's miss firing on #2 but I'm not a mechanic.

Have you checked the #2 union on the injector pump? Could there be an air leak in the pipe anywhere? Could the pipe be blocked?

You could maybe remove the union completely and see if flow is restricted in comparison to the other lines.

Lots of things to look for before you go spending money!

Hi & Thanks for that. Just discovered a new injector comes in at £223 + Vat - so, I'll be looking at all possibilities. Thoughts were turning to head gasket, although having cleaned the #2 injector (and after a few miles this afternoon) the white smoke has diminished and engine seems to be running a little smoother. It may be that after cleaning the #2 injector - a tiny bit of crud was left that has now subsequently been 'Blown out'

Anyway, fingers crossed!

Cheers,

Roger

At least you know its injector related now (well you can be reasonably sure).

by the way....223 quid? Is that an EDC injector or something... 300tdi injectors are £72 from mm4x4.

rogerowen said:

Hi all,

My Disco has started running rough and sluggish (a bit like a petrol engine with a fouled plug). Very lumpy tick over and white smoke.

Slackened injector unions one by one, and each time running got rougher on each except number 2 - which displays frothing diesel. Removed very soggy injector. gave good clean and put back - but no improvement.

Have seen similar thread, where new injector bought and no improvement - so a little reticent to rush out and buy a new one in case the problem lies elsewhere.

Has anyone come across similar symptoms?

THANKS.

Click to expand...

What fewell ar u usenn?

This happened to me when air was getting in the system.
Start from the injector pump,work your way back to the sender unit in the tank.
Mine was a sender unit,the 2 pipes coming from the sender on the top were rusty porous.
Ended up with new lift pump sender unit and pipes front to rear.
Bout 150 quids worth.
So if it is air it could be in a number of different places.

Unusual that air from the tank would decide to exit at only number two injector. I would swap the injector for one of the other three and see if the problem moved to that swapped unit.

If so change the injector, if not and the air is is coming out of a single injector pipe then it is possible there is a fault in the pump or the the unions or pipe (between pump and injector). To be honest the pump delivers fuel at such a high pressure if the unions were damaged or the pipe split there would be leaking the fuel from that particular point, be careful of diesel spray, it atomises the fuel so finely it can penetrate the skin and prove to be real bad for your health!!

To eliminate the tank and piping I stand a gallon of diesel on the roof (of the car and not your shed) and gravity feed the INJECTION pump not the lift pump, if all runs well then start to look at the other side of the system (cheaper than an injector pump).

Hope that helps

regards

Dave