Leak-off testing on Picasso HDi

steviewonder7 · Unread post by **steviewonder7** » 09 Jun 2011, 19:15

Hi Folks,
Need some advice from those in the know please.
My Picasso only just passed the m.o.t the other day,it just and i mean just passed the 'smoke test'.Always wondered why my fuel consumption was a little down on what I expected it to be,plus the tailpipe being rather black.

One of the mechanics at the m.o.t station suggested i may have a dripping fuel injector or two or three.Would this be the case? Could it be anything else? I thought it might be the MAF sensor playing up giving the ECU wrong info,but the mechanic said it doesn't work that way on diesel's.

If it is the fuel injector(s) playing up/leaking would it be wise to do a 'leak-off' test for the injectors,hopefully pinpointing a faulty injector?
If so how do you go about doing this on these HDI engines?
Any thoughts on the matter chaps?

Regards Steve

wheeler · Unread post by **wheeler** » 09 Jun 2011, 19:44

A leak off test wont show a dribbling injector like the mechanic is talking about. When a leak off test is talked about on an HDi engine you are checking the return flow rate of the injectors, if too much fuel is returning then not enough is getting to the engine & the system will not hold enough pressure. This would be more likely to cause difficult starting rather than excessive smoke.

steviewonder7 · Unread post by **steviewonder7** » 10 Jun 2011, 12:48

Thanks for your reply Wheeler,

How do I go about checking which injector(s) is playing up if the leak-off test doesn't give an indication of a poorly functioning injector.Is there another test that can be carried out by myself or am I looking at the requirement of more professional help ?

How much,roughly speaking are new or refurbished injectors nowadays?

If I have to I dont really want to send off my injectors to be reburbished (providing the price is not prohibitive) as I need the vehicle all the time (with my partner dying of cancer and only having weeks to live).

Your's seeking more advice Steve

Unread post by **myglaren** » 10 Jun 2011, 16:20

Sorry to hear of your partner's terminal illness. Makes your car problems all the more fraught.
Ideally, get your codes read and cleared then the live data read on a Lexia, which will give an excellent indication of the state of injectors.

Look here for a member with a Lexia close to you that will run a diagnostic for you.

Injector prices seem to be linked to the engine fitted. Mine for a 2.0 HDi are £250 (dealer price), may be cheaper sources though Bosch and Delphi diesel centres are worth a look.
I have found some on eBay for £185 each but need to confirm that they are correct.

steviewonder7 · Unread post by **steviewonder7** » 11 Jun 2011, 12:50

Thanks for your reply Myglaren,will look into the problem a tad more when i can.

Unread post by **myglaren** » 11 Jun 2011, 13:42

Not much of a reply but I hope it helps you to decide what is required.
I will add to this when I get my own injectors seen to.

May be some time as it is chucking it down, all the excuse I need not to grovel around under the bonnet - or be cutting grass.

Xantidote · Unread post by **Xantidote** » 12 Jun 2011, 11:47

If you have a diesel specialist in your area, they may be willing to test the injectors for free, assuming you've removed them. I've had injectors tested on 2 occassions in the past. They were older style injectors (1 set off a BX turboD). I think they just checked the pressure they operate at (?), and the spray pattern.

They probably do this on the basis that if any work is to be done, then they'll get the business.

steviewonder7 · Unread post by **steviewonder7** » 12 Jun 2011, 14:38

Xantidote....I will be looking locally for such people to see what they say..if there are any in my area that is.Thanks for the thought.