Evening all! Recently my 05 cargo 1.9 jtd has started having some issues while driving.. here goes while I’m on the motorway and “ normal” driving for me 2000rpm 60-65 mph the engine seems to be misfiring or that I can feel a certain intermittent slight juddering of the engine the Rev counter doesn’t fluctuate but I can definitely feel something amiss.. same kind of pit ken when driving in low gears and approaching the point of gear change. I had a mechanic take a look and said the metering valve in the fuel pump is on its way out.. has anyone else experienced anything like this and more importantly is he trying to pull a fast one and get me to pay for a “ maybe problem” when it could be something else. Other than this van starts and turns over easily and idled without any kind of misfire/judder. Sorry for the essay and thanks for any help in advance?? Time for a beer

Hi,

You wouldn't have a multiecuscan tool lying around by any chance?

John.

Did your mechanic perform any tests on the fuel system?
If not, you're correct in your scepticism.

Modern diesels are complicated things and require a bit more than opening the bonnet, sucking teeth and pointing at expensive parts to diagnose.


Light throttle misfires on steady speed cruises can often be the EGR valve.

The valve tends to work a bit more often when on the above sort of trip as when the engine leans out on a light throttle or over run, the valve opens to allow exhaust gas back into the engine, press the throttle a tad and it should close again.

If it's on it's way out or more likely, clogged up with gunk (soot mixed with engine oil from the crankcase breather) they can stick open choking the engine with exhaust when you apply the gas again, so the engine stutters and shudders.

The best way to test this is to blank the EGR off and test drive it a while, there's plenty of guides about to show you how you do this and it's usually free if you fabricate a blank yourself.

The blank might throw an engine light after a while as emissions control devices have to be linked to the warning systems on certain Euro spec cars, but if it runs ok with the blank, you need a new valve.

murfman53 I don’t have it sorry mate though it is on my list of purchases but there is no engine management lights on at the moment either just the erratic juddering whilst driving.. I have asked about the egr valve and the mechanic has said it’s my driving style and to thrash it from time to time! Well that’s certainly not the answer I was looking for so I’m going to take it to a second garage on wknd and see what they. I will pass both your advice on and thanks again for all your help and advice.??

Hi,

The mechanic suspects it maybe a fuel valve/pump issue. Maybe, at lower revs or idle,

the demand for fuel will be low, and as you increase (speed) the demand will increase

as well. You should feel the engine struggle to reach the desired speed. Lack of fuel,

or the desired amount required. I'd be looking else where for the problem.

Multiecuscan can be downloaded from this site for free, and, you get 20 minutes to

run it before it goes off. You'll only need to buy the cable to plug into your diagnostic

outlet on your Doblo. A couple of pound. You'll then see if the fuel increases with

extra revs. Its an option. We have 3 Doblos within our family and as its been

suggested the EGR valves will give trouble sooner or later. We've checked everyone of

them as soon as we bought them. More often than not, they just needed cleaning

because they do clog up. Error codes will appear, but only when the condition

gets worse. One experience we uncovered was the exhaust gasket can break down

over time, resulting in poor performance across rev ranges although small to detect.

If you see the left hand side of the engine slightly darker above the exhaust manifold

then the gasket maybe the issue. I'd be inclined to go with Goudrons on this one.

It covers most of your problems you're experiencing.

John

Hello!
I would suggest checking the fuel pump for leaks where the hoses connect to the pump... Overtime the rubber bands arround the hoses starts to get tough from the heat and they turn to hard plastic and eventualy they brake and cause leak. Its a cheap procedure to change this rubber rings with silicone rings as they are more resistant to heat... BUT>
if there is no leak from the pump, then you have another problem... possibly EGR valve as the friends above suggested...