Kangaroo petrol - (Diesel)

[Dan1971]

When just pootling along with even pressure on the accelerator to maintain speed, my Zed has started pinking a little. Jerking a bit ....

What do we think .... ? Fuel filter maybe ....

[peterzs]

Think the pootling is the problem!!

Filter would be my first thought, not let the level get too low and sucked up muck.

Not been using supermarket fuel for to many fill ups, I try and get a good brand BP or Shell in every so often.

I also put in 2 cup fulls of Millers Sports Derv additive, makes it go quicker they reckon.

Know the bleed off pipes can leak, no other air leaks on the derv pipes. Take the cover off and have a quick gander, should show.

Hope you can sort it

[ramdonice]

sounds like a egr valve playing up to me

was the revs around 2k too?

[p_b82]

yeah constant throttle is EGR related me thinks as that is the only time it is activated.

Fuel filter usually gives issues under WOT or heavier loads

[peterzs]

What does the E valve thingy do, the guy that did my engine did have a look at blanking it off, but put it back because of something that I've forgotten.

All made sense at the time, oily fumes come to mind!!!!

[Huffy]

Originally Posted by peterzs

What does the E valve thingy do, the guy that did my engine did have a look at blanking it off, but put it back because of something that I've forgotten.

All made sense at the time, oily fumes come to mind!!!!

It regulated the presuere of the gasses into the exhaust, I have had mixed opinions as to weather it should be used, mines still there.

[p_b82]

it all depends on where you read things...

basically it opens up a port on the exhaust manifold when under constant throttle to re-circulate some of these gases back through the engine... by burning it twice it alters the chemicals coming out the back end....

the downs side of this is that the oil crud builds up in the inlet manifold over time and the engine takes longer to warm up.

the plus side is a faster warm up - as the gases are cooled with a water jacket fed from the coolant system and the car puts less harmful toxins

[Dan1971]

Hmmm ....

OK - I'll do the fuel filter anyway as that's the only thing I didn't do when it was serviced.

What's the score with replacing/blanking the EGR valve then ?

http://cgi.ebay.co.uk/MG-Rover-Diese...item3a6498501a

[p_b82]

blanking plate removes the issues for good... or as you remove it clean the old valve up and refit it....

one is much quicker and less dirty than the other but costs the bit extra

[zsserbia]

Not sure about the EGR... but easy to check. Start the engine when cool and leave it idling for a couple of minutes. When the ecu/egr solenoid opens the valve listen to the engine note (should be the same rpm but sound a bit louder and slightly lower note). If you hear some rattling from the EGR solenoid during the process don't worry about it. What you should hear in 20 seconds or so is the engine note instantly changing back to normal (same rpm but much softer and more quiet/higher engine note). If the valve is stuck and not sealing properly you never get quiet idling or the note changes gradually/not instantly. Anyway, even if the EGR is sticky it wont cause jerky performance you described, just slightly slower acceleration mostly at lower revs and louder engine note.
What I suggest is look elsewhere. First, there is a simple principle about exhaust smoke. If there are loads of black smoke on your tail when accelerating uphill under fool throttle then you have too rich mixture/poor mpg, meaning that something's wrong with boost. if pulling uphill gets jerky at the same time you should check top ic hose. Sometimes even though it looks ok on the outside, the inner layer can brake inside and restrict the airflow. Even when you got a major crack in the hose the engine will run for some time when cruising, then it would start jerking on constant throttle and eventually stall. Again, loads of black smoke are present and engine sounds boomy.
If no smoke on the tail with quiet engine note, mixture is poor meaning you should look for air in the fuel line and/or check the fuel filter. If you hear rattling from the injectors when engine cold and poor starting, then normal after few minutes, you got some air in the system. Park the car somewhere uphill overnight and try to start it in the morning. If fuel line is leaking it would take unusual cranking before it even starts to pick up, but would fire instantly on the first pickup.
If it starts picking up on the first crank but still takes several turns to fire then the fuel filter should be the culprit.
If none of the above makes any sense, try with maf sensor cleaning. If you use an aftermarket air filter which needs to be oiled up, chances are it will eventually contaminate the maf and make it going out of spec. It would affect the performance and cause poor low down torque, also it should cause brick wall rev restriction somewhere between 3800-4000 rpm. Also, you wont get that lovely note at 2500, it will sound a bit dull. So keep your maf clean, especially act quickly if you notice such symptoms.
Also check the #1 injector wiring. Also, your tps sensor may be faulty. To check this, run it in neutral and slowly push the throttle. Engine must not shake in any rev band nor it should run on 3 cylinders on 1200, then again at 1500 etc... Definitely go for diagnostics check on this one.
If all of the above is ok listen for any "transit effect" in the engine note coming from the injectors. If this is occasion, to verify which injector is faulty grab a screwdriver and push it against no.1 injector. The other end you should hold against your ear and listen for any irregularities in injection timing in comparison to other injectors when engine is idling. Repeat the process with each of the injectors and you will easily find the one which doesn't work same as others. If it is single injector missfiring you have a local problem with one of the injectors, but if the "transit effect" is applied to all of them, chances are your fuel pump timing solenoid is faulty or even the pump is dying. If this occurs when engine is hot stop by to the fuel station for a refill. Your VP30 fuel pump needs at least 3-4 gallons of fuel in the tank to cool itself properly because 80% of fuel circulation is used for cooling the pump and only 20% is smoked...

There ya go mate, hope this helps. Anyway, if you solved your problem already hope you will keep this for future reference and share it with the others...

Cheers