V6 stalling/poor running

[stuvaux]

cheers mark

i'll go and try it now

stu

[stuvaux]

it does seem to smooth back out after hitting EGR
could that be the problem then?

stu

[Marks DTM Calib]

Ok...remove the EGR valve (two torx headed bolts) and make a plate the same shape as the EGR base from a tin can or pepsi/coke can (these are easier to use as you can cut it with scissors, careful though, its sharp) and use this (along with the origainal gasket, place the gasket on the bottom of the stack so you haev gasket, blanking plate and EGR valve) to blank the EGR off..(you only need to put two holes in the blanking plate for the securing screws, no others are required).

If it works, speak to Issunaz and get one of his high quality blanking plates...

[stuvaux]

ok  thanks mark

i'll do that mate
would it be better later on to buy a new EGR valve, or just blank it off better?

stu

[Marks DTM Calib]

Blank it off and forget it was ever there...its only required for initial approvals and not part of any MOT test.....help the throttle response slightly to following constant speed cruising.

It does still need the electrical connection to keep the ecu happy.

[stuvaux]

ok thanks mate

i just hope this finally does cure it!!!

i'll let you know how i get on

thanks again,   stu

[Marks DTM Calib]

Worth adding my theory for completeness.

The EGR allows the ECU to add an inert gas (in this case exhaust fumes because in theory there is no oxygen or fuel) into the inlet system. This in turn dilutes the air/fuel mix, this can be considered as alomst a way of reducing the cc of the engine and as a result less heat is produced during the combustion cycle. This in turn reduces NOx..... (it does not affect engine temp significantly or efficiency as you still need the same fuel air mix to produce the required power)

This valve only opens at part throttle and constant speed driving (its variable via PWM to allow different openings to be supported with feedback to the ECU on its position).

Its should not be open at all at idel or full throttle.

If it is open at idle it causes poor running because it dilutes the fuel/air mix to much...(there i very little any way at idle!).

Given that it is a solenoid it is possible for it to get stuck (possibly due to carbon build up) hence why hitting it can cause it to pop shut again and you get an intermittent poor idle.....

Lets hope a 40p drinks can fixes it for you!

[stuvaux]

thanks for the explanation mark

reading that makes it sound very possible that it is the problem
i'm just waiting for my brother now to bring the right torx bit, then i'll get on with it

oh, and it will be from a 60p beer can.........

thanks ,   stu

[Marks DTM Calib]

oh, and it will be from a 60p beer can.........

A fine choice.....I approve!  

[stuvaux]

thank you...

i've fitted the blanking `plate` now
car seems to run fine....just have to wait and see how long for
it seems to just keep coming back......!

thanks mark,

stu   8-)

[Marks DTM Calib]

If nothing else, it rules it out of the equation....

[stuvaux]

i guess that rules it out then....

it started again last night......

the instant consumption goes to around 0.8 gal/hr instead of the usual 0.2/0.3 gal/hr at tickover if thats any help
also the exhaust smells of bad eggs, though i suppose this is because of too much fuel/not enough air in the mix

any more ideas mark?

thanks,  stu

[Marks DTM Calib]

Any recorded fault codes?

Is it doing in this on LPG or Petrol or both....

[stuvaux]

the problem is there on both lpg and petrol

the fault codes are 19 & 135, but i changed the crank sensor and that has made no difference

stu

[Marks DTM Calib]

Idle valve is seated nice and tightly in the plenum, no hissing noise evident from anywhere?

Any recent work carried out?