zd30 engine rough

[rgw472]

My 2003 d22 started running rough /hunting / missing this morning it seems to run ok over 2000 revs but when it comes back to idle it plays up intermittently it has zd30 new turbo 20000 km ago.. i am thinkung fuel return probs

 

[Old.Tony]

Fuel delivery issues usually affect things in the opposite way, poor fuel delivery doesn't affect idle too much (low flow rates) but compromises higher flow demands.

I'm wondering if the EGR valve is opening too much or is stuck partially open.

Knowing if it's smoking (and what colour) would help - have you noticed any?

I doubt it's turbo related, turbochargers with issues generally don't run well at high rpm and by the sounds of it, yours does.

 

[1310/71]

Is it worth trying the throttle position switch reset?
Someone else may correct me if I'm wrong but it involves letting the car idle for 10mins doesn't it?

 

[Old.Tony]

Sure does. Start her up and go make coffee, read the news, have a slice of toast and do it all while you are making sure some c*nt isn't trying to jump in and steal a car that's been left running!

 

[rgw472]

Drove 18 km back to yard never missed a beat then 12 km home in heavey traffic not a problem I will see how it goes tomorrow thanks

 

[1310/71]

for the time it takes to do it, I would still suggest trying the above even if all seems well.
I'd caution to use a stopwatch or some other timer though, as 10 mins can seem an eternity when you're sitting there watching.