Nope, tank outlet at top...Red won't like that!

Put electric pump in the boot today.

 

Electric pump pushing to the stock mechanical = slight improvement, wherein in doesn't lean out quite as much, but still does.

 

Electric pump only = identical symptoms to mechanical only.

 

Electric pump gets considerably noisier during the lean events.

 

Maybe the tank is full of crud, which blocks the pick-up sock when sloshed around, but drops out of suspension after sitting for a while?

Electric pump gets considerably noisier during the lean events.

 

Sounds like that is definately involved. Dad had a leaf (he reckons) in the tank that periodically blocked the intake and the car died, but by the time you stopped the motor was off , the suction gone and the leaf floated away, so it re-started fine.

 

Pop the fuel level gauge plate out of the tank and shine a torch in to see what the fuel pickup tube looks like.

Tank vacuum?

Definitely not vacuum in the tank. This was the first thing I checked. Vented cap...leaks like a sieve on hard corners ;)

 

Okay, pulling the pick-up out tomorrow! (Weather & hangover not withstanding, LOL)

Well, well...so it WAS the EGR valve after all!

 

Pulled it off & bunged the manifold with a suitable sump plug on the weekend & drove it today.

 

Idle & off-idle hesitation issues GONE!