Routing pipes from the injector block to the inlet manifold

[disco kid]

Disco II V8 2002 .. pre headlight change

I have a suspicion that the pipes from the injector blocks to the inlet manifold on my Zavoli system may be incorrect .. the motor has just been in for an exhaust replacement and I am getting intermittent misfire and O2 sensor codes.

I have a vaque recall of being told (but never looked ) that from eachset of injectors 2 pipes shoul stay on the same side as the block and two should cross the valley to the other ..

is this so, and if so just exactly how should they be routed .. currently all pipes cross the valley to the other block. I've photo of the general under bonnet layout in case it helps
Thanks

[rossko]

currently all pipes cross the valley to the other block

That's not a problem in itself, that's what I do.
BUT
yes the cylinder tracts are not in the order they appear, so the installer needs to take great care to get the wiring crossed up correctly.
It all depends on how the gas sytem is connected to the petrol injectors, which can't be guaranteed in any particular form, but say the petrol connectiosn were
FRONT
A E
B F
C G
D H
then the corresponding gas injectors to suit your install would be
E A
B F
C G
H D

EDIT - I see you have Matrix injector rails, which don't lend themselves to cross-connections having just one big plug. That can still be okay, IF the installer crossed up the petrol injector end so as to have the same swapping effect.

[disco kid]

Thanks for getting back to my post ..

I think you are saying that the routing is dependant on the installer's decisions rather than a manufacturers specification ..

I know 'things' do affect the running .. when I got the motor I was getting, intermittently, P1129 codes saying the rear Lambda sensors were swapped over .. it seems that in fact, at some time previously, the electrical connectors to the injectors had been swapped .. which is why you can see, in the photo, the left hand connector is marked with red tape.

I recall that the inlet manifolds, despite their appearance, do notfeed all the cylinders on that side, but I cant recall how they do actually feed ..

I guess I'll have to get someone to look at it (I admit to not being the sharpest knife in the chef's block)

(thinks ....) bearing in mind that it was running reasonably OK (some of the time) with the timing completely screwed, I could swap them around and probably no harm would come to the beast?

edit ..

I guess they are as intended .. I swapped the middle pairs over and it came up straight away with P1129 .....
Back to the drawing board ..

Thanks for your input anyway

[rossko]

Each injector in my picture is numbered with the engine cylinder it feeds.

Oxygen sensors are actually quite delicate, if this exhaust work involved a bit of hammering one or more may be bust or more likely partially bust (weak signal).

[disco kid]

OK Rossko, thanks ..

It's booked in to be looked at next week .. It is plumbed as your picture .. so something else is causing the misfires
Cheers