fuel pressure regulator plumbing

[muddydigger]

ok so on this ere 3.9 the fuel presure regulator is in the sameplace as the 3.5 but the pressure regulator onthe 3.5 has a vacume hose on the back of the plenim chamber, wher does it go on the 3.9?  also ther is on the 3.9 an electronic jigger screwd to the pressure regulator on the 3.5 but not the 3.9 should ther be one?  still having difficulties identifing these two wires left in the new loom.

[Range Rover Blues]

Err, I'm confused by that, we need pictures.

<emawhile on the 3.9 there will be an idles speed stepper motor housing on the back of the plenum, 4 wires go into it.  on the bottom of the mounting plate you will find the vac hose connector for the fuel regulator.

No idea what you mean about the electronic thingy there though.

Where abouts are these wires you can't fit? are they perhaps for the lamda sensors?

[muddydigger]

Thank you now we are getting some where, the steper motor must me the electronic jigger i was refering to on the 3.5 which had two blue wires. the steppper motor for the 3.9 is that black? and i cant sea any wires to it! would they be the whit wand grey and white wires. Apperently the car the engine came out of never had lambada sensors in and the wires are taped up, so im told by the chap i bought the engine from.

[muddydigger]

Ok scrub the that last comment ive found that ther ARE four wires to it and i found the vac hose and thats made a big diffrence to it now it runs a lot better. still no idea about these wires though will put picture on the board later  thnak you so much for sticking with me on this, much appreciated.

[Range Rover Blues]

I'm not so familiar with the 3.5 RFi (often refered to as the 'flapper' system) but it would have had an extra injector I think on the RHS of the plenum.  I don't know about any idle speed valve though.

Can I assume you have a full 3.9 wiring loom to go with the engine? these are pretty much a stand-alone system ie a separate loom so there shouldn'y be any spare wires unless it's for somehting like the charcoal canister which wasn't always fitted.

I'd strongly suggest you try to get a haynes manual as, unlike the Disco, it's actual really useful.

[muddydigger]

I allready have got the Haynes manual, but its not helping me identify these wires. sure it does have awiring diagram, but umnless you know what your looking for on the diagram then its not to much help. Yes i did buy a full wiring loom  with the engine.

[Range Rover Blues]

Oh, cr4p.  The Haynes is where I look when I get asked this sort of thing.

If you have a complete loom for the EFi then all I can say is if it's in that loom, it's for the engine, if it isn't it's not.

Can you be really descriptive or where these wires are, than I can go look at mine (one of which is a 3.9 retro fit too)

BTW, have you started to connect the wires to the main car loom yet, under the clutch pedal?

[muddydigger]

OH Cr*p whats i said too. Yes the engine loom is in the car.The two wies i speek of are a white one and a grey one. they are both into the same conection a black one which is very shiny so it was conected to somethng! they come out of the main loom at the same joint as the earthing points to the engine block, passenger side at manifold height. they both have markins along them but at 4am i cant rember what colour they were. the main loom under the pedal is conected however there is blue conection with has about 3 or 4 wires, that goes no where too. The engine was running last night as sweeet as a nut except it had an occational back fire, after reving reasnably hard,it ran for a good fifteen mins then cut out and wont restart. Testing the wires there appears to be no power supply to the realys main and fuel. If the lambarder sensors wires are red then there appeas to be a tune resistor in them.

[Range Rover Blues]

The tune select rtesistor tell the ECU what tune the engine has and wether there are lambda sensors or not.  There will also be anotheri nt he loom to tell the ECU it's a manaul box, unless you have an auto in which case it needs connecting to the cutout switch on the selector.

2 wires, passenger side, manifold height, black connector.  Right, I'll have a look.

[Range Rover Blues]

Hang on, front LH corner of the engine bay, they might be for the alternator, one is the excitation wire, the other drives the rev counter.

[muddydigger]

Ok mate found why its not working, because i only did a temp conection when i put the loom in and it came appart so no dramas ther its running again. The car is Auto and came from an auto. the rev counter is working and i think the Alternator is as well. The wires are at the back of the engine bay running along the firewall. they come out of the loom at exactly the same point as the earthing wires on the engine block. the back fire is still evident though. not on exceleration but when backing of.

[muddydigger]

Ok i may ahve solved the back fire because ther appeared to ne one to many resistors in the wiring to the coil, one which came in the new loom which i didnt realize was there and the other one which was on the coil(originally) which i left there. so now the car is running, reasnobly well but not perfect. Ill try a new set of plugs as the guy i bought it off said the car had been sitting for a long time. I have had to replace two rockers and rods as they were rooted. The engine doesnt appear to be too bad but i would like it to run aliitle better. Cant say how the fuel is at the moment though it does seem to be a little rich.

[muddydigger]

Eureka!!!! I have identified the wires, they are to purge controle valve. I have gone and bought one and put it on. But has made no diffrence to it running its still a liitle rough and is backfiring any sugggestions ? thanks

[muddydigger]

double Eureka! well im an idiot, I had put two spark plug leads on the wrong way. but have corrected it now. No back fire and plenty of grunt. but rich really rich.

[Range Rover Blues]

Purge control valve? that should be next to the battery on the charcoal cannister.

If it's running rich it may still be in a failure mode, the hot-wire ECU is much more tolerent of faults and has many get-you-home tricks up it's sleeve in the event of a sensore failure.

You have the Haynes right? in the back (the whole bludy car is in the supliments section) there is a dead usefull check-list for the EFi system to sort out if any of the electrical gubbins are not working, have a look through it as unless you have access to Rovacom or similar (mine cost me bucket loads) then it's guesswork to know why it's rich.  You can adjust the mixture with a littl escrew on the back of the mass air flow meter (hot wire) but don't use this to cover up an underlying fault.

2 things it will be sulking about are the lack of a road speed sensor input and not knowing what gear the auto box is in (your original car wouldn't have been connected this way).  The EFi runs fast if the auto box is in drive, the air con is on or the heated front screen.  It also has an output for the electic fans in the event of excess engine temp when running and when stationary plus if the fuel gets too hot when stood.  Wish I'd known this before I wired up my fans.