wee_arthur Posted April 23, 2011 Share Posted April 23, 2011 Hi there, I have recently acquired a 1995 range rover with a 3.9 injection and the engine is now in my 90. The starting problem happened when it was in the range rover and i thought it was the ignition side. However after putting it in my defender the service was done but now after further investigation caused by a lack of a running v8 there is no voltage at the injectors. What would cause this? The range rover was running fine one day and then the next it just kept turning without attempting to fire. A few places i have checked so far: fuel is being delivered by the fuel pump "-ve" to coil is definately in place. The 3 amp fuse had blown under the seat but it was replaced, what would cause this? To the best of my knowledge the main relay is operating correctly. Any ideas would be greatly appreciated. Thanks Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted April 23, 2011 Share Posted April 23, 2011 I thought the main relay only powered the injectors/FP once it saw the engine turning/sucking air (coil pulses + afm signal), I'd check your wiring - full diagrams in the tech archive. Quote Link to comment Share on other sites More sharing options...
wee_arthur Posted April 23, 2011 Author Share Posted April 23, 2011 I have just been in the garage doing the instruction on the diagnotic manual and i get 12v out of the relay at all time ? :S Dodgy relay, or dodgy wiring. Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted April 23, 2011 Share Posted April 23, 2011 Which relay, which pin? From memory one of them is a twin-pole 87/87 (not 87/87a) type. If you've got 12v all the time at the relay and 12v none of the time at the injectors then it's going missing somewhere. Quote Link to comment Share on other sites More sharing options...
wee_arthur Posted April 23, 2011 Author Share Posted April 23, 2011 Hi fridge, Do you know where i would get the wiring diagram for a 1995 EFI unit. The others all have 7 wires on the main connector plug, whereas i have 7 on my loom. I fear a mix up in the ages has happened I used a 1991 will this be the same diagram do you think? Thanks again, im getting there Quote Link to comment Share on other sites More sharing options...
Range Rover Blues Posted April 23, 2011 Share Posted April 23, 2011 The 1991 wiring diagram is in the Haynes and the one posted on the internet all the time, it should have the lambda sensors on it. I've never seen the diagram for the 1995 soft dash, the ECU is under the dash and I don't know if the loom is stand-alone like on the hard dash. The earlier loom didn't have lambdas (I've seen these fitted to 1990 and '91 cars) but the 1988 loom used different colours, this was for the analogue hot-wire though it uses the same ECU plug and pinout so can be substituted. I don't have the diagram to hand but aren't the injectors earth-switched? Is the MAF connected? and the lambdas? without at least one if not both it probably won't start. Worth checking because mine did exacly the same when the MAF was failing until it let go completely. I didn't realise it was that until I'd been towed home, with lambdas you can run limp-home with the maf disconnected once it has failed. And oddly I saw the check engine light for the first time in 5 years after swapping the battery so don't expect that to let you know if anything is wrong. Quote Link to comment Share on other sites More sharing options...
stuck Posted April 24, 2011 Share Posted April 24, 2011 I had this problem on my CCV motor, worked through the EFI drawing and in the end found the following: On relay 87A you will see two pins with brown wires with an orange tracer, according to the drawing these should be connected together but on mine they weren't for some reason, connected them together with a shorting link and she fires up every time, take the link out and she won't fire at all, no idea why the pins weren't connected together though... HTH's Mick. Quote Link to comment Share on other sites More sharing options...
wee_arthur Posted April 24, 2011 Author Share Posted April 24, 2011 I had this problem on my CCV motor, worked through the EFI drawing and in the end found the following: On relay 87A you will see two pins with brown wires with an orange tracer, according to the drawing these should be connected together but on mine they weren't for some reason, connected them together with a shorting link and she fires up every time, take the link out and she won't fire at all, no idea why the pins weren't connected together though... HTH's Mick. Hi Mick, what relay is this? Do you still have the wiring diagram you used thanks. Quote Link to comment Share on other sites More sharing options...
stuck Posted April 24, 2011 Share Posted April 24, 2011 It's the relay that switches the injectors. The wiring diagram I used was out of a book of lies but I think the same one is available in the tech archive on here, if you can't find one PM me your email address and I'll scan it for you. Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted April 24, 2011 Share Posted April 24, 2011 This any help? Quote Link to comment Share on other sites More sharing options...
Hybrid_From_Hell Posted April 24, 2011 Share Posted April 24, 2011 or these http://forums.lr4x4.com/index.php?showtopic=16476 Nige Quote Link to comment Share on other sites More sharing options...
stuck Posted April 24, 2011 Share Posted April 24, 2011 That's the puppy. My problem was on the relay designated as number 22, if you look at pins 87 & 87A they should be internally connected, mine weren't for some reason. Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted April 24, 2011 Share Posted April 24, 2011 *most* automotive relays don't have the extra pin, and those that are 5-pin are usually changeover type, so if someone's swapped it before with a "standard" part that may well be to blame. I think the diagram is correct, in that the extra changeover pin is 87a and the extra double-make pin is just called 87. Quote Link to comment Share on other sites More sharing options...
wee_arthur Posted April 24, 2011 Author Share Posted April 24, 2011 Okay so i have diagnosed that both relays are "kaput" so bought another couple and will check the resistance between pin 87 and 87a to see if they are internally connected. I also discovered that i accidentally misplaced the fuse output as a fuse input to the fuel pump via the fuse. So this would cause the relays to blow So hopefully after these new relays are in i hope the main relay and fuel relay will work, and voila hopefully. Thats my theory. Will get back to hopefully spread good news. Quote Link to comment Share on other sites More sharing options...
wee_arthur Posted April 25, 2011 Author Share Posted April 25, 2011 Okay so a little update, I now have both relays fully functional and in the proper setup. The problem is the main relay is held on after the first time the ignition is turned on. The only way to release the relay is by removing it and replacing it in the system. Also the fuel relay doesnt even attempt to power the fuel pump. Im starting to think this ECU has "had it" Quote Link to comment Share on other sites More sharing options...
elbekko Posted April 25, 2011 Share Posted April 25, 2011 I had this problem on my CCV motor, worked through the EFI drawing and in the end found the following: On relay 87A you will see two pins with brown wires with an orange tracer, according to the drawing these should be connected together but on mine they weren't for some reason, connected them together with a shorting link and she fires up every time, take the link out and she won't fire at all, no idea why the pins weren't connected together though... HTH's Mick. Perhaps a leftover from an LPG installation? Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted April 25, 2011 Share Posted April 25, 2011 Is it Megasquirt-o-clock yet? Quote Link to comment Share on other sites More sharing options...
Hybrid_From_Hell Posted April 25, 2011 Share Posted April 25, 2011 ^^^^^^^^^^^^ :rofl: PMSL Nige Quote Link to comment Share on other sites More sharing options...
Hybrid_From_Hell Posted April 25, 2011 Share Posted April 25, 2011 Okay so a little update, I now have both relays fully functional and in the proper setup. The problem is the main relay is held on after the first time the ignition is turned on. The only way to release the relay is by removing it and replacing it in the system. Also the fuel relay doesnt even attempt to power the fuel pump. Im starting to think this ECU has "had it" Couple of things Did this unit / setup work on 1st install ? Can you confirm of the wires of the engine harness that you have connected, which wires are to where exactly ? Had this sort of nightmare of the Hybrid when I did a EFI Install, not all EFI Harnesses are exactly the same Nige Quote Link to comment Share on other sites More sharing options...
wee_arthur Posted April 25, 2011 Author Share Posted April 25, 2011 The unit has only just gonw in the car and this is the initial install that i am having trouble with. Okay so wires: (these are connected to the main cable connector as in diagram above.) White = Ignition, [checked this via the test in Nige's post further up] green/orange = main positive, [the diagram says brown but i reckon they ran out of brown wire; also tested ] white/purple = fuel pump then to ground black/yellow = not connected yellow = not connected orange/black = neutral switch [am i right in saying this is normally closed when out of park?] purple/yellow = not connected That is the 7 wires on the diagram that i have wired up, there is 8 wires on this plug however Don't know what the other is. Quote Link to comment Share on other sites More sharing options...
wee_arthur Posted April 25, 2011 Author Share Posted April 25, 2011 also on the coil front, am i right in saying there should be one white/black wire which comes from the MAF sensor loom tail and onto the negative side of the coil. And along with this there should be an ignition to the coil from another multiplug which includes all the other warning symbols etc. Hopefully get this resolved soon, another 4 hours this morning. Its like hitting your head off of the dash. Quote Link to comment Share on other sites More sharing options...
wee_arthur Posted May 1, 2011 Author Share Posted May 1, 2011 Hi again, A wee challenge for you. After another good few days on the defender i am not feeling any more confident about this conversion So the new ECU that Nige sent me had the same outcome so i now have a spare Chipped ecu maybe Anyway, gazing at wiring diagrams and using the technical checks that Nige showed me above. So here is where we start ... Start with the turning the ignition on. The following happens, The main relay clicks on fuel pump relay does nothing power is sent to the injectors and all sensors But when the ignition is turned off the fuel pump relay stays energized and the only way to deactivate it is to remove the relay and turn off the battery isolator. Another one of the diagnostic checks that does not turn up true is the mass air flow sensor which is supposed to show ranges of 0.4 to 0.6v with ignition on but i was getting 4v. Could this be the problem? would it start if the sensor was broke? and would this explain the fuel pump relay not going on? I apologise for the legnth of this but i wish to give a full picture. Thanks Again Quote Link to comment Share on other sites More sharing options...
Roverbo Posted May 3, 2011 Share Posted May 3, 2011 Could it be the connection around the "in-line resistor" (Item 15 on the schematic) ? This resistor gives the ECU information about that the ignition is in fact working, guess is it will turn the fuel relay off, if this impulse is missing (for safety reasons). If you haven´t got the resistor (black little plastic thing on my coil), it is specified to be 6,8 kOhms, ½ watt. Regards Bo Quote Link to comment Share on other sites More sharing options...
iomlt Posted May 3, 2011 Share Posted May 3, 2011 just disconnect the orange / black. just have the three connected Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted May 3, 2011 Share Posted May 3, 2011 The fuel pump relay won't do anything until the ECU sees pulses from the coil -ve and switches it on, you say it does nothing then you say it ends up stuck on, so it must get energized at some point Are you sure both relays are the right type now? It's been said before and always proved true - it's quicker to Megasquirt it than prat about trying to fix the Lucarse junk. Quote Link to comment Share on other sites More sharing options...
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