paddles

Hey Guys, I'm currently finishing off an rb25det into 260z conversion and there's a few bits on the motor that I'm unsure of. Would love to know what these bits do and if they are necessary (if they aren't necessary it would be nice to tidy things up a bit!). Any help would be great! 1) Has coolant lines running into and out of it - located on a sammich plate between block and oil filter. 2) Located on the underside of the inlet manifold, this guy has coolant lines running into and out of it. Also has two wires going into it. 3) These two connectors are connected to... nothing... To the left of the pic the wires have been cut. What did the wires go to and are they necessary? Had a look at a wiring digram to try and sort this one out but it didn't seem to cover everything. Any help would be very much appreciated! Cheers

Ok sweet, thanks again! Looking to keep the motor standard for now, maybe a wee bit of extra boost later. Running a low pressure lift pump into surge tank from which the high pressure pump feeds; as the 260z tank can't be good in terms of fuel surge.

Forgot to thank you for that pinout diagram kiwirs4t, cheers! Does the diagram accurately represent the location/shape of the plug to the ecu? I notice with the pin diagram I've been working off (link below) the plug shape and number of outlets is an exact match to the plug/ecu in the car. The alternative diagram seems to have a much different plug shape - is this a valid way of telling the two apart? Either way I believe the wiring issue is sorted now as the relay is turning on for 4 seconds when ignition is switched ON and for that period of time I'm getting a 12v supply to the pump! I guess now all I can do is replace both pumps and see how we go. Pinout diagram: http://wiki.r31skylineclub.com/images/thum...ECU_Pinouts.jpg

Thanks for the help guys, issue #1 solved! Sorry blind_elk I misread your original post - I thought you meant take pin 1 of ecu to ground (not pin 1 of relay) Doh! For reference, the relay was clicking when ignition was switched on - but no power was getting through the switch side. So I did as blind_elk suggested and took pin 1 of relay to ground and I was getting 12v to pump! So this suggests the ecu may not have been switching the relay yeah? Anyway I removed the additional earth wire and inverted the current direction through the coil side of the relay, nothing... So connected it back up the way it was originally and tadah it works! So overall teh wiring is exactly how it was in the beginning - leading me to believe that perhaps the relay was dicky and wiring it up backwards (or perhaps due to additional earth) released the switch... Or something... The relay will now turn on for about 4 seconds every time ignition is switched on. This is the ecu turning on the pump to prime, correct? Anyway, I'm a tad confused, and have decided that a dicky relay was the culprit... Unless anyone has a better (read: more educated) synopsis? Although now we've found that both the low and high pressure pumps are rooted.. Huzzah... Any suggestions as to a good replacement high pressure pump? Currently running an external unit - I believe it is a VL unit. Thanks again for the help guys!!

The car will run if pumps are hotwired so ECU is 'alive' then yeah? (sorry not too sure what you mean by 'alive'; do you mean it is receiving power?) What is Pin 1? I don't have the ECU pinout diagram on me at the moment... What should/shouldnt happen when I ground it? I thought power could go through either way? Although thinking about it I suppose if current went through the coil the wrong way round it may push/pull the switch the wrong direction due to an inverted magnetic field...? You may be on to something... I'll give it a crack anyway Thanks muchly for the help guys!

Thanks for your input! Here's a Van Gogh-spec diagram of how the relay is currently wired if its any help. Although this wiring was completed before we got the car so it's a case of trying to work out what has and hasn't been done as we go! with ignition on Im getting +12v at pins 1, 2 and 3 but not at 5. So this leads me to believe the wiring isn't faulty and either the relay is faulty or perhaps the ECU isnt switching the relay for some reason. Any ideas why the ECU might not switch the relay? Is there maybe some signal it must receive from another source (say an ignition feed?) before it will switch the pump on? Ie. one of the ecu feeds has not been connected or something? Although that may be farfetched as it runs fine with pumps hardwired...

Also when should hte ecu trigger the fuel pump? I assume the pump should be active when ignition is switched on to build pressure prior to cranking the motor?

Hi guys, Apologies if this is in the wrong section - couldn't see a section for electrical questions... Anyway, we have recently purchased a 260z with rb25det (standard ecu) as an unfinished project. The only real running problem remaining is that the fuel pumps are not getting power - with a battery pack applying 12v to pumps the car will run no problems. Now I'm attempting to work out why the pumps arent getting power. For reference, I'm working with the wiring diagram found here: http://www.meggala.com/rb25detenglish.html Based on this diagram, I believe that the fuel pump relay is triggered by the ecu switching to ground at pin 18 of ecu. Since constant +ve is supplied to pin 1 of fuel relay (check out bottom left of diagram) I figure this is the only way the relay can be triggered. Is this correct or am I way off the mark? With battery connected, ignition on, I'm getting +12v at pin 1, 2 and 3 (not 5). At one stage I removed the fuel pump relay from its socket (creating an open circuit) and I still had +12v at both pin 1 AND pin 2 of the relay. I can see why 1 would have +12v but why oh why would pin 2 of relay have 12v? The only conclusion I can draw is that perhaps I have misunderstood the diagram and the ecu supplies the 12v for switching the FP relay. Any help/suggestions would be greatly appreciated! Please let me know if more info is required. Cheers, Paddles