coldsubycz Posted August 14, 2012 Share Posted August 14, 2012 Oh. That's cheating. I know.... I'm very happy with the entire install except for that one part. I was very disappointed. Here is a picture of the fuel pump wiring all finished and wrapped in silcone tape. Link to comment Share on other sites More sharing options...
Aracheon Posted August 14, 2012 Share Posted August 14, 2012 Very clean! Looks good. Link to comment Share on other sites More sharing options...
coldsubycz Posted August 14, 2012 Share Posted August 14, 2012 Very clean! Looks good. Thanks! I'll get a bunch more pictures up of the rest of the install, just don't know when. It's 1 a.m. central time and should be in bed.... Link to comment Share on other sites More sharing options...
Aracheon Posted August 14, 2012 Share Posted August 14, 2012 Whenever is clever. I'm in the process of doing this myself, but my biggest hangups were the wires at the fuel pump. Your current pics already gave me a good idea of where things should go. Sent from my ADR6400L using Tapatalk Link to comment Share on other sites More sharing options...
coldsubycz Posted August 14, 2012 Share Posted August 14, 2012 Since I've already posted up random pictures, might as well keep going with that . Here is how and where I ran the Fuel Pump wires from the FPCM. I ran the wires through the grommet on the driver's side. I unwraped some of the existing black tape and then pushed the two 10awg wires through. It takes a little finess so be patient. I then ran the wire above the fuel tank to the FP. I used a fish cable and then pulled the cables through that way. Then I used some electrical tape and taped it back up. Looks just like factory! I also included a picture of my solder job on one of the FPCM pins. I had to file down some of the solder job in order for it to fit back in the harness. Link to comment Share on other sites More sharing options...
Aracheon Posted August 15, 2012 Share Posted August 15, 2012 I didn't think to use the existing channel on the grommet... I ended up punching a hole through next to it. (Dammit.) Your solder job on the harness pins looks near identical to mine. Speaking of those crimp pins... does anyone know where we can source more of them? Sent from my ADR6400L using Tapatalk Link to comment Share on other sites More sharing options...
Aracheon Posted August 22, 2012 Share Posted August 22, 2012 I've now got the Aeromotive kit wired in the same way as Cold does, and I've got an interesting dilemma. (I don't think it's the relay or the FPCM as the problem is the same with a different relay and with the STi and stock LGT FPCM.) I turn the ignition to on, fuel pressure jumps to the appropriate 3bar and I see 13.8 at the pump. Then once I see on my AP the fuel pump duty cycle drop from 100% to 0%, I'm still seeing 12.6v at the pump. Then once I turn the car on, I see the voltage jump into the mid 14v range until the FPDC drops to 33%, voltage jumps a little bit, then I see the fuel pressure drop to around 15-20psi and the AF correction slowly climbs to the max at 25%. There are no fuel leaks. Thoughts? Link to comment Share on other sites More sharing options...
Aracheon Posted August 23, 2012 Share Posted August 23, 2012 Addendum: So it's my understanding that the signal/power wire coming from the factory FP relay is supposed to be PWM, correct? If so: that wire (which is hooked to terminal 85 on the SPST relay) is getting 12.3vdc once the ignition is turned on. Upon seeing FPDC drop to 0, that wire is still receiving 12.3vdc. Link to comment Share on other sites More sharing options...
Scooby2.5 Posted August 23, 2012 Share Posted August 23, 2012 (edited) No the signal/voltage coming from the stock fuel pump relay is the voltage feed to the FPCM. With the rewire that signal/voltage from the stock fuel pump relay is now activating the coil in the new relay which then sends direct battery/alt voltage to the FPCM via the wire you run from the battery to the new relay. All this is doing is getting full voltage potential feeding the FPCM. The FPCM is then doing the modulating of the fuel pump voltage going to the pump. At key on the ECU requests 100% duty cycle so the FPCM sends max voltage to the pump. At the 33% or 66% duty cycle requests you should see less voltage at the pump. Edited February 1, 2013 by Scooby2.5 Link to comment Share on other sites More sharing options...
Scooby2.5 Posted August 23, 2012 Share Posted August 23, 2012 (edited) These readings are now with the new wiring/STI FPCM in place. 14.0v - At the battery 14.0v - At rear distibution block and new relay 13.5v - At the fuel pump (Tested during the first 10 seconds after startup)(Improved by 1v over stock wire) 100% Duty Cycle 07.7v - At fuel pump idle (improved 0.7v over my stock wire at idle)33% Duty Cycle This is the voltages Cold got after rewire, I added in what the DC you would be seeing next to his voltages feeding the pump from the FPCM At 66% duty cycle it should be in between the 7.7v and the 13.5v Edited August 23, 2012 by Scooby2.5 Link to comment Share on other sites More sharing options...
Aracheon Posted August 23, 2012 Share Posted August 23, 2012 Those voltages are exactly what I was expecting to see... but for some reason are not. So if the FPCM is doing the modulation, and neither the STi or the LGT module are behaving as expected (when they WERE working prior to the rewire, just with not enough voltage), I have to entertain the possibility that I somehow now have two bad modules, or I screwed up a very simple wiring job. I'm going to go out on a limb and assume it's the latter - any thoughts on what conditions would cause the symptoms I'm seeing? How come the module is not stepping down the voltage during the 33% and 66% duty cycles? Sent from my ADR6400L using Tapatalk Link to comment Share on other sites More sharing options...
Aracheon Posted August 23, 2012 Share Posted August 23, 2012 I went and double-checked that the polarity from the FPCM to the FP was not reversed, and in fact I have it correct. (FWIW - the DW65c primes but does not build fuel pressure if it is wired backwards.) Went out and re-tested the system just to make sure I had the right numbers: At key on, I'm seeing 12.6vdc at the pump during the priming phase (100% FPDC), and the same voltage once it finishes priming (0% FPDC.) Car running, FPDC at 100%, fuel pressure at 3 bar, I'm seeing 13.8vdc at the pump. Car running, FPDC at 33%, fuel pressure drops to 1 bar, I see 14.2vdc at the pump. With FPDC at 100%, the behavior is what I would expect. But I don't understand why the voltage increases and the fuel pressure drops off when the FPCM steps down the duty cycle to 33%. Link to comment Share on other sites More sharing options...
Scooby2.5 Posted August 23, 2012 Share Posted August 23, 2012 (edited) What voltage to you have at the battery with car running? What voltage do you have at the input of the new relay, at the end of the wire you ran from the battery? What voltage do you have coming from the stock fuel pump relay...this should be the wire that should now be connected to the spade on the relay you added actuating the coil on theat new relay? We dont need fuel pressure at this point, we dont need 0% numbers. Just measure the output of the FPCM at key on (first few seconds is 100% duty cycle) and also at idle (33% duty cycle)? Edited August 23, 2012 by Scooby2.5 Link to comment Share on other sites More sharing options...
Aracheon Posted August 23, 2012 Share Posted August 23, 2012 (edited) Voltage at battery, engine running: 13.8v Voltage at new relay input, engine running: 13.8v Voltage from stock fuel pump relay, engine running: 12.3v Output of FPCM at key on (100%): 12.6v Output of FPCM at idle (33%): 14.2v Edited August 23, 2012 by Aracheon Link to comment Share on other sites More sharing options...
mwiener2 Posted August 23, 2012 Share Posted August 23, 2012 Depending on the type of meter you are using, it could read the average voltage of the PWM signal or the actual full voltage pulse. So one meter can read 13v while the other reads 7.2 You need a scope to properly see a PWM signal. My Mods List (Updated 8/22/17) 2005 Outback FMT Running on Electrons Link to comment Share on other sites More sharing options...
Aracheon Posted August 23, 2012 Share Posted August 23, 2012 Depending on the type of meter you are using, it could read the average voltage of the PWM signal or the actual full voltage pulse. So one meter can read 13v while the other reads 7.2 You need a scope to properly see a PWM signal. Mike, I considered that. But let me throw something else into the fray: prior to adding the new relay and the STi FPCM, I was seeing the expected voltage behavior at the fuel pump with both of my multimeters. (Granted, the numbers were LOW, but the control module was behaving as expected.) Now it's not. Both my STi and LGT FPCM are exhibiting this weird-ass behavior after the new relay went in. Is it possible I somehow fried both FPCMs in this ordeal...? Link to comment Share on other sites More sharing options...
Aracheon Posted August 23, 2012 Share Posted August 23, 2012 The vacation pics make mention of the voltage values we should also be seeing from the ECU to the FPCM. http://i.imgur.com/9FrkQ.png I tested both of these wires, and while I was seeing between 11-12v on the Light Green w/Red wire, I was seeing 1.4v and 3.96v on the Light Green wire. (Not sure if that even matters or not.) Link to comment Share on other sites More sharing options...
Scooby2.5 Posted August 24, 2012 Share Posted August 24, 2012 (edited) Bad ground maybe??? I dont know without looking at it. Sounds pretty weird You sure you have everything wired according to the diagram? Edited February 1, 2013 by Scooby2.5 Link to comment Share on other sites More sharing options...
Aracheon Posted August 24, 2012 Share Posted August 24, 2012 So just for gits and shiggles I ran the output of the new relay directly to the fuel pump as illustrated in Aeromotive's instructions. A direct 13.8v at the pump and all of my hesitation and high AFR issues are gone. Fuel pressure rises with boost as expected - so for diagnostic purposes, I'm going to assume the rest of my fuel system is OK. Back to the control module: it's weird as shit - the only thing I can think of at this point is that I've angered lady luck and both of my modules are somehow bad. I considered the ground as a possible culprit, so I've tried two different grounding points, and even wired the ground to an 8AWG cable that I routed up to the negative terminal on the battery. Same results. And yes - I've poured over every wiring diagram I could get my hands on, and quadruple-checked my wiring against Coldsuby's pics. It's all spot on. Link to comment Share on other sites More sharing options...
integroid Posted August 24, 2012 Share Posted August 24, 2012 I would check the factory ground for the FPCM.....Actually, I would just use a different ground and bypass the factory ground. Link to comment Share on other sites More sharing options...
Aracheon Posted August 24, 2012 Share Posted August 24, 2012 I would check the factory ground for the FPCM.....Actually, I would just use a different ground and bypass the factory ground. Mine's set up the same way Coldsuby's is - soldered a 10awg wire to the pin on the FPCM. I've routed it to a pretty substantial factory grounding point at the rear of the wagon on the left side, as well as to the bolt that secures the FPCM to the sheet metal, as well as directly to the battery via an 8awg cable. Same results. (Where is your FPCM grounded at, Integroid?) The new relay is routed to the factory ground wire for the FPCM, though. I suppose I could run a new wire for that, although the relay seems to be working properly. Link to comment Share on other sites More sharing options...
coldsubycz Posted August 25, 2012 Share Posted August 25, 2012 (edited) ^I'm no expert, but could the "new" relay from Aeromotive be bad (I think I read that you got the Aeromotive kit?)?? I used the Hella relay that integroid suggested. That's the only thing I can think of. PS, I would buy a quality relay and not a cheap $1 relay. I have seen the cheap relays melt and fail after time. The one below is not too expensive and is a high quality relay. Amazon.com: HELLA 003510087 30 Amp 12V Mini SPST Relay with Bracket: Automotive Edited August 25, 2012 by coldsubycz Link to comment Share on other sites More sharing options...
integroid Posted August 25, 2012 Share Posted August 25, 2012 My relay is grounded at the same point the FPCM is. It very well could be the relay. I would change the grounding point and maybe even purchase a higher quality relay. Link to comment Share on other sites More sharing options...
Scooby2.5 Posted August 25, 2012 Share Posted August 25, 2012 ^This Link to comment Share on other sites More sharing options...
Aracheon Posted August 25, 2012 Share Posted August 25, 2012 I actually have the Hella relay also. Let me try grounding both to the same spot and swapping the relay to see what happens. Sent from my ADR6400L using Tapatalk Link to comment Share on other sites More sharing options...
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