Uberoo Posted March 12, 2007 Share Posted March 12, 2007 My car was originally a carbie motor.Im 99.8% done with the EJ swap.The only things left are install FI fuel pump and assorted FI lines.The fuel pump is out of an 89 MPFI car.physically it bolts right in.the connector though is different. Both connectors in question have two wires going in to each other. are the wire positions the same in each connector?ie carbie connector [ + - ] mpfi connector [ + - ]? also is it required to connect the signal wire from the ej harness to the fuel pump?The pump as it is wired with the EA harness starts pumping when I turn the key. Quote Link to comment Share on other sites More sharing options...
Phizinza Posted March 12, 2007 Share Posted March 12, 2007 also is it required to connect the signal wire from the ej harness to the fuel pump?The pump as it is wired with the EA harness starts pumping when I turn the key. I think the reason you power the pump from the EJ harness is because it only gives it power when the motor is turning over. Now the reegulator on the EJ engine opens when you have vacuum, so if your pump is on and the motor isn't turning over the pump is building up pressure and may pops some pipes or even die. I powered my pump off the EJ's pump relay. But on my first start it was just wired to the battery. So the engine will run even is the EJ harness has nothing to do with the pump. Quote Link to comment Share on other sites More sharing options...
Uberoo Posted March 12, 2007 Author Share Posted March 12, 2007 ok then I will tear apart the interior and run the wire in as far as it will go(getting tired of solding with my 25W pen) Quote Link to comment Share on other sites More sharing options...
psylosyfer Posted March 26, 2007 Share Posted March 26, 2007 I think the reason you power the pump from the EJ harness is because it only gives it power when the motor is turning over. Now the reegulator on the EJ engine opens when you have vacuum, so if your pump is on and the motor isn't turning over the pump is building up pressure and may pops some pipes or even die. I powered my pump off the EJ's pump relay. But on my first start it was just wired to the battery. So the engine will run even is the EJ harness has nothing to do with the pump. Should I be concerned? after reading this thread I'm wondering if I should be concerned about my fuel pump (they are spendy as I'm sure you know) My pump cycles on/off as soon as the key is on, Before start! I thought this was normal. isn't there a pressure regulator with a relief to send excess fuel back to the tank? Thus preventing overpressure damage. The car had a bad fuel pump when I bought it. Now I wonder if it failed because I have a problem with the associated circuitry, I hope I misunderstood the thread! Is My system NOT supposed to cycle before the engine is running? I'm sure the entire circuit is stock, But may have a problem if pump should not run with engine off. 91 loyale. Quote Link to comment Share on other sites More sharing options...
Uberoo Posted March 26, 2007 Author Share Posted March 26, 2007 I have a ford fuel pump wired to a switch...But on yours when is the pump on? Quote Link to comment Share on other sites More sharing options...
psylosyfer Posted March 26, 2007 Share Posted March 26, 2007 as soon as the key is turned on it starts cyclic on and off for about 5 second intervals, I think it does this till you turn off the key. Quote Link to comment Share on other sites More sharing options...
nick@vlmspec Posted August 20, 2007 Share Posted August 20, 2007 as soon as the key is turned on it starts cyclic on and off for about 5 second intervals, I think it does this till you turn off the key. was this ever figured out...mine does this also, and is from what it appears to be an all stock 89 loyale Quote Link to comment Share on other sites More sharing options...
psylosyfer Posted August 20, 2007 Share Posted August 20, 2007 I "think" this is correct, my 91 always does this and runs great. Quote Link to comment Share on other sites More sharing options...
azsubaru Posted August 20, 2007 Share Posted August 20, 2007 Atleast on the SPFI EA82's the fuel pump should cycle for a second or so when you turn the key on. That's how I diagnosed mine when it went bad - silence from the rear when I turned the key on! Quote Link to comment Share on other sites More sharing options...
mrdeep2001 Posted September 12, 2007 Share Posted September 12, 2007 Atleast on the SPFI EA82's the fuel pump should cycle for a second or so when you turn the key on. That's how I diagnosed mine when it went bad - silence from the rear when I turned the key on! What problems were you having with your car when you found it was the fuel pump? Any running issues, or just silence from the rear? Quote Link to comment Share on other sites More sharing options...
psylosyfer Posted September 12, 2007 Share Posted September 12, 2007 What problems were you having with your car when you found it was the fuel pump? Any running issues, or just silence from the rear? Before replacing my fuel pump, The car wouldn't start. The previous owner said it was running but losing power on hills. Quote Link to comment Share on other sites More sharing options...
daeron Posted September 13, 2007 Share Posted September 13, 2007 Atleast on the SPFI EA82's the fuel pump should cycle for a second or so when you turn the key on. That's how I diagnosed mine when it went bad - silence from the rear when I turned the key on! not all of us-- some ECU's (mine included) only turn the fuel pump on when the key is in start or the engine is running. Quote Link to comment Share on other sites More sharing options...
azsubaru Posted September 17, 2007 Share Posted September 17, 2007 What problems were you having with your car when you found it was the fuel pump? Any running issues, or just silence from the rear? My car sometimes simply wouldn't start. After I noticed there was no noise when I turned the switch on, I would go back and whop on the fuel pump a couple times with a BFH and the pump would cycle the next time I turned the key, then run fine for awhile, no loss of power or any other symptoms. After a couple weeks of this, it started dying while I was driving down the road, just ran out of gas and quit. A few more whacks with the hammer (not fun at 5PM on I-10 in Phoenix!) and it would run maybe 30 minutes and die again, so I decided to replace it before it died altogether. I replaced it with an F150 fuel pump from NAPA, a bit of a pain to get in and a little noisy, but it works fine. Quote Link to comment Share on other sites More sharing options...
azsubaru Posted September 17, 2007 Share Posted September 17, 2007 not all of us-- some ECU's (mine included) only turn the fuel pump on when the key is in start or the engine is running. Yeah, I guess most of my replies have a disclaimer of "at least on my 91" because of the variations. One question - I don't understand how yours knows whether the engine is running or not - do you know how that part works? Quote Link to comment Share on other sites More sharing options...
daeron Posted September 17, 2007 Share Posted September 17, 2007 Yeah, I guess most of my replies have a disclaimer of "at least on my 91" because of the variations. One question - I don't understand how yours knows whether the engine is running or not - do you know how that part works? I have been meaning to look into that; I know most vehicles with a flapper-type AFM incorporate a switch there that energizes the fuel pump relay (which is also energized by the key going into the "start" position) but since mine is a hotwire MAF type (as is all SPFI) it is almost definitely switched inside the ECU. My guess is that the ECU is signaled by the CAS? In any case, I am not entirely certain, nor does it matter (as long as I continue having no fuel pump issues, heh.) Quote Link to comment Share on other sites More sharing options...
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