huelsdonk Posted September 6, 2010 Share Posted September 6, 2010 so i got 1987 gl wagon 5sd d/r mpfi for free. the engine was blown and many other redneck fixes have been done to say the least.. i soucrced a 1985 gl wagon fwd auto carbed for the swap and parts to bring the 87 to daily driver status. so i swapped the engines, engine wiring harness, eveything i need to, but now i cant get my fuel pump working. i swapped in the new pump but cant figure out what i gotta do to get it to work. i can do the good old fashioned cut and splice but id like this to work all day everyday so i have a driver. i even jumpered the park and nuetral safety switch so it turns over and has spark just no fuel pump. please help!! it must have something to do with swapping the harnesses i think Quote Link to comment Share on other sites More sharing options...
2manetoys Posted September 6, 2010 Share Posted September 6, 2010 So which vehicle is getting which parts? did you put the motor from the 85 into the 87? did you switch the MPFI into the 85? Answering these questions will help diagnose the problems. Quote Link to comment Share on other sites More sharing options...
huelsdonk Posted September 6, 2010 Author Share Posted September 6, 2010 (edited) the 87 is getting the parts. the harness was torn apart from the mpfi and the engine was blown from overheating, so i swapped in the harness, fuel pump, engine and all related parts from the 85 to the 87. so im keeping the carb setup from the 85 Edited September 6, 2010 by huelsdonk Quote Link to comment Share on other sites More sharing options...
GeneralDisorder Posted September 6, 2010 Share Posted September 6, 2010 You have to use a carbed fuel pump and you need the fuel pump control unit and associated wireing, etc for the carbed pump to be properly wired in. In the SPFI car (trust me it's not MPFI), the fuel pump is controlled by the ECU which closes a relay and starts the pump durring cranking or running - since you tore out the SPFI harness you also removed the ECU's tach signal and in any case the ECU isn't going to play nice with a carb. You have to rewire the pump to run off the carbed FPCU instead. GD Quote Link to comment Share on other sites More sharing options...
huelsdonk Posted September 6, 2010 Author Share Posted September 6, 2010 (edited) yeah i pretty much know all that and did all that, i just wanted to know if anyone could help me as to what wires im looking for. or relays or what im looking for or where. i'll put in my own relay if i have to i just need to know where to find the wiring under the dash, or in the engine compartment or wherever, i guess. so i guess i just didnt ask the right question :-\ and maybe theres been even more swapping done before me cause it did have mpfi for sure. Edited September 6, 2010 by huelsdonk Quote Link to comment Share on other sites More sharing options...
GeneralDisorder Posted September 6, 2010 Share Posted September 6, 2010 MPFI is a 4 injector system. An '87 D/R (unless it's a turbo of some kind) would either be carbed or would have the single injector system (SPFI). If you swapped the dash harness and engine bay harnesses then the FPCU is located right above the hood release latch on the driver's side kick panel. It needs switched power, ground, tach signal, and it has a hot lead for the fuel pump as well as another one for the choke. GD Quote Link to comment Share on other sites More sharing options...
huelsdonk Posted September 7, 2010 Author Share Posted September 7, 2010 its alive!!! i got it running. thanks for all the help. now what wires am i looking for to do my tach signal and choke and everything? Quote Link to comment Share on other sites More sharing options...
GeneralDisorder Posted September 7, 2010 Share Posted September 7, 2010 I'm not even sure *what* you have done - if you swapped the harnesses wholesale then you should have those already taken care of - so I guess my question is why isn't that stuff working? You say you swapped all the wiring over - so what didn't you swap? Or what did you swap? Hell - I can't follow your plot man. GD Quote Link to comment Share on other sites More sharing options...
Gloyale Posted September 7, 2010 Share Posted September 7, 2010 Swapped an SPFI wagon to Hitachi carb??? Man, what a downgrade. I'll bet the problems it had from before would have been easier to fix. At least would have been easier for us to help troubleshoot. You've swapped so much it's gonna be hard for us to know what oyu have going on. Add to that the fact that acurate wiring diagrahms for 85 and 87 are both hard to find....and both sort of oddball as compared to the 88+ stuff. Glad it's running......truth is, since you swapped it all, you will be the one with the best bet of diagnosing problems. Quote Link to comment Share on other sites More sharing options...
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