WHY DONT MY RELAYS WORK???????

[ShouldaHadaV8]

ok its been a while since i first started bringing my 92 240sx back to life, i swapped a 96 ka and replaced it with all new parts and sensors but nothing really changed, for some reason im having trouble with my realys, they wont work even if i put a new relay in, but it will work when i jump it with speaker wire which is what ive been having to do, one of the only things i haven't replaced is the lower transmission harness, and i was told it could be the ecu but it seems to be working fine. any help will be appreciated the car has a slight hesitation but there are so many things which can cause it, i want to figure out this relay problem so that i can rule that factor out.

[ShouldaHadaV8]

[ShouldaHadaV8]

im still going to replace the OEM lower harness for the transmission and all transmission senors, then get a walboro 255, ground it better. eventually it will work CORRECTLY

[ShouldaHadaV8]

I bought the lower harness we will see if it fixes the problem, if not then im thinking about buying the xcessive manifold and a walboro fuel pump. im not sure that will fix the relay problems but i think it will fix the problems with the hesitation, i still dont know what would cause the relays to not work the way they do.
I sold my VW just to fix this car , almost bought a 93 300zx for $1500 but decided just to fix this p.o.s .I hope I made the right decision

[ShouldaHadaV8]

tommorrow the harness should be here, along with new NGK plug wires, and heater core hoses.

im also going to test the ecu and see what it says. if it doesn't run right after these parts im going to buy the xcessive manifold, a walboro 255, every other sensor i haven't replaced, i believe the only things i haven't replaced are the transmission sensors , the knock sensor, and the iacv( which im not going to buy,i would rather go xcessive). Does anybody know about how often the pcv valves go out on ka24de's ? im not sure how it would run if it was bad?

theses car are a bi_ch to get to run right

[ShouldaHadaV8]

I replaced the OEM lower harness. it didn't fix the problem.... im kind of at a stand still im not sure what else may cause the relays not to work.
If you look at the pictures you can see both the speaker wire jumping the circuit ,and the wires leading to the relay. This has been coming up on almost a year since I swapped the motor , I cant believe I still have not even drove it.

Im still gonna try to test the ecu. Who knows maybe I need to replace it?

[ShouldaHadaV8]

I tested the ECU and it came back code 55
I thought maybe it was a ground problem, but it didn't seem to change anything atleast not my major problem which is that it boggs when you accelerate , it seems like i either have old gas in the tank which could be bad or I have some type of Air/Fuel mix problem.
Im so pissed.I just want it to run right ,but i dont know what to fix

[vancouverbc]

do you know how a relay works? u might get a multimeter and test to see what is wrong.

[ShouldaHadaV8]

I have a multimeter. but ???? i've tested things like maybe bad grounds and resistance, and replaced the lower harness, and tried to buy new relays. but I just jump the relay with speaker wire. and the it will run, its the only thing i can get to work. and for some reason the last three people who have owned this car couldn't get the battery to stop draining( the alternator works fine), i cant figure it out either i just take the terminals off every time i shut it off.
But the first the time i checked out my ECU it read 55, And I was confused because I thought the car idles fine even regardless of jumping the relay ,but my major problem with the car was that it would bog when i tried to accelerate. I wanted to test the ecu again just to make sure so i let the car idle for about three minutes then reved it up slowly and then shut it off and tested the codes again and it read 34. so i know i have to replace the knock sensor ( THANKS for the tutorial on how to take it off without removing the manifold ) its one of the only sensors I didn't replace.
I dont think thats gonna fix the relay ,But it may be drivable.
but as far as the relay not working it never happened until i replaced the motor so ???? but its the third motor that's been in it i believe.
I agree with you though i need to get a consult cable.

[vancouverbc]

your knock sensor is probably fine. just triggered by boggin. ecu can be fried and still give code 55. you need to know how to test the relay operation. if it is fuel pump relay, you need to see if it gets constant positive and if the ecu sends a negative pulse when car first starts. you wont solve the problem by replacing parts.

http://www.the12volt.com/relays/relays.asp

[ShouldaHadaV8]

i went outside and tested the relay. it get constant power ( 12v) on both right side terminals with out the key in the ignition, when the battery was connected. i have to look the ecu wire layout to see about the negative pulse.
Are you trying to tell me the ECU may be fried? I wont order a knock sensor if I dont need one.
What do you recomend testing or doing.......or buying.

[ShouldaHadaV8]

wiring is not my specialty

[ShouldaHadaV8]

your knock sensor is probably fine. just triggered by boggin. ecu can be fried and still give code 55. you need to know how to test the relay operation. if it is fuel pump relay, you need to see if it gets constant positive and if the ecu sends a negative pulse when car first starts. you wont solve the problem by replacing parts.

http://www.the12volt.com/relays/relays.asp

well we tested the car with a consult cable running nissan tech. it reads that everything is right but once you hit the gas the ignition timing drops. its idleing at a perfect 750. we tried swapping out the maf sensor but it had no effect. ( im not sure if im am approaching the problem correctly)
if you have any advice....i need it.

[NISMO24096]

Hey man, next time I go to my parents I'm gonna bring another ECU for you to through in that thing and see if we cant rule out something else...talk to ya later...Lee

[ShouldaHadaV8]

your the man lee....i will be there.

[AHall]

Did you ever resolve this problem????

This seems to be somewhat common, but no one has posted a solution that I can find.

[ShouldaHadaV8]

actually yes i did, it my #28 ecu ( it worked fine before the motor swap ).... im actually borrowing a #29 from NISMO24096 its from an auto, which fixed the problem.

[AHall]

Thanks for the response. I think my #28 ecu needs to be replaced as well.