Jdm swap issues
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Jdm swap issues
Hey guys. I hope that someone else out there have had the same issues that I am having not. My engine is an S% jdm, no emmissions, rb dp and exhaust. Here is whats up. My car runs fine on the jdm ecu under no load. At load, if i press the gas more than half way, it bogs down. I am useing the n/a harness. Maybe I hooked up the injectors wrong? If I use the n/a ecu, it instafloods. The same with a the border jdm ecu that I have. I can only get it to start with the jdm stock ecu. I have fire to all plugs.
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What is a S% JDM?
If it's a series five, maybe it's OMP limp mode. Just a wild guess.
Or, are you using a Turbo Boost sensor or non turbo Boost sensor? Need Turbo sensor.
Turbo or non turbo AFM? Turbo prefered.
What's the number on the ECU? N374? Or??????????
Just driving along at little throttle, can you go over 70 mph. I said little or light throttle to get to over 70.
What year car?????
You did use the non turbo EM harness on the engine. Right? Should have.
\
If it's a series five, maybe it's OMP limp mode. Just a wild guess.
Or, are you using a Turbo Boost sensor or non turbo Boost sensor? Need Turbo sensor.
Turbo or non turbo AFM? Turbo prefered.
What's the number on the ECU? N374? Or??????????
Just driving along at little throttle, can you go over 70 mph. I said little or light throttle to get to over 70.
What year car?????
You did use the non turbo EM harness on the engine. Right? Should have.
\
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I guess I hould have been a little more specific. Yeah, its an S5. N374 ecu<----the one that it starts up with. The border racing is also an N374. I also tried with the 351 but it flloded instantly like with the programmed ecu. Turbo AFM and boost sensor with fbcd. OEM n/a harness being used. I have not tried to go past 3rd gear with the car, but i guess it would do 70 at light throttle. It revs fine under no load at like 1/4 throttle but if you floor it, it falls on its ***. Its an 89 gxl. I would guess it was in limp mode too if it didnt flood instantly with all the ecus that are supposed to work. A vaccum leak is possible also since I blocked everything off, but again with the flooding issue.
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If it were doing the same thing with all 3 ecus then I would say maybe....Its worth a shot anyway. Im going to to unhook it this afternoon or install the n/a one and see what happens. I have also thought maybe its the fuel filter but wtf would it be the filter if it floods with the ecus that are supposed to work....
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Well, i checked the afm, and alot of other stuff and didnt find anything so i took apart the intake and rechecked my wires to the fuel injectors...looks like I was in the same boat as you, somebody. Thanks for all the help guys
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Are those stock secondary injectors? I was thinking maybe they're too large. Like 720's or something like that.
I don't know what's wrong. You might try taking that fuel cut defender off and go for a ride with it out of the system.
The boost sensors vacuum line.........is it getting vacuum/pressure off the engine. Like take its vacuum hose off while at idle and feel the line to see if it's getting vacuum.
If you had a meter, I'd suggest back probing the green/yellow wire on the boost sensors plug (with it connected up to the sensor) and see what the voltage is. You'd do that at idle and compare it to the FSM figure
You'd just unbolt the sensor from its bracket and turn it over, but leave the elect plug on it and the vacuum hose on it. And at idle you'd backprobe the green/yellow wire.
When you floor it and it falls on it ***, are the rpms over 3800rpm? Or does it fall on its butt at lower rpms?
I don't know what's wrong. You might try taking that fuel cut defender off and go for a ride with it out of the system.
The boost sensors vacuum line.........is it getting vacuum/pressure off the engine. Like take its vacuum hose off while at idle and feel the line to see if it's getting vacuum.
If you had a meter, I'd suggest back probing the green/yellow wire on the boost sensors plug (with it connected up to the sensor) and see what the voltage is. You'd do that at idle and compare it to the FSM figure
You'd just unbolt the sensor from its bracket and turn it over, but leave the elect plug on it and the vacuum hose on it. And at idle you'd backprobe the green/yellow wire.
When you floor it and it falls on it ***, are the rpms over 3800rpm? Or does it fall on its butt at lower rpms?
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Hailers, I would take advice from you about wireing before anyone else on here. Thanks alot for your time. I have looked over alot of your posts and you have said time and time again to label your connections. I know its kind of common sense but I I got in a hurry and didnt. The problem was the same as Somebody had. A couple injectors were hooked in backwards. I feared that that was it from the start, but I was looking for a more simple way out. But, I took apart the top end and fixed my problem.
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