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Discussion Starter #1 (Edited)
after about 2 weeks of swap progress the car is finally complete. car started but with hardwired fuel system.

Ill make this comlpicated problem short. Basically my relay will not give signal to the fuel pump or anything in is range. The relay controls the fuel pump ecu, gauges, and idle controller. We were able to start my car but only with the fuel pump. No gauges to see temp or speed and no idle control so rought idle.


I spliced the 3 wires from the na side fuse box to the 4 from the 6 spd tt harness i have.

For some reason when i turn the key in "on" position nothing gets signal. It seems the ecu will not tell them to turn on. What is going on? have any of you had this problem.

I bought a tt fuel pump ecu if that might help. basically when we hardwire the pump we give it straight 12 v and right when my friend taps that wire i start car. its kind of like a fuel pump switch on a drag car. its not worth it thought because everything else the relay controls doesnt work either.

I followed this link but it didnt help.

here



cliff notes for anyone who doesnt want to read this all:

car gets no fuel pressure when key is in "on" position. Hardwired fuel pump to test if it runs and it runs fine. relay will not give signal to anything in its path: fuel pump ecu, gauges (expect tach obviously), idle controller.
thanks for the help
 

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T88 YOU
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check voltage coming out of ecu, if you got voltage coming out of ecu but no continuity in the relay, the relay is bad, if there is no voltage coming out of the ecu you got bigger problems.
 

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feeding your habit
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Why did you hardwire the pump instead of using the stock wiring? You're stock twins... you have no need for anything more than the original NA pump since your JDM motor has 440's (or did you swap them?) and the NA pump will probably supply enough fuel to make the JDM 280HP. If you swapped cams, turbos and injectors to USDM, you should go walbro or TT pump.... but remain on stock wiring.

either way to fix the problem, put all the wiring back to stock except for the one wire you spliced at the front fuse box. The HP you are making doesn't warrant hardwired fuel and you'll be more than fine with a stock TT or Walbro 225LPH HP pump.

I just did mine, all my wiring is 100% stock on my NA chassis. I installed a USDM 6 speed ENGINE harness, spliced the fuse box wire, turned the key and haven't looked back.

I'm running a walbro pump on stock wiring.

Get rid of the relay.... you don't need it. Lose that 6 speed tensioner bracket you cobbed up too, before it tangles up your belt, fucks up your accessories and dings the hood from the inside!

:)
-M
 

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98mkiv quotes

"Get rid of the relay.... you don't need it. Lose that 6 speed tensioner bracket you cobbed up too, before it tangles up your belt, fucks up your accessories and dings the hood from the inside!"

Ha Ha. I can just picture this happening.

I second 98mkiv's Suggestions and also speak from experience in my NA to TT swap. Put all wiring back to stock and you have correctly done the fuse box mod,so that is fine.

Also:
Check your connection at the ecu. It has to be tight, but don't overtighten and strip out the bolt.
 

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I had the same problem....check the orange connector off of the engine main harness..
what happens you push it and it seems like its in, but their is a white hook on top of that connector...pull it forward,,it will allow the connector to go more in..
had the same exact problem with my swap...
as for fuel you can PM me..
i have completed this swap and I am running..
any other questions PM me..


Rick
 

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Discussion Starter #8
my friend and i went to sp and he made a new relay in the trunk. the same design that would be used on the sp fuel system but on the stock fuel system. it works but once i turn the key in on position fuel stays flowing non stop which is annoying. car ran great though.


i did have the orange connectoer loose. do you think i should cut all wiring and put back to stock and see if it works just based on the fact i clicked the orange clip in the right way.



also can i strip out the ecu harness bolt. i thought it just keeps spinning at the end and that means its done.
 

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feeding your habit
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Step 1: lose the tensioner bracket and shock, get a junk AC compressor and correct belt.

Step 2: return all wiring to stock except the FB mod. Start car and enjoy a little reliability.

You have a long road with tuning, etc in front of you, why make it more painful with these mods? You still haven't said why you ran the relay in the first place. Running it the way you are will shorten pump life and make the car annoying if it's not running but the key is on.

If there is a problem, find the problem and fix it. Don't leave it and create a new problem with some workaround.

-M
 

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Discussion Starter #10 (Edited)
well heres what i did. another forum member said to check the orange clip in the ecu because it might not be fully clamped. that was true. i tightened the clip completely and pulled off all the relay stuff we did and only left the fuse box mod.


The car started as it should of the 1st time.

but now it idles like shit again as it did randomly. the car ran perfect for couple hours and once we tried hooking up tach it went bad. raised idle and car ran good. 30 min later once i tried another start it ran like shit again.


my tt fuel pump ecu should be here today. will that help maybe?

also what do you mean by a lot of tuning ahead of me?



thanks
 

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feeding your habit
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you need to figure out why it's running for shit....

have you checked codes?

do me a favor, since I lost track... list your motor/ecu status (usdm cams? injectors? resistor pack? ignitor - do you have the condensor?).....

don't start fucking with idle, etc... that's not a fix, that's a bandaid. Stop with the damn bandaids and start with diagnosing problems.

why do you think it started running for shit when you hooked up the tach? Is it a NA tach or TT tach?

also, I'm glad you're not taking this as criticism.... you have a sweet car.... just want to see you do it the motor as nicely ;)



Thanks
-M
 

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Discussion Starter #12
98mkiv said:
you need to figure out why it's running for shit....

have you checked codes?

do me a favor, since I lost track... list your motor/ecu status (usdm cams? injectors? resistor pack? ignitor - do you have the condensor?).....

don't start fucking with idle, etc... that's not a fix, that's a bandaid. Stop with the damn bandaids and start with diagnosing problems.

why do you think it started running for shit when you hooked up the tach? Is it a NA tach or TT tach?

also, I'm glad you're not taking this as criticism.... you have a sweet car.... just want to see you do it the motor as nicely ;)



Thanks
-M

jdm motor with us harness, us ecu, us 550 cc, us igniter, efi reistor pack. usdm turbos, downpipe, etc. everything converted except cams.

have na tach but am using autometer tach instead of tt tach.
have not checked codes. i appreciate your help. i really do.
 

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You could reset your USDM, get rid of the tach, run the motor. Then pull codes first from your usdm ecu and write them down. You could also put in your JDM ECU and lose the MAF. Try running it MAP based first - eliminate as many unknowns as you can, the maf being one of them. Let me know what you find out when you do this.

Plugging in the tach may or may not have an effect. It is fed by the ignitor and if you pull the signal down somehow it can cause problems, I know when I did emanage ultimate it was pulling the signal down on the tach line and the motor would not run.

Loose the tach till you get the idle worked out.

Take off your IAC Motor and clean the pintle and the flapper valve. Ifyou haven't yet, do it now. Two bolts and two philips screws. Be careful with the screws, they are soft and the philips socket strips easy. Start by taking off the 2 bolts, disconnect the hose and cable. Then on the bench remove the two screws (press hard to save the philips part). Clean with a wipe. Also clean the valve that sits in the manifold behind the mount.

No problem on the help, the job you are doing is huge. I am at the end of doing mine (installing AEM now) and it was a MOFO. I did TT brakes, engine, 6 speed, resealed the motor, usdm cams, single turbo, walbro, etc, etc, etc.... it is a huge task.

By tuning issues, I mean you are going to have to deal with issues like running rich and things like 4" exhausts..... Running a 4" exh on your stock twins will probably put you past the limits of your wastegate, making boost control difficult. You might consider putting in an aftermarket cat to get some back pressure back into the system.... 4" exh is for singles, and only bigger ones at that.

-M
 

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doubt it.

unplug the coolant sensor.... your car should idle fine regardless of the cold temp.... cars start and idle in 10 below! What happened to your JDM ecu?

-M
 

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Discussion Starter #16
98mkiv said:
doubt it.

unplug the coolant sensor.... your car should idle fine regardless of the cold temp.... cars start and idle in 10 below! What happened to your JDM ecu?

-M
just bought longblock. got usdm everything.
 

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OK. Then reset the ECU, run it and pull the codes..... should tell you quite a bit.
 

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Now that you mentioned coolant temp sensor.......It has EVERYTHING to do with the car running good or like shit when you first start it. I know this first hand because I accidentally cut the wrong wire once and disconnected it. Car never ran right until I fixed that wire.

Definitely check that out. Also make sure all you IC pipes INCLUDING the actual intake that connects to the MAF. You can also attempt to disconnect the MAF and start the car in safe mode. That will tell you if there is a problem with the MAF.

Good luck.
Alex W.
 

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Discussion Starter #19
OVRBST said:
Now that you mentioned coolant temp sensor.......It has EVERYTHING to do with the car running good or like shit when you first start it. I know this first hand because I accidentally cut the wrong wire once and disconnected it. Car never ran right until I fixed that wire.

Definitely check that out. Also make sure all you IC pipes INCLUDING the actual intake that connects to the MAF. You can also attempt to disconnect the MAF and start the car in safe mode. That will tell you if there is a problem with the MAF.

Good luck.
Alex W.

how do i do safe mode?
 

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Basically just unplug the Mass Air Flow meter (MAF). That's safe mode. It lets the car run off the map sensor. It's not meant to run like this normally so you won't be able to boost or even get WOT, but if it idles and runs normal with the MAF unplugged then you have either a serious vacuum leak or your MAF sensor is no good (less likely).

Good luck,
Alex W.
 
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