MAPed Blue Top Swap, NOT staying running! Please Help?!

Iketani Joined: 08 Apr 2008 Posts: 32

Okay.. This is completly melted my brain trying to figure this out.. I have a AE86 GTS and the Motor was toast so I pulled the USDM motor/Tranny/Engine harness/ECU, and all.. Now I got a Japanese blue top MAP sensored motor & T50 Tranny /harness/ecu/ Gauge cluster the whole nine yards. Now.. After replacing the Dizzy and having to buy a igniter, We got it to start up and Idle but after idleing for about 20 - 30 secs it dies. instantly dies if you press the gas pedal... My thoughts is its not getting the right voltage to the 4 main injectors and its only running off the cold start injector till the primer fuel runs out?.. Is there some type of wiring I need to do? Im so confused..... Can anyone help me out please???

Also take note that I have noticed there is a black sqaure like plug that sits on the fire wall in the engine bay. One half of the plug is connected to the engine harness the other half looks like it goes into the fire wall and splits into the drivers side finder ( LHD )

Now.. on that plug on the Japanese engine harness side there is a Yellow ( Main injector power wire?? ) in the center the USDM side of the plug has nothing there.. I did jump the yellow wire to the black with orange on the engine harness side and it seems to get it to idle as stated before. Other wise it wont really idle at all.. Not sure if this is how that is supposed to be hooked up. I also tapped in the Black with Red wire that looked to have been cut on the engine harness ( Around where the igniter plug is ) it has one wire and a small black plug. I tapped that into the black with orange so that it gets power when the key is put into the On position.. If any other info is needed let me know. Im just so confussed as to why its not working........ Shocked

Im soooooo Confused!!

Posted: Wed May 07, 2008 6:37 am Post subject:

Pictures of the connectors in question might help..cause it's a bit difficult to follow.

Posted: Wed May 07, 2008 7:44 am Post subject: We have the technology :))

Cold start injector only runs while cranking, so engine will fire and then
die quickly... after 2-3 seconds. Faster if you open the throttle Puh

If the big square plug is disconnected, you can jumper 12 volts directly
from the battery to the injector common power supply. Sounds like you
already did that if the engine will idle for 30 seconds.

Now you need to check if you have low impedence or high impedence
injectors. From memory, I think high impedence are 12 Ohms and low
are like 2 or 3 Ohms. Low impedence injectors need an injector ballast
resistor installed to restrict injector current draw. Its a diecast metal box
about the size of an igniter, but with small cooling fins on the cover, and
less wires.

If you need one, but don't have it, the car will run poorly, or not at all Confused

Cheers... jondee86

Iketani Joined: 08 Apr 2008 Posts: 32

some photo's

do I ohm the injector plug? or the injector its self? or how do I do it? With power and key to on position?

If I do need it does anyone have a part number, or know it?

Posted: Thu May 08, 2008 11:11 am Post subject:

Just pull the plug off the injector and measure the resistance between
the two pins on the injector.

Cheers... jondee86

Iketani Joined: 08 Apr 2008 Posts: 32

Now.. from what I can tell I have the 2 ohm injectors. I have the Injector Resistor from the USDM car.. and after looking at the Resistor and the plug on the USDM engine harness I think that if I tap the blue and red wires together and then connect them both to the yellow on the Japanese harness.. Then the black with orange ( Might have been black with yellow. ) to the black with orange to get 12v with the key at the on position. It should in turn work or am I wrong?

Also Im going from what I jondee86 said in another of my posts of what the Injector Resistor looks like.

Iketani Joined: 08 Apr 2008 Posts: 32

Well at trying that it only seems to fire up for 3 - 5 secs.. I think I was over stating when I said 30 secs I think the max ever was maybe 10.. anyways. Maybe its now cause the timing might be off?

****Update**** I Moved the vac line for the MAP sensor to the throttle body where I had it looped before. And now as for the Injector resistor, I have the Blue and the Red tied together and tapped into the yellow. and then Black with Orange stripe to Black with orange stripe.

It will now start and idle up for a while maybe about a good minute or so and if left to idle it will die. OR any time you give tap the throttle or step on it at all it will kill over as well.. Is this a Timing issue or maybe fuel pump?... Or just not enough fuel pressure for some reason?

Posted: Fri May 09, 2008 12:11 am Post subject:

i would check the fuel supply,sounds like it could be a waek pump or restricted pipe

Posted: Fri May 09, 2008 7:05 am Post subject:

And make sure you got the sensors in the head connected properly, that has also been known to cause these kinds of problems.

Posted: Fri May 09, 2008 11:05 am Post subject: Chasing ghosts....

The solenoid resistor (injector ballast resistor) has one wire going in and
two wires coming out. Resistance between the wire going in and either
of the wires coming out should be 2-3 Ohms.

The wire going in should be connected to a 12V power supply that is ON
when the ignition key is ON. Each of the wires coming out should be
connected to supply 12V power to one pair of injectors.

The injectors are arranged in parallel connected pairs. So each wire out
of the ballast resistor powers two injectors, with the downstream side of
the injectors being joined together, and then connected to the ECU. One
wire (two injectors) to ECU pin 10 and one wire to ECU pin 20.

It does not sound like you have this wiring correct. Check it, change it
if necessary, then see how the engine runs.

Cheers... jondee86

Posted: Fri May 09, 2008 6:30 pm Post subject:

Doesnt matter how you connect the injector pairs, those two outputs on the ECU are connected internally on the ECU's pcb, so it fires them all at the same time anyway.

Takumi Joined: 30 Mar 2008 Posts: 215

You check your grounds on the ignitor or the intake manifold?

Iketani Joined: 08 Apr 2008 Posts: 32

Posted: Sat May 10, 2008 12:00 am Post subject: Do it once... get it right !!!

Posted: Sat May 10, 2008 12:14 am Post subject:

Ah, very good point about those resistors ending up parallel. That's something you shouldnt mess up, ECU's built for high-Z injectors dont live long if you use them with low impedance injectors.

May I ask how the car idles when it is started? If it runs like crap, then something is likely to be very wrong. If it idles smoothly, but dies when revving, then it might be a smaller problem altogether.
Also, put your nose next to the exhaust next time you get it idling.. if it smells pig-rich, you can assume it's not the pump that's causing you problems (unless the circuit opening relay is not working properly that is, but you can rule this out by just jumping a permanent 12v source to the pump).

Iketani Joined: 08 Apr 2008 Posts: 32

It will start and run( Idle ) fine sounds normal to me no sputtering or anything as far as I can tell. and it will run for a good minute maybe alittle more and then die. However this is running with the Injector Resistor wires tied together and then tapped into the yellow injector wire. I will rewire it as stated above and see if that helps...
But Ivan to answer your question it seems to be idling fine. It will idle at 1500rpm or so.. Not every time but some times it will sorta flux in idle like.. 1500..then drop to around 1400 or 1300 rpm and back up to 1500rpm kinda like a wah wah wah fluxing if that makes any since at all. Confused

But I think it started to do that only after I had started it and idled it, killed it and started it again and repeated while tinkering with it.. But in the long run it doesnt seem to bad while idling..

As I said before I will rewire it and post up later on if that helped or not.. Just a thought that crossed my mind.. It wouldnt have anything to do with the TPS would it? just thinking that maybe that is why it kills over if you try to give it gas.. but maybe Im over thinking it abit to much.

Posted: Sat May 10, 2008 12:06 pm Post subject: Fuel + air + spark = ?????

Hmmm.... there is one thing that might be worth checking while
you are under the hood. Pull the return hose off the fuel rail and
make sure there is fuel being returned to the tank when the engine
is cranked. Should squirt everywhere, so be careful !!!

Cheers... jondee86

Iketani Joined: 08 Apr 2008 Posts: 32

Posted: Sun May 11, 2008 12:17 am Post subject: No fuel... no go....

If the return hose is dry, you probably are not getting a proper fuel
supply to the rail. If there is fuel coming to the rail (pull one of the
hoses and check), then the problem may be with the fitting of the
pulsation damper (assuming that you have one).

The pulsation damper looks much like the FPR, but without a vacuum
hose. It attaches at the front of the fuel rail, on top of the banjo fitting
that brings fuel into the rail. Above and below the banjo fitting are
copper washers. One of them (the top one) is a thin washer with "teeth"
on the inside diameter. If this has been replaced by a plain washer
that is a close fit on the bolt, it can severely restrict the flow of fuel
into the rail.

If you don't have a pulsation damper, check for a blocked fuel filter,
kinked hose or flattened hard line. Disconnect the hoses one at a time
working away from the fuel tank, until you find the point where you
lose flow/pressure.

Cheers... jondee86

PS: Going down the shed to check some of this stuff now Puh

Iketani Joined: 08 Apr 2008 Posts: 32

Hmm This could be the problem! I think Im going to maybe just get a new damper.. What I did was replace the damper and the FPR with the ones from my GTS motor. However the GTS one was leaking alittle. BUT.. Seemed like It maybe made alittle difference. But however it was still killing over upon trying the throttle. The washer had gotten messed up when I took the GTS damper back off.. Do you have a pic of the ' Teethed " Washer that is supposed to be on there. I dont think that mine had it. ..

to me it looked like the Inside of the washer was flanged out on both sides but im not sure that is what you mean.. If you have a pic that may help.. Im sure If I can get a replacement damper at a autoparts store it will come with some but I want to be sure.

Posted: Sun May 11, 2008 2:57 am Post subject: Filing teeth :)

The damper might be a Toyota specific part, so probably easier to
just try and find a washer. I don't have a pic just now, but consider
a standard round copper washer. On the outside it is smooth like a
regular washer.

On the inside circumference, parts are cut away to about half the
width of the washer, leaving around six "teeth" or posts that serve to
locate the washer on the centre bolt. Fuel passes up the outside of
the bolt thru the cutaways in the washer.

This is why if you put a plain washer in there, that fits close to the bolt,
fuel can't get thru. The toothed washer still seals, but around the outside
edge.

If push comes to shove, you can probably file some grooves in
the inside of a standard copper washer... enough to let a bit of fuel
thru and prove the point. A few 1 mm x 3 mm notches would be OK.

Cheers... jondee86

PS: Did you change the ballast resistor wiring ?

Iketani Joined: 08 Apr 2008 Posts: 32

Okay I did wire the resistor up like that and it didnt make a difference then I wired it like i had it before.. same.. then I removed it all together and it was the same. So I left it off. I replaced the fuel pump and it seems to be alittle better but if I cram the gas pedal it will still bog down alittle. However if I just barely step on the gas i can get it to rev up to 5000rpm ( Might go higher but I stoped there. ) Also before It would only go up to about 2000 and then bog and die. ... Also there is still no fuel getting pumped back to the tank... I ran a new rubber gas line off the FPR and ran it into a coffee can and nothing ends up in there.. I did not find the said washer or anything like it with teeth cut in the inside diameter..

Im thinking that the timming is off or something.. i dont know.. Crying or Very sad

!!

Posted: Tue May 13, 2008 3:09 pm Post subject:

Either you dont have enough fuel pressure for the FPR to bypass some to the return line, or it is faulty. If youre sure your fuelpump is working, then where is all that fuel going?

Iketani Joined: 08 Apr 2008 Posts: 32

Posted: Tue May 13, 2008 7:22 pm Post subject:

Wish I could tell you, but my car is in storage 60 miles from home, and the one sitting in front of the house has nissan wiring.
That washer might be what you are looking for... does the little bugger stop the fuel from returning to the tank? In that case the engine will flood I guess..not too healthy for the fuelpump either.
Have you tried pulling the plugs right after it stalls? One look at those can tell you quite a lot about what the engine is doing (flooding, poor mixture, oil contamination).