Car wont turn over after swap!
 

Alright so first thing is details. I just swapped a 7mgte into my 7mge supra. I have the same year ecu with harness and motor but my body is 88 which doesnt make a difference since pre 89 are the same. The harness was for a automatic and decided to use a R154 tranny. So I researched how to bypass the nuetral system and spliced the two wires off of one round plug together.

Things I havent done yet is put the Turbo tachometer in yet and thats the only thing. I used the original NA starter and figured I didnt need to change that out. I also got a 100 amp fuse for the alternator, is that the right one or is it a 80 amp? originally there was just a wire connecting to each side to get power to the alternator. There is two small plugs from the harness next to the ecu that dont have a place to pug into, one is black and the other is yellow. And I havent conneted 3 wires that go to the water neck, they are the ones that slide onto the metal like the fan shroud and coolant temp switch. Other then that everything is connected.

There is power because I replaced the battery the other day.

Any and all sugestions are welcome to what the problem might be?

what happens when you turn the key??
plz explain...

because i pulled a 7m engine recantly and forgot some starter wires...

When I turn the key to turn it over theres one click noise coming from where the ecu is, which was kind of strange and I couldnt pin point where exactly where it was coming from.
Also the fuel is going cuz I hear a spray and I have a little fuel leak which Ill fix as well as a small coolant leak on my floor.

you might want to unplug the fuel injection until the starter atleast starts kicking, so you don't flood the cylinders. Take a vantage or something to the starter wires and make sure you're getting power, you can do an amp test by cranking the started while having the leads in the proper position on the started case and on the big ass wire bolt attached to it, i think thats right atleast its been awhile.

okay. when you mean by unplugging the fuel injection you mean each wires to the injectors right?

EFI fuse should do it

What do you mean the efi fuse should do it?? explanation please?

Fix your fuel leak before going any farther.. safety first. Pull the little wire from your starter and have someone turn the key and check for voltage. Again while wire is unhooked from starter. Don't pull the efi fuse or u will lose power to your ecu the main brain of the efi system and that's why its powered from the efi circuit. Check your connections on battery and make sure your ground is hooked to the block below intake manifold. Let us know

your EFI fuse is for your injectors, a bad one basically tells your injectors to stop working and then in return your car is starving for gas. a good one just does what its spose to..

you have 2 fuse box, my EFI fuse is located under the hood on the drivers side, its a 15a and is labeled "EFI"
check the one under your hood, if not there, check the one in your car by the drivers kick panel

once you find it pull it out, if its good keep it, if not go get a new one..
then just turn your ignition to see if you get acouple clicks from the starter..nothing? then take a amp to see if your even getting power to it...
maybe you missed wires..
check the amp level any way, i think you should have 1.5? idk im not sure...
tell me if you get it working..

when i did the swap same clicking happened it was wierd.

A.starter was hooked up wrong
B.battery was dead (check that you have proper voltage.)

you need air fuel and spark.
your missing one...

thats why i have a fire extinguisher!

Engine not turning over means that the starter is not turning the engine. If it turns over but doesn't run, then it's not firing.

Your ecu will not affect the engine from turning over.

If it's not turning over, check your connections on the battery. Make sure they're tight. Make sure there is no corrosion present. Make sure the connections at your starter are tight.

If the above checks out, do this:

Also check that you have 12 volts DC at the large starter lug (where the big wire connects) at all times, regardless of key position.

If the switch leg (little wire) has no voltage with the key in the "Start" position, then double check the neutral safety switch bypass you did. I can't remember if these cars have a starter relay, if they do check that. Also may want to make sure your ignition switch is working, as well as the ignition fuse (once again, don't remember if these have that).

If there is no 12V DC at the main lug, you have a break in the wire or a bad connection. Check the entire wire for soft or hard spots.

FYI, you pull the EFI fuse so your car wont be spitting fuel into the cylinders while doing voltage and amps checks on the starter, pulling the EFI fuse will in no way hinder you from making sure your "starter" is working, go to google and type in starter AMP test, and starter voltage test to see what you need to do. "I AM IN NO WAY SAYING THE EFI FUSE IS BAD" Just pull it before you do cranking tests.

The alarm system can also disable the starter.

Okay so I fixed the fuel leak, just had to loosen the union bolt and tighten back on. I pulled the efi fuse so the cylinders dont flood. I checked voltage in the starter and there is power getting to the amp since it would go up to 400 then start at 0 and work its way up again. so im not sure what the problem could be for that. There's also alot of corosion in the wires so ill replace them anyways for future.

Also it never made a clicking noise, the clicking noise I was originally talking about came from the ecu area.

How can I check to see if the problem could be the alarm?

Which connection at the starter has no power, the little wire or the big one? If it's the big one, the only culprits can be a bad connection or bad wire. If it's the little one, the alarm is a possibility.

If the alarm is cutting out the starter, I believe you unlock the passenger door a couple of times with the key to disable it.

I unlocked and locked the passenger side and tried starting it and still nothing, but now the fuel leak is back so im gonna use some white plumber tape on the union. and im gonna replace the large wire from the battery to the starter hoping thats the problem.

So if the wires to the starter (large battery and small ecu plug) arent the problems, then the only thing causing the starter not to start is the ignition wiring?

If the fuel line fittings are taper thread, then the teflon tape will work. But, if the fuel fittings are flared tubing or a banjo bolt, the tape will do nothing.

As to the alarm, try unlocking on drivers door, passenger door, and hatch. IIRC, I had this happen once and it did matter which lock disarmed it?

You could remove the starter and do a bench test: Connect battery "-" to the frame and battery "+" to the large stud and see if it runs. Then you know if the starter works or not. If it runs, then the problem is either in your power connections to the starter, or, in the control circuit. The control circuit gets a little more complicated, hopefully you have a manual and/or wiring diagrams?

I don't recall that you stated the year of your car, but, I have manuals on 86.5 and could post diagrams if that would help.

Hope some of this helps.

Good luck!

Denny

My car is a 88, its in the start of the thread but the motor and ecu with harness is from a 87. I will check the hatch key lock to see if that works and if not I bought new battery cables to see if that works. I hope it works cuz I dont want to mess with the ignition wiring or circuit board.

Look man check the signal wire to the starter before going any further. It will tell u in about 3 minutes if your starter is gettin the signal to start. Do this before replacing or pulling anything... why must everyone start with the hardest things first. Why pull the starter when u can check it bolted right where its at.... if ur getting the signal and have a solid 12v to the big wire then its your starter.. if ur not then its something on the ignition side of things weither its the alarm locking it out or wiring or power issue. But check the signal wire first always.. its just as important as the main batt cable.

If you read what I posted above I did and the readings was read. It would start from 0 m V and go up to 400 m V, not sure what this means. but from what my brother-in-law thinks it might be charging up then dies or something, so it must be the battery cable right?

my car wouldnt start a day ago, jump it and got it to the shop,
alot of corrosion was on the battery cables..
took them off, pull the battery out, poured alil of baking soda and water(or coca cola will work) on the battery prongs, sprayed it down with water to get excess corrosion off..the loaded it up in my friends trunk to take to pep boys to get tested..

before i left for that, i got some coke and let the battery cable sit inside a cup full of it to eat the corrosion off til i got back

tested my battery, it held 12 volts which is need but lil to no amps..so it couldnt start the car...BAD BATTERY

i reccomend doing this before anything my friend...
if its a new battery then its the cables... replace the cables.. if it still doesnt work its the starter..
simple as that...
hope it works

Thanks! I'll do that tomorrow and hopefully it will work, other then that I just got to fix the coolant leak and the fuel leak that I thought I fixed but didnt :/ so every time i try to turn it over it leaks a bit. but i pulled the efi fuse so it doesn flood the cylinders.

IIRC, the efi fuse keeps the ignition from firing...we had you pull it in the first place just to make sure your starter clicks(pulled it so when you turned the key fuel didnt flow into the cylinders)it didnt click meaning there was not enough power to run it..
plug your efi fuse back in after you test the battery and clean your cables..
other words itll never start
i believe the efi does that..either way plug it back in after you clean and test the battery

helpful tips
 

the coolant isnt that tricky
go under your car and see if theres grease build up
if there is then power wash the bottom of your car and make sure theres no grease or any fluid for that manner..
wait a day and see if there is any trace of fluid..(on the frame, hoses, panels etc)
should be easier to spot it on the actually hoses and panels its flowing from then the spots on the ground haha

still cant find them i suggest following the coolant cables to find any cracks or nics in them.. if you found one replace the hoses..(with the correct hose!)
another way is to get a spray bottle, fill it with soap and water, shake it up and turn on your car*EDIT* and a/c full blast(ofcourse do this after you get it running) spray your coolant hoses and ac hoses to see if there is any leak...(the water on the hose should bubble up and pop a few times..just keep spraying if you think you missed one) this method actually works haha:nuts:

the fuel leak, im not familiar with that..
i believe i have a very very very very very very small leak but not enough for me to worry about now..
for me and congo to know..how do you fix and/or find a leaking fuel line?

It sounds like your talking about the big cable? I need the readings off of both cables please. 400mv is nowhere near enough signal to start it. If that's the big cable with that reading then replacing the cable will fix this. If its the little one then there is something wrong on the ignition side of things. 1000mv equals 1v by the way so u should have 12k if reading mv. 400mv could just be voltage noise. Or a bad ground. U hooked the ground up on the block right?

could be a bad battery..
battery with enough volts will turn on the components in the car but if it doesnt have over 450 amps it wont start the car..
(450 amps could be wrong, when i tested mine it read 212 amps and it was nowhere near good, soo maybe anything higher then 300?)

idk like i said just have pep boys test it.. if its bad then its the battery,
get a new one and if it still doesnt start the car its the big wire going to the starter.. replace that and should be running!

Ok, so I pulled the big wire off the starter and a plastic ring (seemed to be used so the nut doesnt touch the starter) broke in half and cant use it. is it needed or no? wanted to make sure before hooking the battery cable up.

The wire thats grounded to the block, it grounds to one of the two bolts to the left of the diamond like plate right? or does it grounded to the nut on the diamond like plate?

I know where the leaks are comig from, how do I fix hem without replacing the hose since its coming from the hard line that goes around the block, I can get do them if I just pull the exhaust manifold off and the intake plenum cuz those are the only two places that are leaking coolant. but the one under the intake plenum is barely dripping coolant unlike the other side whenever i try turning it over it drips like crazy!

We need to figure out if he is getting voltage before we try checking for amps.... mv is a way of checking for small voltage. And he said in the OP that he put a new battery in it.

And Congo u still haven answered three very important questions for any one tohelp u trobleshoot this problem. Let's focus on one problem at a time so we stay on track with the title of the post. The three questions are .....

the voltage reading on big cable.


Voltage on small wire goin to starter when key is being turned..

And is the main ground cable hooked up to the block.

I know u gave me A reading but didn't specify if it was the big or small wire.

just replace the hoses there is no permanent way of repairing it without getting new hoses..but this is off topic..

the reading off the big cable going to the starter? we need to know that
do you have a brand new battery? or like acouple months?

I did get a brand new battery, the reading is from the big wire coming from the battery. and yes I grounded it to the block but when i put the positive on the post it the wire I grounded to the block sparked both ends and melted some of the ground wire that was on the negative post.

It shouldn't do that...... so what I think is goin on is that washer that is on the starter caused the big or main cable to ground out on the starter its self. The 400mv u are getting is from a ground loop or otherwise known as ghost voltage so it has an open in the line. probably the fuse but possible ly the cable itself. So get a new fuse and get u a washer u can make one pretty easy out of any plastic but is try to go Atleast 1/16" make sure your connections are good and id check the ground wire for continuity to make sure it didn't break from bein shorted. Unlikey cuz the fuse is a lot weaker then the wire.. and this is assuming u had a good ground when tested the big wire.

Another way to check this is run a new cable straight from the battery to the starter and see if it fires.. with a new washer of course or you will have fireworks

So I went to schucks to check if the starter is still good, its bad, didnt do anything. there was still enough plastic so the nut wouldnt touch the starter. So im buying a new one fom them for 70$, is that good for a brand new one? toyota parts store isnt open to call and get a quote.

Ya that's a good price. I think Toyota. Is like 200

So I put the starter on and replaced the battery cables, still didnt turn over. I'm starting to get frustrated with this damn thing! I checked all my ground wires and they are all bolted on tight.

I dont know what else the problem could be besides the ignition wiring, how can I check to see if the problem is that or if its the clutch safety switch?

U check it for continuity between both terminals.

I don't think that is your problem though.. the problem lies on whatever wire u checked that had 400mv. If thats the big cable check the fusible link about six inches back from the starter.

If its the little wire then Chase it back all the way to the ignition connection.

haha i gotta ask this...

cars manual right?
i gotta ask the dumbest question before asking another..

your stepping on the clutch when you start the car right? lol
i gotta know

on the other hand...
do what travis said...check the continuity in both wires... if you replaced them..then check the volts on em..
search to find the "GOOD VOLT" numbers cuz i dont remember...
if its the big one..make sure its grounded correctly... the lil one follow it to the ignition wiring...could be connected wrong..
;)
make sure you step on the clutch! hahaha

I did step on the clutch. Also what do you mean by grounded correctly?? the ground wire that goes all the way to the block and on the side of the bay then Yes. Also I replaced the positive battery cable not the negative.

For the ignition wiring, where do I start to check the continuity? the plug that goes into the starter?