Still cant Rx7 to start PLEAAASE HELLP
 

Ok ive been trouble shooting my 87 Tii for over a month. I have spark, i have fuel, i have air. It turns over but doesnt even act like it wants to start.

HISTORY: I pulled the motor to paint the engine bay. I figured 2 days tops so I didnt bother labeling the the harness (bad idea i knew better). ended up being over month and a half before i could get it back in the car due to one thing or another. While the motor was out i did the rats nest removal. blocked off emmisions, painted the engine bay and i think thats it. I did have some issues finding where some of the plugs went to but i think i got them all worked out now. Car will not start. it did run prior to pulling motor. Any Ideas where to start? I would greatly appreciate help on this for i miss driving my car. (ive been stuck driving my STI hehe) but i really miss the rotory. thanks

AFM plugged in?

yup and tested it as well just to make sure it was good

Did you unplug the harness from the ecu? Maybe you missed a plug somewhere.

yes when i pulled the motor i unplugged ecu and pulled harness and motor at same time. i believe there are 4 plugs that i had to unplug under the dash which i did plug back in. but just for grins ill go double check them now.

Did you check fuel going into the rails or coming out the injectors?
Check your timing. Especially if you removed the crank angle sensor.

fuel going in and out -YES
injectors-NO cause i havnt pulled the UIM off yet i was trying to troubleshoot everything else first. I do smell fuel occassionally coming out of exhaust. ( not flooded, i have deflooded it)
CAS- i never removed. now that i think of it i havnt tested to ensure its good. Ill try that as well

Use a test light with an LED, and check for injector pulse. The ECU applies +12v switched power to the injectors, and pulses ground through drivers. You'll need to hook the test light to 12v and probe the injector wires with the test light.

I had a no-start with my NA once that I almost couldn't figure out. Turned out that there was a large rubber hose going to the intake snorkel that was loose, allowing a significant amount of unmetered air to enter the engine. Check for leaks around the rubber TID (pretty prone to cracking).

One last thing. The emissions harness is 24 years old. It's been subjected to heat, cold, rain, grease, etc. for a long long time. My coolant sensor a few years back wouldn't read, even after replacing it. The connector wasn't broken on the outside, and was fully plugged in. The wires had come loose from the connector just enough that they wouldn't contact the prongs on the sensor. Since it had that little rubber thing on the back of it for Mazda's pathetic attempt at weather proofing ONE sensor connection, I couldn't tell it wasn't plugging in all the way.

Just food for thought :)

Make sure the coils have power on the B/Y wire w/key to on. If they don't then perhaps the ground from the Main Relay which attaches to the fender just below and to the side of the trailing coil is not grounding properly due to the new paint getting in the way and preventing the ground block from making proper contact w/the fender body.

If you are getting spark while cranking, your CAS should be working. If you have fuel, spark, and air, then it comes down to timing and the air/fuel ratio. If you didn't touch the CAS, then it comes down to the afr. It would have to be way off one way or the other to not even start. Most emissions removals get rid of things that add air during starting (AWS and BAC), so make sure your throttle plates are cracked and it is getting enough air. Or try starting fluid to get it running and troubleshoot from there.

did that this morning. even sanded down to the metal by the ground

Ill try starting fluid. gota get some from the store next time im there.

add to info: when removing the motor the wire on the o2 sensor got cut in half. will the o2 prevent it from starting? or just run like garbage?

It shouldn't prevent the car from starting.

If working properly then the Main Relay should click w/key to on and both the B/W wire and B/Y wire coming from the 4 wire plug of this relay should have battery voltage. The check connector w/the B/W wire located near the leading coil is a place to check for voltage w/key to on and this wire powers up the ECU.

it clicks and has power

ok so i decided to start over and go through the troubleshooting list in the FSM under the "wont start (cranks fine)" section. I am currently checking the coil w ignitor. When I check the (BY) wire to a good ground i get approx 11.9v. if i go from the (BY) wire to the (GY) wire on same plug i get approx 7.0v Should i make a ground from chasis to the (GY) wire to see if its not enough spark. I havnt rechecked the other coil yet. Should i reground it (assuming the (GY) wire is the ground. Thanks

cancel that. I relized the GY wire is the trigger not the ground.

The car only needs the leading coil to fire up the car. W/key to on the G/Y wire should have 5 volts then 0 volts in a repititious manner as the car is turned over "by hand," which can be done by rotating the alternator pulley.

ok so a few minutes ago i sprayed some starting fluid into the throttle body. It started for about 1 second then dies. it was rough but at least i know i do have spark. Does this give anymore clues on where to go. ive tried the deflooding procedures many times. so i dont think its that.

hey you checked your timing.. i know it doesnt start but i did a motor swap once and same thing it would run on starting fluid but that was it.... when i checked my timing i could not see the timing mark, turned out i had the CAS plugged in backwards causing the timing to be 180* out. so just check the timing to see if its close to TDC while cranking... and if it is plugged in backwards you still will have spark just at the wrong time so check this

i didnt mess with timing when i took the motor out. but i will check it just to be sure. im just wondering also if i didnt put something back on or something when i did rats nest removal. ill check timing though thanks

Can you keep it running for a little by spraying more fluid into the intake? If so, you are adding 'fuel' and are running lean without the fluid. Look for vacuum leaks.
Can you start it with the AFM unplugged and fuel check coupler jumpered?
How about with the TPS unplugged? Just trying to revert to as many 'default' settings as possible.

ya its not that you change the timing its that the CAS plug is part of the harness you would remove to pull the motor

ok went out and retimed it. it looked like it was good when i pulled out. just to doublecheck i did it correct. looking from front of car i lined up the notch to the right on the pulley to the needle on motor. pulled out CAS and aligned the dot with the notch on CAS housing. put back in and tightened up. correct?

still nothing. i may call autozone and see if they have a new set of plugs just in case all mine are fouled from flooding. weird thing is it wants to start with starting fluid but not on its own with just gas

Try disconnecting the plug to the fuel pump and then follow that with trying to use starter fluid but do it a few different times in series and then reconnect the fuel pump back up. If your engine is indeed flooded then sometimes it requires the above to clear all the excess fuel out of the rotor housing. If you don't disconnect the fuel pump when adding starter fluid then you risk flooding it even more than it possibly is already.

will do once my battery recharges a bit. Also is there a way to adjust the tps without warming the car up. perhaps that may be an issue as well. Hell IDK just frustrated at this point. ive driven the car 1500 miles in 2 years. i just want to enjoy the car for a bit.

To adjust the TPS you would press down on the lever below the thermowax so the roller pin releases from the cam so the primary plate is as closed as it goes and then adjust the TPS. You also might want to rely on jump starting the car so the electrical system is getting enough juice as opposed to relying on a recharged battery.

ok TPS was way off. but i figured that. car still no starty. im gona leave it for a while before i roll it down a hill. and to let the battery charge overnight. its been cranking a lot today and has weakend. but so far:

1. TPS adjusted (to best i can without car warm)
2.Timed properly
3.has spark or wouldnt want to start with starting fluid
4.deflooded 10000x
5.checked maf
6.checked resistor
7.checked relay.

WTF am I missing? sorry just cussing at the car and myself

ok just to make sure fuel lines are in the right order ( which im sure they are) the one from the fuel filter goes to lower fuel rail and other goes to upper fuel rail correct?

My American NA engine has the fuel line going to the top line and the return line is connected to the lower line. JDM's are reversed.

About the fuel lines...

https://www.rx7club.com/showpost.php...51&postcount=6

ok went to wally world and got a few cans of starting fluid. came home hooked battery back up. sprayed some fluid in and unplugged TPS. started up and ran for approx 5-7 second then died. Im assuming due to being out of fuel (starting fluid). give any indication as to what that could be? Ill try plugging the TPS back in and see if i get same result.

Are you sure you have the fuel hoses hooked up correctly? A simple way to check would be to disconnect the end of the return line hose closest to the firewall and place the rubber hose end into a jug. Then turn the key to on. Then jumper the fuel check connector and the jug should quickly fill up w/gasoline. If it doesn't then you either have the hoses connected improperly or their is blockage somewhere in the fuel lines or the pump isn't pumping.

ya i double checked them this morning. the line from fuel filter goes to lower fuel rail------>upper fuel rail------>to hard return line by firewall

im going to run and put a coulple bucks work of gas n my gas can and add some gas just in case. The gauge does say "E" but should have enough in it. but just in case im going to run and get 2 gal worth. If i was to be out of gas this whole time id start a thread so all of rx7club could flame me without a suit on. lol but the plugs are wet everytime ive pulled them

Just check for proper fuel flow as suggested and this will help eliminate certain things.

ok i diconnected the return line. cranked it over and fuel came out. Hooked it back up. It has to be a fuel issue. cause when i spray starting fluid in it starts for a couple seconds. then dies once its out of starting fluid. I just cant figure out y it wont burn the gas the same way.

At the smallest plug to the ECU are 4 Green wires. The LightGreen wire (pin3E) and the LightGreen/Black wire (pin 3C) should have battery voltage w/key to on and w/key to start the voltage should drop. If the voltage drops then the primaries are receiving the ground signal and should be firing if the B/Y wire that powers the injectors has voltage w/key to on.

ok i went and tested the wires:

3E=0 when key in on pos. and roughly .40 when cranking motor
3C=12v when key in on pos and 8v when cranking.

ok well ya i had the same thing with starting fluid and mine was timging related...anyways, im going to go ahead and assume when u took your harness out that you marked each injector plug and injector so you knew which one went where correct?

back to the basics you have fuel, have you used a fuel pressure gauge to see what its really seeing for pressure? spark we know the timing is correct and it is infact firing.
you have tested your air flow meter and know its working.

next i think would be to check fuel pressure and also check to see if the injectors are
firing

ok well u may be on to something with plugs on the injectors. as stated in original post i didnt label the harness. so there is a good chance that maybe the injector plugs may be on wrong. i remember checking it prior to putting on the manifold but it would explain it not starting unless using starting fluid. but flooding everytime i try to start it as normal.

anyone have a link to which wire colors go to which injectors?

3E should test out just like 3C so something is wrong there.

Any suggestions on how to fix? ill go retest them as well jst to be sure.

ok just restested it and same result. 3E was 0

3E is the front primary so if it has a ground then it is open w/key to on and would likely be flooding the front rotor. The Light Green wire at pin 3E gets its battery voltage w/key to on from the ECU so that might be the issue. So disconnect the small ECU plug housing this wire and see if you can take the reading w/key to on from the ECU's pin 3E itself to see if there is battery voltage or not.

EDIT: Also make sure the wire above is not pulled back in the small ECU plug and not making proper contact w/the ECU.

there was very little battery voltage. .4 volts. it was the same all the way across the pins though. the plug still had voltage with key on except 3E.

Which pins are you talking about and did you try to take the reading from the ECU itself and not the small plug?

From the FSM:
Front Primary=Light Green 3E
Rear Primary=Light Green w/Blue Stripe 3C
Front Secondary=Light Green w/White Stripe 3H
Rear Secondary=Light Green w/Red Stripe 3F

With the key on, you can ground each of those wires and listen for the injector click as it opens and closes.

basically i went through the same process i went through earlier just without the plug. i just tested the ecu with no plug.

ok i read the same thing but my wire colors are brown not green