82rx7dream

trying to start my rx but will not go.
Start works outside of the car but as soon as I but it in it will not turn the engine over. The engine is not siezed and turns by hand easily. I had someone try and turn the key and start it today while I gave the alternator pulley a push.......when a huge spark down by the headers happened. I have a short somewhere and am now trying to track it down. I found a wire that goes to the harness from the alternator and we think that it is grounded out somewhere.
Any ideas on how to track it down ?
I am also guesssing that the starter will not crank over the engine because the ground and or short is cuasing the starter not to get enough juice?
Any thoughts on this situation is greatly appreciated.
Thanks

enigma32

I use an ohm-meter.

Probably an easy way to do it is with some wire, a 12v bulb, and a car battery.

Hook the car battery negative up to the chassis (or use the battery that's already hooked up to the car)

Then connect one terminal of hte lightbulb to the positive terminal of the battery, and the other terminal of the lightbulb to the wire.

Just poke the wire around until the bulb lights up. (it'll come on anywhere you touch the wire to something that's grounded-- i.e., the chassis or a short)
(so, touch it to an exposed part of the wire you think is shorted....)


If there's a short in the feed to the starter that's very *bad* 'cause it's setup to take a lot of current.
Electricity chooses the path of least resistance, so if you're shorted out somewhere it'll go through the short instead of the starter.... since it takes effort to go through the starter.

Hope that helps.

82rx7dream

Hey....thast a real good idea. I think that I have tracked down the wire. Its coming from the altenator.
I am going to open up th eharness it is in and follow it back as far as I can. Hopefully I can find the problem.
My brotherinlaw thinks that maybe a wire has melted inside the harnesss up against another one.
I doubt its something that simply.
I think that this may have happened when I took out a fried fusable link and replac ed it with a heavy gage wire.....STUPID me.Idiot lites dont light up any more either....I think that is and or might be traced back to my problem I am having with it not starting.

82rx7dream

UPDATE:
I tried for 7 hours today to try and find the short/ground!
I found nothing at all. I am still gettting the clicking noise from the starter as well as sparks at the starter assist motor cable and smoke from the throttle cable connection near the carb.
Can anyone help me out here, has anyone had this happen to them. I really need some help here guys.

Ultralights

sounds like the problem is in the starter or alternator area! is the starter wired up Correctly! there are the 2 big wires, and 2 more smaller ones! make sure they are on the right way!! or it will not start!

MyRxBad

I just sold him a perfectly good working starter, so that's not the issue. It may be the wiring to the starter.
Did you check you're battery cables? Positive one should be running directly to the starter.

I'd check the wiring on the alternator. Find a wiring diagram for it and make sure it's wired up correctly.

82rx7dream

Yeah the wiring to thje strater is good........positive cable to the the post that does not have the wire from the selionoid attached to it .
I removed the starter from the engine, grounded it and crank the engine over.....the starter turned no problem.
As soon as I try it in the engine I get sparks and or smoke in the engine compartment.
If tried disconnecting the alternator and still the same thing happened. I even tried unhocking the harness that feeds the all the sensors from the engine and still sparks and smoke.
So am I right in assuming that I have a wire or component shoting out and ground when I turn the ignition?
I checked the amps that the starter draws during my attempts to start it and I got around 50 amps....is that correct amperage?
Sorry for the rambling BUT I so want to figure this out!!

RotorMotorDriver

iTrader: (1)

Ok, well if the starter works outside the car, but not in, I would say that somehow the starter is shorting out when bolted in. I would start at the battery and double check ALL the wires. You should have one large wire from the + terminal that goes down to the starter, and another smaller wire that goes from the + terminal to the fuseable link block. On the - terminal, you should have just one large wire that goes to the strut tower and grounds, then down to the engine block and grounds.

As for the starter wiring, it should look like this when viewed from the rear of the car:



Now, from the alternator, you should have one charge output wire on the terminal with the nut, and a plug with two wires that go into the wiring harness to the choke and check relay). If this becomes unplugged or messed up, none of the idiot lights will come on when you first turn the key to the "on" position except the brake light for when the hand brake is set. If that looks good and you still dont have idiot lights, check the choke and check relay. Its on the inner fender on the drivers side between the strut tower and the windshield. Its a small goldish colored box with a plug on the bottom and it says choke and check or something on the top. Make sure that its plugged in well.

It could also be that your alternator might be fried and shorting out, or maybe that choke and check relay. I dont know what would be sparking down by the header or by the throttle linkage though... Keep up informed with your progess though, Ill try and help as much as I can. I wanna get that thing on the road!!

~T.J.

82rx7dream

Thanks for all your suggestions rotor motor driver!
I think I am going to try and work on it friday right through the weekend. I just dont know where to start. I am going to double check my starter wires. I think they are fine the starter crank when out of the engine but still wired up.
As for th esparks and smoke.......who knows. I guess the current is just findiing the path of least resistance.
I just wish that I could find the short/ground!!!
Like I said where the heck do I look now. There are no obvious wires cut or melted anywhere. I had some that were when I had someone do some welding close to the harnesses but it was a long time ago and those wires are fine.
Something is fried somewhere or maybe I am way off track.
Any ideas where I should start loooking now?

dnlloran

I find it easy to find a short/draw buy removing the negative battery cable from the battery then run a test light between the battery post and cable. If you have a short/draw it should light up, if it does then go to your fuse panel and start pulling one fuse at a time look at the test light if it doesn't go out put fuse back and repeat procees until the light goes out, this should give you the general location of where the short is. Wiring digrams are also a big help, when you locate where the short/draw is they will show you all the eletrical items running off that fuse, colors of wires and where they run, so you don't have to remove all the wiring out of one area, just the ones you need to follow.
D.

RotorMotorDriver

iTrader: (1)

Thats how I do it too, but I didnt mention it because it didnt seem to apply here because it only shorts when he tries to start it (right?). So, why would he sit there and hold the key trying to start it and shorting it out while hes pulling fuses when he could look under the hood and find the short because of the sparks, lol.

~T.J.

82rx7dream

I am thinking that the short must be an ignition on only thing.
Otherwise it would smoke as soon as I connect the battery. So the short must be in the ignition system somewhere or something that turns on only when the car is started because it does not smoke when the key is in the on position just the start position. That kind of narrows it down a bit. I pulled out all the fuses accept the engine one and tried to start it but still got the sparks in the engine compartment area.
I have been looking over the wiring diagrams also dlloran but have not figured anything out yet.
So to double check the starter wires, they go like this right.......
1. BIG positive to its own post on the starter
2. another wire connects to the post that also has the wire from the selonoid to the starter body
3. and a third one that connects via a connector.

Right?

RotorMotorDriver

iTrader: (1)

Woah there... That sounds like too many wires. Look at the picture above I posted, and if yours doesnt look EXACTLY like that, its not stock, meaning it might not be right. You should have only three wires as follows:

1. The big power wire straight from the battery to the starter post (the wire with the boot protector in the picture on the left terminal).
2. The ground strap from the starter housing to the solenoid (the terminal to the right of the positive terminal)
3. The small spade slip on connector in between the two larger terminals.

Make sure you have that. Anything else thats on the termials isnt stock, so disconnect it for now until you know what it does or until you have it figured out. Power also goes to the subzero start system when the key is in the "start" position, and thats over on the firewall below the washer fluid tank, so maybe that was sparking over by the header? So, to recap, from what I can recall of the stock system, you have power that goes to the starter, sub sero system, and the alternator when you turn the key to "start". I hope that helps some more. Good luck.

~T.J.

dnlloran

Sorry T.J. didn't know I was following a master automotive eletrician. The best advice I can give you 82 is to get a wiring diagram and trace your ignition system down with any luck you will find your short. best of luck and I hope no other eletrical items have been fried.
D.

RotorMotorDriver

iTrader: (1)

Haha, Im not a master automotive electrician by any means. I just happen to know some basics about how the car works. Ive been through the system before, both diagrams and physically, and worked with at least one end of every wire in my dealings with mine. Im basically a good educated guesser . Im just trying to sort out his problem so he can get his baby on the road .

~T.J.

PS - If you were being sarcastic as in trying to tell me that Im being overbearing and have to be right because its "my way or the highway", then I should mention that now that I re-read what I typed in my last post seems a little demanding. I was just trying to emphasize that the wiring should look just like what I posted for it to be correct. I didnt mean to make it sound like Im some kinda genius, lol.

PPS - Where in the heck is Waitsburg?

82rx7dream

Yeah rotormotordriver I onlyhave 3 wires, just wanted to make sure where they go. I have them correct. My alternator was wired funny , with that wire that was grounded to the motor(it was connected to a flat head screw on the back of the alternator).
I also think that since only one of my idiot light(brake light) comes on when I turn th key on MIGHT have something to do with my problem also.
This problem is running through my head at all times of the day. I am hoping that I will think of something to do that I have not already done. Better be some nice weather this weekend!

RotorMotorDriver

iTrader: (1)

Hmm...I hope you get this figured out. Im almost all out of ideas here . So it doesnt short out on any other key position except "start"? That at least narrows it down to those few circuits, but what could be causing something to short out I wonder? Do you get sparks everytime you try and start it, or what? Does it just not do anything now? Are there even any noises or anything when you try and start it? Maybe you can give me a little recap and try and include some more information? It might ring a bell or two about what you can try.

~T.J.

dnlloran

It is 20 miles east of Walla Walla, 89 miles from the Idaho state line, and about 30 miles from the Oregon state line. I'm at work and all my books and CD on the RX-7 are at home so I'm just going off of what I learned in school. Don't mean to step on toes T.J. just trying to suggest that there might be another problem besides the ignition system.
D.

82rx7dream

OK.
Quick recap....
Put fresh battery in car.
Accessories work(headlights ,windows, latches and stuff).
turn key to the start position and the starter clicks BUT does not turn the engine.
When the starter is clicking there is also small sparks in the engine compartment(battery side), as well as I tried to give the alternator pulley a helping "push" while someone tried cranking the engine. HUGE sparks down by the exhuast in the engine compartment.

82rx7dream

OK...let me tell everyone how dumb I am.
My cousin and uncle were over today and we started talking about the rx7. I told them my problems and everything and my cousin says lets throw a battery in and I'll give you a hand trying to figure out whats wrong.
He says have you got a good ground and everything. I'm like yeh look its solid. He says, well lets just try and reground the battery with some booster cables to a good ground.
SURE enough, starter is working. Take off the main ground that runs to the battery and oh yeah she is rusty as hell!!!
Clean up the connection, hop in the car and we have ignition houston!!
The car did not start but at least it was turning over.
No gas gettting to carb.....fuel filter was completely blocked. Replaced filter......lots of gas to carb BUT not enough to keep it running.
It runs when gas is sprawed into the carb but thats it.
Seems like the carb is all gummed up.
Any easy ways of getting it cleared out??
ITS ALIVE!!!

RotorMotorDriver

iTrader: (1)

MMO in the tank, and maybe some of that Amsoil junk that someone was raving about the other day.

~T.J.

82rx7dream

Yeah but how is that stuff going to even get to the carb to clean it if itys not even going through it.
Somtimes fuel comes out sometimes not. Usuallly after it runs for a bit, THEn some gas comes into the carb on the passenger side rear part of the carb.
I tried taking off the supply gas line and blowing in it. Seemed to help a bit.
Am I going to have to take apart the carb to clean it?