my hemi

Im working on a 91 z28 350 tpi car I changed the valve covers and now the car wont start wont crank...when I turn the key the lights don't even dim....this is what I checked...power to the battery thru the fusible link to the starter has power to the big side...no power to the little side...has power to the igniton switch going up to the enable starter relay has no power going to the neutral safety switch I tried jumping the enable switch out using the 2 thicker wires when I turned the key the jumper wire smoked got hot...also I even tried using a resister to match the key to bypass the vats that didn't do anything either IM LOST all I did was replace valve covers gaskets now the car wont start...what else should I check thanks !!!!!

RedLeader289

iTrader: (2)

Did you check all your grounds? The only thing I can think of is that in the process of taking the covers off/putting them back on maybe you pinched something or knocked something unintentionally.

my hemi

I looked and looked i didnt see anything that looked pinched?....where are the grounds i will recheck again...but why when i jumped the enable relay the wire got hot and started to smoke....this is weird...

RedLeader289

iTrader: (2)

Should be one on the back of the block, one on the front...some could have been added/removed if you aren't the original owner.

Does your battery have sufficient charge?

my hemi

This is my wifes car she has had it 22 years..never been tampered with...lol...yes the battery is fully charged...when you turn the key notihing...all the light work...dont even dim...its like there is no starter there...i checked power to the starter i have it on the big terminal...i checked the ignition switch has power i even tried to put in a resister in the vats to see if something was broke in the column nothing...i did trace power to the starter enable relay...one side has power the other didnt so i jumped it thats when i saw smoke...and that wire got hot...weird unless its a ground power and the reason it smoked it got double power??? im lost

RedLeader289

iTrader: (2)

Maybe the starter has gone out then. If you have power everywhere else but the starter isn't engaging then that's what you're left with.

my hemi

Well im going to try and jump the starter to see going to hit the larger terminal to the little side see if it engages if it does then something has to be broke somewhere....

Steve Mack

iTrader: (5)

If it ran fine before you changed the valve covers it has to be a pinched wire or some other wire got disconnected.You could have accidentally shorted a wire. Check your fuse panel for a blown fuse.Don't start jumping wires or you might start burning up other components .

my hemi

I checked all the fuses... I know the crank fuse isn't getting power when I try to start the car..i traced the power into the car the ignition switch is getting power the starter enable relay is getting power on one side...neutral safety switch isn't getting power...the car has power to the big side of the starter...im guessing I need to try to jump the starter to see if its the starter that's the problem...like I said I have the book on the car FROM GM I traced wires and followed wires that should have power they do ....also the ones that need power some do some don't....this is weird...

thtanner

iTrader: (1)

I had a starter fail recently (working one day, completely dead the next), but the lights would dim.

my hemi

Yeah nothing dims when we try to start it....that's why I don't think its the starter....not that im not going to try and jump the starter with a screw driver to see if it engages...im also going to to have my wife turn the key to try to start the car while I check the small terminal on the starter see if power is going there....

greenyone

iTrader: (1)

You said you jumped the starter enable relay? The one behind the drivers foot well kick panel?

my hemi

Yes I traced the wire to the relay the one in the kick panel I had power going in none coming out so I jumped it when I did the wire got hot and stared to smoke...so I pulled it out super quick....oh the car didt start then either tho the lights did dim when trying to start with the wire jumped..im lost

greenyone

iTrader: (1)

Was the wire getting hot with the ignition switch on or off?

my hemi

it was when I was turning the key to the start position is when it got HOT..it was HOT fast....

greenyone

iTrader: (1)

Well the good news is your ignition switch seems to be working. Bad news is something down-stream of that relay has gone wrong. I'm betting that whatever is causing those wires to get hot probably cooked that relay. So you may as well throw that in the shizzle can. I'd pop out that starter and have it bench tested and clean up your grounds real good.

my hemi

ok I wonder if I can check the starter out but jumping it with a screw driver...or try to have my wife turn the key and see if I get power at the little wire on the starter?

greenyone

iTrader: (1)

I would guess you have a short to ground in the solenoid on the starter. Or possibly a locked up starter motor. Either way, if you are going through the trouble of getting under the car to jumper the starter you may as well just swap out that screwdriver for a socket wrench and yank it out of there to be bench tested safely. Don't forget to disconnect your battery if you do decide to pull it.

my hemi

Ok so let me ask you this...if i have my wife try to start the car while im under it should i be getting power to the little terminal?....or if the starter is no good i wont get power to that little wire?.....

tealman92

I bet the starter took a crap and took out the relay as well. So pull the starter and bench test it and remove relay and replace. You already know no power is going past the relay be cause you by passed it and it started to smoke so you testing for power with your wife turning the key wont help because something beyond the relay is shorted which shorted the relay. Its very clear.

my hemi

Ok but if the relay is shorted and i bi pass it what past that is shorted the starter? should i just replaced the starter then?...so your telling me if i go down to the starter and have her turn the key i wont get power to the little terminal anyways because the starter **** the bed lol ?

Steve Mack

iTrader: (5)

Are you getting any clicking noise when you turn the key to the start position.If so the starter solenoid could be bad or as mentioned above the starter gear could be wedged in the teeth of the fly wheel.Your idea of getting under the car and having tour wife turn the key to the start position is a good one.You can check the small wire for power and also check for the clicking sound.Also as mentioned before bench testing the starter is a good idea.Or get a remote starter switch from the parts store.They're not that expensive.The old screw driver jumper trick will also work.You should get power to the little wire even if the starter is bad

my hemi

Ok when i turn the key to the start position NOTHING happens no noise no dimming lights nothing..i know for a fact i have power to the large terminal of the starter...i checked that but i need to see if there is power to the little terminal when she turns the key to the start position..NOW if there isnt could that purple wire be broke somewhere? If so i can i run a new wire to where the purple wire goes to?...I have to see where that wire goes im sure its in the loom but maybe i can run a new wire to try to eliminate the problem?

tealman92

More then 1 person has told you to remove the starter and bench test it. You wont get any power to the starter if the relay is bad. You already tokd us it smoked when bypassed so what are you waiting for?

my hemi

I dont have a problem dropping the starter and going to go get it checked my problem is it doesn't make sense to me...how can the starter blow out a relay?...has power going in no power going out?...so what your saying the starter solenoid backfed to this relay blow it out and now the car wont start?...I would think that the purple wire got crimped or hit metal shorted something out..remember I changed the valve cover gaskets I was playing around with that big wire loom on the passenger side moving it around tugging on it...the car ran fine stared just fine before we did the valve cover gaskets So its blowing my mind that the starter just WENT..tome it seems like I broke a wire or shorted something out..so is it possible I shorted out the starter? is that what ever one is saying?....im trying to trace wires here it led me up to the starter enable relay has power going in none coming out..thats why I asked for help...if it is the starter great I would be happy with that....

funkdubie

Well...you can check the starter on the car by the old screwdriver method....that will tell you if it is the starter or something before it. As far as the starter relay goes...it is easy enough to check as well if you have a meter or you can simply bypass it the correct way...if it smoked...that was not the correct way. If the print i looked at is correct...you should have 2 yellow wires that are hot when the ignition is moved to the start position. One of the yellow wires goes to the coil, the other to the fixed side of the relay. On the other side of the movable portion should be a tan/white wire that feeds through your neutral safety switch. If the colors are right...you can jump either of the yellow wires to the tan/white to bypass the starter relay. This will feed through the safety switch straight to the small terminal on the starter which is the solenoid which has to be energized before your starter does anything.

Link to the print i googled. Copy paste should work.
http://austinthirdgen.org/mkportal/m..._continued.gif

my hemi

Ok I did bi-pass it right the relay has 4 wires going to it 1 thick yellow..1 yellow...1 yellow and black and 1 tan and white...I took the thick yellow and jumped that with the tan/white wire....IT SMOKED...so what did I do wrong? or is there something else wrong...ok looking up the schematics from the shop manual the thick yellow wire goes to thru the starter enable relay comes out tan/white to neutral safety switch...the thin yellow wire goes thru the relay coming out as black yellow to the VATS....that's what is for this 91 Camaro...we have the GM shop service manual...I think I hooked it up right....making me think its a crimped wire somewhere but I could be wrong...or maybe I did hook it up wrong????

Scorpner

iTrader: (4)

If you have a short then bypassing the relay isn't going fix that. You may burn out the wiring or start a fire though. When something smokes it means damage was done, you may be looking at replacing the wiring and anything in line with it. You can try taking apart your relay to see if there is any damage.

Disconnect the battery and troubleshoot using a meter on ohm or beeper setting. If you suspect a wire is shorted it will read 0 ohms (or very close to it) when measured against ground. You can try the key test that way as well.

I would not try bypassing the starter at the solenoid, if you don't establish a solid contact it will spark in your face, and if you happen to touch ground (in a very restricted space) you can electrocute yourself. It's only 12v but can involve an incredible amount of amperage which is the amount of current flowing through you.

A typical circuit involves components that provide resistance to the current flow, keeping it in check. A shorted wire bypasses the components which provide the needed resistance, and with an automotive battery you can end up with an extremely high current flow which can heat up, smoke and start fires. A good analogy of an electronic circuit is to think of it as water flowing through channels, and a short against an automotive battery would be like busting a dam far exceeding the rate of flow that the wires are designed for.

funkdubie

You have a wire grounded out most likely after the safety switch. Do you have a meter....if not..you really need one.

my hemi

Yes i have a mutil meter where should i check for a bad ground?

my hemi

Could the starter be the bad ground?....im lost here i have no idea how to find a bad ground...

Steve Mack

iTrader: (5)

I don't think you burnt out your starter motor.Maybe the relay on the starter?Get your test light out and check the small wire on the the starter relay for power when your wife turns the ignition switch to the on position.

my hemi

You mean the purple wire by the starter or the wire near the relay...i have power going into the relay nothing coming out...no power at the tan/white wire....which goes to the neutral safety switch.

funkdubie

Ok...put your meter on ohms...the little upside down horse shoe symbol...touch the leads together..it should read about 0.0 to 0.1. That is a dead short. Your ignition circuit is possible shorted to the car body/engine/negative side of the battery (all tied together). So...put one lead against the car body where the negative battery cable is bolted..the other on the wire you are checking ...it should not read 0. If it does..you have identified the problem. Then you need to find where that solenoid wire is grounded using the electrical print from your shop manual.
The starter itself could be grounding out internally but i have never seen one do that unless you smoked it which i don't think is the case. If you don't disconnect the small wires going to the starter and try to check it with the meter it will probably read something like 2 ohms which would be normal...but with the wires disconnected and checking the it should be much much higher...possibly the same as your meter reads when not touching anything with the leads which is infinity. Take 5 minutes and check a youtube video on using a meter on ohms scale...it will save you some confusion.

funkdubie

and you will never have power coming out until the ignition switch is turned to the start position and that relay picks up.

my hemi

OK with the starter enable relay plugged in and the key turned forward to start position I get NO power to the tan/white that's why I jumped it in the 1st place because I didn't see power going thru the relay I jumped it turned the key and that's when I saw smoke....now if its not do with the igniton circuit how can I ohm it out if the battery ground is outside the car lol....

Scorpner

iTrader: (4)

IMO, you need to stop and understand the terminology and what you are actually measuring. Applying power may further damage your wiring.

These are two completely different things. You are looking for a short (to ground), not a bad ground.

• A “wire grounded out” is the definition of a short circuit because the wire makes contact to the frame(ground) before it's supposed to. This would be something like a pinched wire to metal on the engine block or frame of the car.
• A “bad ground” is actually an open circuit because the wire that's suppose to go to ground is not making proper contact.

In electronics you have a positive and negative at the start of a circuit.
The negative side is always “grounded” to the frame, engine block etc. (Ie. The entire body), otherwise known as the common ground.
When you diagnose with a meter most everything is referenced to the same common ground which is the frame/engine block etc.

• A meter set on ohms measures the resistance against ground (Car battery must be disconnected.).
• A meter set on volts measures the difference in voltage, in this case, in reference to ground.

When something shorts out, the wiring contacts the ground (frame/engine block) prematurely. There is no resistance and because of that current becomes very high resulting in smoke.

The relay may have been faulty or damaged previously from excessive current. The relay not allowing current to flow through it is known as an "open." If you were to take the relay apart, you might be able to visually see if this is the case.

• If the wiring coming from the relay to the starter is shorted, then bypassing the relay will only reconnect the short you had before.

• For a short: the output wire from the relay - to the frame or engine block, would measure close to zero ohms (as mentioned). As mentioned, the body/engine block etc. is as you say the "battery ground" regardless if the battery is actually connected or not.

Ohms are measured with the battery and switch/relay disconnected. A meter set on the ohm setting provides it's own voltage to take measurements, therefore you must disconnect the car battery.

bigal55

iTrader: (1)

You can't test the starter circuit that way without the battery in the car. What you can do is measure resistance from the purple wire on the starter solenoid to the frame or the battery negative cable. You don't need the battery in the car to test for a short between the negative cable (or frame) and any wire in the car. You said you had power at the starter relay signal side from the ignition switch so you are good on that side of the relay. If you show 0 ohms when testing between the purple wire and the frame then that is your problem. I don't have the circuit diagram to look at but the purple wire going backwards from the starter goes through the neutral safety switch (automatic transmission) or the clutch switch (manual transmission). Your starter relay is probably bad now and should be replaced, but you need to find the short circuit on the starter side of the relay. HTH!

bigal55

iTrader: (1)

Very good explanation!

my hemi

Thanks for that info I do have 2 questions..... 1 when we tried starting it my wife felt the relay clicking...does that mean its ok or shot or can you not tell.`...and 2 so I understand disconnect the battery which cable pos or neg...and then pull the purple wire off the starter measure it to see if I get 0 that means its shorted/broken?...now can I run a new wire from the starter to the neutral safety switch and basically bi-pass that purple wire totally?...

Scorpner

iTrader: (4)

Thank you!

Scorpner

iTrader: (4)

You may not be able to tell. The relay has a magnetic coil inside that energizes when current passes through it. That's the clicking you hear. The coil is only on the ignition (key) side, and not on the starter side if that makes any sense. So if it burned out (an open) on the starter side, the ignition side could still be unaffected. The link below shows the low side circuit (ignition) as #1, and the high side circuit (starter) as #2. (Should be an animation of it operating.)
http://cdn4.explainthatstuff.com/how-relay-works2.gif
From here: http://www.explainthatstuff.com/howrelayswork.html

I always disconnect the negative side of the battery first since the metal body surrounding the battery is negative also. If you wrench on the positive connector and touch the body, it can short to any metal that it might touch. When you wrench on the negative side you would only touch the same polarity.
Be careful that the cable doesn't lean back into the battery after it is disconnected. I have one that I have to hook off to the side to keep from doing that.

I've been an electronic tech in the computer industry and not so much on the automotive side. From my previous experience with that, I would say not to move or unhook anything, but instead check the wire as it sits. For example if the wire in question had rubbed through somewhere and you moved it while unhooking it from the starter you may lose the chance on confirming the short. Right now you want to confirm the short, and if you move the wire and it doesn't ohm out as expected, then you'll be back to square one. Also, if you ohm it out and find the short, then you have the option of unhooking the wire from the starter and then checking each individually.

If you run a separate or replacement wire make sure it is at least the same gauge and/or rated the same.

my hemi

Ok anyone know where to get this relay having a hard time finding it....


ALSO what I meant was when checking the ohms on the purple wire do I leave the battery hooked up or disconnect it? thanks

Scorpner

iTrader: (4)

You need to disconnect the battery when checking ohms, the meter supplies a small amount of voltage of it's own.

my hemi

Ok thanks I will be checking it tomorrow I will post back results...I also ordered a new relay that's on its way....

Steve Mack

iTrader: (5)

If you ordered a new relay pry the black cover off the old one with a small screw driver and see if there are any burnt wires

my hemi

Ok jacked the car up and I ohmed the PURPLE wire well it isn't shorted it reads 0.50 to 0.40 ohms...what else can I check...STILL no power at the tan/white wire any ideas on what else it could be???? starter NO good IM LOST here....

bigal55

iTrader: (1)

It reads 0.50 ohms to what? The frame? That means it is shorted to the frame. You should have about 0 ohms through the wire to its termination at the other end, neutral safety switch? You should have infinite resistance, or at least very high resistance from that wire to the frame.


When explaining what you have tested, be very specific about what you did to test the circuit. Saying the wire has 0.50 ohms means nothing until it is referenced to some point, whether it is itself from one end to the other ( which should be 0 ohms ) or to a spot on the frame or maybe the negative battery cable ( in which case it should be open circuit or infinite resistance ). If we don't understand what you are doing, we cannot help and will lose interest in trying to help, so, in other words, help us to help you!

mk1431

always disconnect neg terminal automotive flows from neg to pos

my hemi

PER Funkdubie this is what I did...I disconnected both positive and negative cables at the battery I used the body ground by the battery on the right fender as ground...then using the ohm meter I went to the purple wire at the starter I saw 0.50 ohms....so by this the purple wire is shorted ?...so then why is no power coming out of the tan/white wire to the neutral safety switch? I can see the purple wire to the other side of the neutral safety switch being bad...or by the purple wire being shorted that means the neutral safety switch wont see power...so what is wrong I have to replace the purple wire to the neutral safety switch ???? thats why im lost I cant understand why I don't have power coming thru the starter enable relay but power to it...maybe I just don't understand the wiring of this car...but I would think it goes in series igniton switch...starter enable relay...neutral safety switch then down to the starter...thanks for any help....