Help! Wont Start

[gman1234]

I have an 1981 corvette that has been sitting over the winter and now will not start.The car ran fine before I put it in away.

The engine turns over and I get combustion (smoke out the exhaust)and in wants to start but when I release the ignition, it does not stay running. I need to leave the ignition in the start position to keep the engine running.

I have replaced the distibutor cap and rotor, had the carburator rebuilt, replaced the gas.

The wires are producing voltage to the plugs,
I am assuming that it could not be the wires or the plugs, as all of them would need to be bad.

Not sure what this can be, seems to me like it something electrical, solenoid.

Any help would great.

 

[GerryLP]

It could be your ignition switch. Touch above the steering column, and you can feel a metal rod that connects the ignition lock with the ignition switch. As you rotate the key, try to feel the rod moving (in a liner way) along the top of the column and towards the brake pedal.

If the rod is not moving approximately an inch total travel, then it could be in the ignition lock and its associated gear segment. If it does, it could be that the contacts in the ignition switch are perhaps corroded or (worse case scenario), they could be misaligned.

The worse case means a new switch. For the earlier posibility, try rotating the key several times from accessories to start. to allow the switch contact arm wipe away the sludge buildup.

GerryLP:cool

 

[gman1234]

Still working on trying to get corvette started,

I have re-built the carberator, changed all the spark plugs, Distibutor, coil, rotor, ignition module,

And it still will not start, I also provided a direct 12 volts to the distbutor in case it was the key switch.

When I turn the key, the spark plug is spraking. The car turns over and I get some combustion wen the key is in the start position, I can also rev when in the start position, but as soon as I let the key go, it turns right off.

Please, help, if get spark, fuel, what else could I start to look into,

 

[BigJimZ16]

Still working on trying to get corvette started,

I have re-built the carberator, changed all the spark plugs, Distibutor, coil, rotor, ignition module,

And it still will not start, I also provided a direct 12 volts to the distbutor in case it was the key switch.

When I turn the key, the spark plug is spraking. The car turns over and I get some combustion wen the key is in the start position, I can also rev when in the start position, but as soon as I let the key go, it turns right off.

Please, help, if get spark, fuel, what else could I start to look into,

Two ideas, one the ignition switch itself, the other is the starter solenoid which has the source for ignition power on it( the 3rd wire).

 

[djsroknrol]

The engine turns over and I get combustion (smoke out the exhaust)and in wants to start but when I release the ignition, it does not stay running. I need to leave the ignition in the start position to keep the engine running.

Sounds like the ignition switch on the bottom of the column. That switch is one of the more complicated switches on a car and being a mechanical switch with that many contacts, when they break, they cause different symptoms. Mine went out one night leaving work leaving me electrical inside but no start and a strange feel (no detents and stiff feeling) when I turned the key.

Seeing that you have to hold the key, that switch has to be misaligned somehow, there's an issue at the connector or the rod is bent.

 

[GerryLP]

Still working on trying to get corvette started,

I have re-built the carberator, changed all the spark plugs, Distibutor, coil, rotor, ignition module,

And it still will not start, I also provided a direct 12 volts to the distbutor in case it was the key switch.

When I turn the key, the spark plug is spraking. The car turns over and I get some combustion wen the key is in the start position, I can also rev when in the start position, but as soon as I let the key go, it turns right off.

Please, help, if get spark, fuel, what else could I start to look into,

I still think it is the ignition switch. To check for misalignment, see if every position is off (for example, do you get power to gauges when turning it to "on"?)

But if is not that, then replace the switch. In 2004 the problem happened to me on the way to Cruise Fest (Auburn, Indiana). Except that in my case, it would not shut off the engine.

To gain access to switch, you have to lower steering column. And to lower steering column you have to disconnect rag joint between steering box and lower end of column. Not too bad of a project.

 

[gman1234]

Thanks,

I will go ahead and replace the ignition switch, I did bypass the switch, I ran a wire from the battery directly to the distributor, this way it always had power. But this still did not work.

I will try the ignition and let you know,

Thanks again,

 

[gman1234]

Well, I changed the Ignition switch, but it still does the same thing, no change.

Not sure what else I can look in too, I know its electrical, I have replaced everything.

Anyone have any ideas of what my next step, other than taking it to someone who noew much more than I do.

Starter Solenoid, though not sure what this woud do but engage the starter.

 

[GerryLP]

I have an 1981 corvette that has been sitting over the winter and now will not start.The car ran fine before I put it in away.


The engine turns over and I get combustion (smoke out the exhaust)and in wants to start but when I release the ignition, it does not stay running. I need to leave the ignition in the start position to keep the engine running.

I have replaced the distibutor cap and rotor, had the carburator rebuilt, replaced the gas.

The wires are producing voltage to the plugs,
I am assuming that it could not be the wires or the plugs, as all of them would need to be bad.

Not sure what this can be, seems to me like it something electrical, solenoid.

Any help would great.

I have not heard of an engine that keeps running only if keeping the key turned to "start".


Lets get back to basics.

You have the ignition wires connected in accordance to firing order (1-8-4-3-6-5-7-2)

The distributor's rotor (under the cap) it's about to align with the #1 electrode of the cap when the #1 piston is on its compression stroke

It's an 81 Vette, so the distributor is the 7-pin distributor (7-pin module under the rotor cap).

The 4-pin wire that connects distributor to computer is connected.

The TAN wire is connected to the "BAT' connector at the rotor cap. This is the switched wire that connects power to distributor to charge up coil.The brown wire for your tach is connected to the "tach" connector at distributor cap.

I presume you have not messed with coil, so don't have to check for center electrode under coil (it protrudes into center of distributor's rotor cap).

 

[Vettehead Mikey]

I have not heard of an engine that keeps running only if keeping the key turned to "start".

Pre-HEI cars have two separate paths to allow the electric current to reach the distributor. When the key is in the normal 'run' position, the current flows through the ballast resistor or ballast wire. When the key is in the 'start' position, the current flows through a separate non-resistor wire from the starter motor. If the circuitry for the normal 'run' position is faulty- perhaps a falied ballast resistor, then the ignition will work on in the start position.

I know little about later C3 ignition, but since the OP has run a direct 12V to the distributor, it sorts of points away from the switch as being the cause.

 

[GTR1999]

Shot in the dark here, but if it's cranking and not firing maybe there is a "kill" switch installed in the circuit?

 

[GerryLP]

Pre-HEI cars have two separate paths to allow the electric current to reach the distributor. When the key is in the normal 'run' position, the current flows through the ballast resistor or ballast wire. When the key is in the 'start' position, the current flows through a separate non-resistor wire from the starter motor. If the circuitry for the normal 'run' position is faulty- perhaps a falied ballast resistor, then the ignition will work on in the start position.

I know little about later C3 ignition, but since the OP has run a direct 12V to the distributor, it sorts of points away from the switch as being the cause.

Ok Mikey. I'll bite, but I believe we are talking about an HEI, 1981 Corvette, right?

And besides, what purpose would it serve an ignition that one would be required to hold in the run position? It may be some curious functionality, that perhaps innadecuate design is allowing, but heck, I can make my washer machine by pass the fill level settings, and that does not mean that it was an intended outcome.

It is puzzling indeed this little problem, or perhaps I am not reading well in between the lines, but something is amiss (no pun intended). What would it be your best guess? There is probably not enough detail to provide a course of action to our dear fellow member.

Goodness! Could it be a coil, starting harness, timing related, or what??? Does anybody have the next suggestion for our fellow brotha?

 

[Vettehead Mikey]

As I said, I know little about later C3s, but since the OP has bypassed the switch and it's wiring, I'm kinda stumped too.

 

[6880 Mike]

Read the computer and see if you have a list of error codes.

 

[68vet427]

Could any little critters have chewed any wires while it was stored?
Joe

 

[GerryLP]

gman,

Perhaps it would help if you posted some images of your distributor and starter including wires, to see anything catches our eyes.

Spell out conditions; for example, engine cranks, lights off, does it stumble does it sound as if it was just pushing air....or perhaps, load a video up in Vettetube.com or YouTube.com so that our experienced membership can help you troubleshoot.

If you do the video, remove the air cleaner's lid, so that we can see what it does while cranking.