63 Avanti starting problems

[Coupe Express]

The battery is up and the car turns over well but the car will not start until just as I release the key. If I hold the key in the crank position it will continue to crank but will not start. It's hard to tell but it seems like it finds a sweat spot as I release the key slowly and it fires off. I replaced the ignition switch but that made no difference. The previous owner had replaced the original ignition system with a Mopar electronic system. Any ideas on what I should do next.
Thanks, Mike

[rkapteyn]

Try replacing the starter solenoid.
It has a contact in there that short circuits the resistor while cranking to give the coil full 12 volt while cranking.
It may never have been hooked up with the Mopar conversion.
Dave Thibault 978 897-3158 sold these conversion a long time ago and may have a wiring diagram

Robert Kapteyn

[55s]

This was a common problem in early old Chrysler electronic ignitions. Check the external resistor, was a white ceramic block about 4 inches long x 3/4" x 3/4".

[Coupe Express]

Thanks for the information. I talked to Dave Thibeault and he gave me some additional pointers, so hopefully I'll get it figured out.
Mike

[Xcalibur]

Also, the old ignition switch can do amazingly strange things... and can commence doing so over night! Guess how I know.

[GrumpyOne]

I would suspect the ignition "hot" wire from the selenoid to coil. Also the resistor if the car is so equipped. It's been a long time since I owned an Avanti, (S/N 4500), but remember that the ignition was not electronic.

Like others have stated, the selenoid could also be the culprit.

[unimogjohn]

When I got my Avanti, it would do exactly as you describe. Turned out that the ignition wire to the coil was bad. It would start on the ballast resistor circuit, but then immediately die when the key was released.

[TWChamp]

The battery is up and the car turns over well but the car will not start until just as I release the key. If I hold the key in the crank position it will continue to crank but will not start. It's hard to tell but it seems like it finds a sweat spot as I release the key slowly and it fires off. I replaced the ignition switch but that made no difference. The previous owner had replaced the original ignition system with a Mopar electronic system. Any ideas on what I should do next.
Thanks, Mike

A lot of good answers here for the original points system, but this has been changed to ELECTRONIC ignition.

I'd like to see the schematic for the electronic ignition, but if it has the dual ballast, then I'd guess the low ohm (cranking) winding is open, as mentioned by 55s in reply #3.

[altair]

I don't know the ins and outs of an electronic ignition system but with the old system I had the same problem, just as I came off the starter it would start. I connected a small light to the hot wire on the coil and while cranking it would go out indicating there was no power to the coil when cranking. After checking the system it was determined that the ground from the battery to the block was badly rusted and while cranking, redirected all the power to the rusted contact. Try connecting the ground cable directly on to the starter lug. This cured my problem.

[lschuc]

try a different ignition module that may be mounted somewhere in the engine compartment, or hidden inside the car under the dash. This is the square module that has a black rubber plug attached with 5 or 6 wires going into the plug. Non-OEM modules can often go bad. I recently had the same problem on a '63 Avanti, the problem was the bad ignition control box.

[Xcalibur]

My post applies to EITHER old or electronic system.

[bezhawk]

If it's a Chrysler type of ignition, here's the schematic:

http://studebaker-info.org/tech/Ignition/tbowmopar/ignit1a.jpg

[TWChamp]

Thanks for the schematic. So, the ignition switch sends the full voltage to the coil in the start position, rather than the starter motor solenoid bypass as used on GM cars. I would check the voltage at the + terminal of the coil both in the run and start key positions. It should read 12 volts while cranking the engine.

[altair]

If the ground is not confirmed it still won't send the required voltage.

[rstrasser]

If I read the Chrysler Ignition diagram correctly
I1 is hot in both the start and run position. On a Avanti it is the original wire that went to the positive post on the coil
I2 is hot only in the run position. It is the wire that comes from the 2nd small terminal on the starter solenoid. It is the wire that the service bulletin instructs how to add on the earlier Avantis.
As altair previously said the ECU must be grounded. I don't remember how I grounded the ECU or if it had a ground wire. I have since replaced it with a Malory unit and am thinking about going back to points. Much easier to replace points then fiddle with electronics.
Ron