Hesitation when starting

[Stacked360]

The Duster is done with it's 05' hemi and 09' 545RFE nestled between the frame rails, it runs and drives great...but...when I go to start it it cranks for half a second, stops for half a second, cranks again for half second, pauses half second, and then cranks normal and fires right up. I've spoken to Hotwire about the issue and I guess it's the split second when turning the key between run and start that causes the computer to lose power. SO, I've tried putting in a capacitor on the "run" circuit to the computer to try to "buffer" the power between the contacts in the ignition switch. It didn't really do anything.

Has anyone else had this same issue? if so, how have you dealt with it?

Thanks in advance.

 

[Bad Sport]

Can't help with your issue, but that avatar is a hoot!

 

[5.7 hemi]

Do you have 12 volts at the run and start key position?

 

[Uhcoog1]

I had to wire in a relay so I could get a single wire to be hot during crank and run key positions. The megasquirt required that.

At first I wired it like this, as this is how American autowire said to do it.

This didn't work (starter wouldn't stop cranking), because the pink (hot during run) would back feed and keep the relay open. So, I only hooked the purple (hot during crank) up to the switching part, and a 12v from the battery lug on the starter solenoid for the 12v feed. That allowed the pink to be hot during crank and run, which I then used to switch on the relay for the megasquirt.

 

[67Dart273]

I think your cap idea would work.........if you do thus:

You need power both in start and run, so I assume you now longer use an ignition coil ballast?

If not, wire the original ballast brown and blue together, which will give you power in both "start" and "run" but with the short switching time in the switch

Take that point and run a series diode, Radio shack, etc, say, a 5A rated diode, with the banded end towards your ECU, and with your cap on the ECU side of the diode.

the diode will isolate any discharge load from the rest of the ignition run buss, so the only cap discharge path will now be through the ECU

 

[loganscuda]

I had same issue I have my battery in the trunk and added a ground to the frame right off of the battery. I also added a push button start. I use my keyswitch to turn ECM on and button to fire. I put it in the ash tray where the cigarette lighter goes. picked it up at an electric supply shop. So it it easier to push than the ones at the auto stores.