engine cuts out randomly

[85cobraX]

Hello all.

Been having a very annoying problem as of late. I have an 85 GT with the following modifications:

Holley 650 Double Pumper, Holley Annihilator ignition box, MSD blaster 2 coil, Taylor 409 race core wires, weiand stealth intake, stock heads ported with roller rockers, e303 cam, underdrives, emissions stuff removed - EGR, PCV, Air Pump, canister.

Basically my engine cuts out randomly. Always seems to be when engine is warmed up but does happen at any RPM range. It is like someone has just turned the key off. I still have power though as i can hear my holley blue buzzing in the back and my electric fan going.

I have replaced the ignition switch, rotor, cap, checked all of my connections and see nothing obviously wrong. I am leaning towards a faulty coil? Any suggestions?

Thanks.

 

[kikboxr1]

If your battery cables are old, I would say replace them, and clean the contact points thoroughly. When I re-did my entire engine compartment after a fire, I had a similar problem that plagued me for months. I took it to 3 different shops that couldn't figure it out. Then I looked at my buddy's 5.0 one day and saw he had a smaller wire coming off his negative battery cable that was attached to the firewall.
$.10 later, my problem was solved. I doubt that is your exact problem since the grounding to the firewall was mostly for the computer's benefit as I understand it, but nonetheless I would check all your cables and ground points.

 

[dude5l]

I would look at the coil or the Holley ignition box. Try by-passing the box and see if that fixes it. I tried a Holley Annihilator box once and didn't have any luck with it at all.