92 454 ignition cuts out

I just purchased a 1992 3500 dually 2wd with a 454. On the road trip home with it ( 140 miles ) the ignition would cut out for a second, but would keep running. It seemed to do it more when I was putting a load on the engine ( going up hills ). I asked the previous owner and he said he only ran premium fuel in it, and I put regular in it on my way home. Would the lower octane fuel cause this problem? When the engine would cut out, the tach would drop to zero, and would come right back to life. It almost felt like someone turned the key off. No other gauges or electrical items were effected. Not sure if it's fuel or ignition problem, any help would be appreciated.

If you have not already done so check your battery cables and battery terminal ends for loose or corrossion. Battery cable ends were corroded on my 96 causing it to stall and start right back up.

Good Luck

Sounds like you might need to replace the ignition coil.

OK, so my local mechanic checked it out and said the ECU was loosing communication with the engine. He put a reman. ECU in it, and same thing. He said it's operating in "limp mode". Any thoughts as to what I should try before I take it to a Chevy dealer?