We use this and also the Lubricity formula, it's good stuff but anything from the Flying J will help.
http://www.stanadyne.com/view.php?id=76
Change the fuel filter and report also slap a charge on those batteries and check the terminals for corrosion, ECU's don't like low/irregular voltage.
Bought 2 new 850CCA batteries, new cable ($92.00) Put some 911 treatment in the fuel, and added some oil, and it started, but was back firing, every time I would crank the engine over it would back fire, sounding like it was going to blow up. So I gave it a couple of minutes, then tried again, it backfired and then it ran but very bad, I throttled up to 2500 rpms, and after about 30 seconds, it started running fine. So I figured that my wife sprayed too much starting fluid before starting, and not to mention there was probably still a ton left in there from the day before, so it was probably firing on both intake and exhaust. Runs like new, I am thinking it was a combo of low oil, gelled fuel, and low voltage since one of the batteries was totally dead, and won't hold a charge of any kind. And I don't know why but I put a new back window in it is much warmer now. Now I am not sure of how to remove the fuel filter on the top of the motor.