FiTech EFI system

Okay,
So here's a little story for you. While my buddy Larry and I were troubleshooting the issue with the Fitech system just letting engine die when letting up off of the gas free revving or driving down the street, I notice smoke coming out of the engine compartment. Panic sets in as the engine stops and everything goes black. I jump out of the car and race to the trunk with the key and a 1/2" wrench to disconnect the battery, I went as fast as I could but the damage was already done. I fried the fusable link I put in for the 8 gauge alternator wire I put in when I put the headlight relays.in (thank God I did that it could have been much worse), the feed wire going from the relay to the starter and the fusable link going into the interior. After the panic subsided we did a little forensics and found that the 8 gauge wire to the alternator had came into contact with the header and melted through causing all of the excitement.

I immediately went to work replacing the fried wiring but while we were doing that Larry said "hey, what's this?" as he picks up what looked like a clear vacuum cap. Turns out it WAS a clear vacuum cap that came off of the throttle body! Watch out for this boys and girls, these caps fit very loosely and I don't know if it was knocked off or if a backfire popped it off but it was definitely off. We replaced it with a real cap and fired the car up (this time without any fire external to the engine LOL). I was sure that this would cure the engine dying problem but not quite. The IAC counts we're waaaaayyyy off and we had to adjust them down from 125. They were running at 10 before but they must have been adjusted with the vacuum cap off. I tried revving the engine again with hopes for better results but no such luck arrrrgh. We then did some research and found this Decel RPM Decay setting. This setting controls how quickly your engine returns to idle. I lowered the value and boom!!!! fixed. See what I pasted from Fitech below. Also, if you are having trouble, like I was when letting up off of the gas while cruising and the engine feeling like it's surging up and down you might want to disable the DFCO (deceleration fuel cutoff). This is used to save fuel but I am more interested in the car running correctly. To disable raise the temperature that it's supposed to come in at from 68° to 300°. I hope that this helps everyone.


Decel RPM Decay = When the throttle is closed, and the engine is returning to idle speeds, the Idle Closed loop will use Target RPM to control the speed during that period. The Target RPM will decay to the normal idle speed in a controlled manner. A smaller “Decel RPM Decay” value will be SLOWER.