So, as the weather has started to warm up quite a bit, I think I'm starting to notice some ill effects of the current setup I have with a warm air intake. (open element K&N) After standing in traffic, when accelerating, I've felt what seemed like a slight and sudden loss of power, almost like a decent chunk of timing being pulled. It usually occurs with the rpms past 5k, and is more noticeable at part throttle than wide open. Could this be the PCM detecting knock, and pulling timing. I know that hot intake air causes spark knock, and especially under partial throttle, the a/f mixture would be leaner than a WOT pull, and the knock would be most prevalent. The other possiblity I've considered is IMRC fluctuation. I'm defintely getting the secondaries opening like normal, but I suppose its possible that they are fluttering a little if the control box is getting hot and having a hard time holding them open.
When its nice and cool out, the car pulls stronger in the upper rev ranges, and I don't notice this sudden, slight but noticable reduction in power. What I'd like to know is what kind of information those of you that have scanned on these cars have found on the PCMs knock retard tendencies. I know on my Grand Am, a Warm air intake was knock retard city, it would pull a lot of timing out, real fast, with hot intake air. Every degree of timing is supposed to be worth 1-3hp, so if you pull 6-10* of timing out, you'll really feel that. Anybody else dealt with this? I have a good handle on GM PCMs, but I have no idea how sensitive and severely Ford react to knock.
