This is from another post on the board and it might be the answer that you are looking for. Sometimes the fuel pressure can really throw things off as far as starting and idle go. Another possible problem is dirty injectors. Hope this helps and welcome to the site. Dan
QUOTE: Hey Maverick, First sorry it took so long to get back to ya, had a problem with getting the reeds in the first place, then I had to do some testing so I could both help myself and you out. Ok here goes...I first got the reeds and put them in, same story as you...idled low and just didn't seem right, I check this and that, that and this, nothing made sence. So I was figuring the only adjustability that you could possibly have on an EFI sled is fuel pressure, not to mention I've heard that the fuel pressure regulators on these sleds were doggy poop because they set them at factory to be extremely high and you can't adjust them. So I ventured to buy a fuel pressure regulator with a guage and put that on.....well let me tell ya...HOLY CRAP!! the sled now runs 2000 times better than it has since I bought it, I have a perma-grin, she moves now like she never did before!!!!! It's just unbelieveable at how much of a difference it makes, it starts on the 2nd pull every time, it's wicked snappy now and just wants to rip!!! Ok enough of that, I'm currently running 38 psi. but I've heard 36.2 is the optimum for the most sack, I just don't want to push it until I'm comfortable...You have to get one!!! It WILL!! solve you problems!!! I did a little test and pushed the fuel pressure up to about 43 psi and the sled dogged down to about 750 rpm at idle and was acting strange just like it was before I got the regulator so it pretty much seems cut and dry to me.....
Well, I hope this helps, and I do highly recomend everyone with an EFI should get a fuel pressure regulator because with the simple turn of an allen wrench you can adjust your......"jetting".....and add any mods to your sled..... : Quote