Hi Scotty my 1989 chevy c1500 with 5.7 tbi Ran great until I rebuilt tbi, ever since rebuild it has surged up and down at idle and throws a code 44, runs great when you're driving. All new sensors, and a total rebuild kit for tbi, no vaccum leaks,good timing, new distributor,new fuel pump,new fuel filter,good ecm. Its a dang mystery, i have had 4 mechanics look at it and they have no clue what it could be.
Well let me tell you that's throttle body injection is kind of an old system that you can't get that much analytics on when you're working on them. And you have all this problem after you rebuild it. Now I don't know what kind of injectors you're used gaskets whatever, but it's imperative that all the injectors are new one exactly the same. For instance, if you got rebuilt ones they could be garbage. And of course you have to use on the gaskets and seals and o-rings on everything or you'll get leaks and then it'll run like crap
Thanks scotty I'm going to look into it