I swapped the quadrajet from my old blazer to the "new" suburban and now I´m having some problem getting it to idle ok. The carb ran just fine on the blazer. Now it runs fine with the trans. in park but once you put it in drive or reverse the engine stalls and dies. The engines are both 350's and the only difference is that the suburbans engine has an EGR-valve but it´s not conencted to anything. Could it be a vaccum leak in the modulator on the trans? It's a TH350. Really need some help with this one. I can't go wheeling with it without idle.