Ok I have a 88 t2 with, large streetport, walbro 255, three inch intake and exhaust no emissons. ok now when I get to four grand in boost it spits and sputters and pops hella loud compression is 115 front and back its got new plugs, wires, and cas. And I have been messing with it for about a week now I'm about at my wits end can someone please help me out I'm not getting any help anywhere else any input would be helpful.

 

Secondary injectors not firing up???? Or firing up but clogged??? Could be bad grounds and its causing the 3800 rpm hesitation. Search 3800 on here and you will find more information. It basically requires you check all your ground wires and clean them up, especially the one under the intake manifold.

 

sounds like secondaries not firing~~~

stock ecu? may be in limp mode.

 

^ No limp mode on S4s.

A problem with the secondaries fits, or you're hitting fuel cut. Is there a FCD or aftermarket ECU of any kind, or is it the stock ECU?

 

It is stock ecu and no fcd