Boost Trouble
 

I recently replaced the head gasket on my 1990 Turbo Coupe and took it out for a test spin today. It runs and idles smooth, but when the turbo spools up towards 4 psi it feels as though it looses massive amounts of power and it pulses very rapidly almost like it is missing. I set the time so I know that couldn't be a factor. The car ran fine before the head gasket blew and was boosting a solid 8 to 10 psi. Any ideas on what I may need to check or what could possibly be causing this problem?

Any information would be greatly appreciated as I am stumped!

knock sensors? are they pluged in?/broke?

afm wireing?

buddy of myn has the same problem

do a code chech should tell you

if its your knock sensors then it would cause the issue your explaining as they change the timing
hope this helps

Missing under boost? After you've checked for codes, check your coil ground and double check intercooler piping, clamps and hoses.

+1. i concure doctor