'89 Suburban 4.5L Engine Code 33

Hi,

I am getting an engine Code "33" on my '89 Suburban. Book says that the MAP Sensoe detected an unusually high voltage....... What's this about? Is this a DIY job or should I take it in?? Is this going to cost a lot??

Thanks,

swb1

What is a 4.5 89 Sub, no such engine, anyway check for proper vacuum to map sensor first.

Sorry for the confusion :-( the engine is a 7.4L

swb1