Volvo Repair: 1990 740SW 5 second hesitation, 9 times out of 10, airmass

Question
We just had the hose that feeds the idle air intake replaced and now, when you try to accelerate, about a third of the time you get absolutely no change in RPM for up to 5 seconds, then it acts as normal. We have recently had the fuel injectors cleaned and this is not a lack of SUFFICIENT acceleration, but a total lack of acceleration for a few seconds.

Answer
John, If this is the Regina/Rex fuel system then that is pretty much normal.  There are a few tests to run on it but 9 times out of 10, the fuel pump is usually the culprit.  Let me know if its a Regina/Rex.  Best way to tell is if there is a Bosch Airmass meter on it the air filter box then its not a Regina rex.  LEt me know and we can go further with this.  Roger