Volvo: 1990 240 DL 2.4 fuel injection issues, haynes repair manual, vacuum hoses

Question
Hey Ray,

I just picked up a 90 240DL wagon. It had been starting rough cold and hot, so I ran some injector cleaner through it with a full tank.  Gas mileage improved after that 1st tank with the cleaner additive. Refuelled the next tank without the FI cleaner, 50 miles later the check engine light came on and my mileage dropped from 25 to 16 mpg.  I stopped and checked the computer under the hood on #2 the fuel side.  The code came up 2-3-2, compensating for rich/lean fuel (though this code apparently shouldn't set off the check engine light according to Haynes Repair Manual).  I thought that the cleaner may have effected the fuel injectors (clogging them more with loose debris) or the O2 sensor was effected from this cleaner additive.  So I ran a third tank of fuel (93) with more cleaner(2nd time) hoping it wasn't effecting the O2 sensor.  After this tank I reset the computer, thinking that if this 2nd tank of cleaner flushed out the injectors, the computer would remain at 1-1-1, and no check engine light come on.  So I ran the car with a fresh tank of 93 with no additive for about 150 and then the light came on again.  This time the only code on the computer is 1-1-3, fault in fuel injectors.  My MPG is horrible.  Though it starts a bit better both hot and cold, and idles fine.  There is a slight high idle immediately after the engine fires, lasting for about 2-3 seconds, then a smooth steady idle.  I don't have a voltmeter as I'm on the road, so I can't check the O2 sensor.Do you think it sounds like an injector or the O2 Sensor or somethig else? Thanks!

Answer
West,
I have had quite a few cars that have had those codes and the fix was the air mass meter. Even though I have tested plenty of air mass meters voltage and ohms with perfect readings, the fix was also a air mass meter. You have made sure that all vacuum hoses are good and not leaking, right?
Another thing would be to see what the fuel pressure is like. If it is too high or low that would also set fuel trim and injector codes.