Volvo Repair: dogging, volvo 740 gl, volvo 740

Question
I have a 1989 Volvo 740 GL with 409,000. miles. It is having a hard time idling. It is fine when cold but when it heats up it chugs and bucks. It stalls as well. I changed the fuel filter and coil but it is still not working. Any ideas where I should look next. The codes say it is injectors. Any help would be appreciated.

Answer
Paula, what are the codes?  Fuel filter is just a myth.  Ive never seen a Volvo Fuel filter clog.  I would be going towards the air mass meter and the ect sensor.  It may be overfueling.  Is your car a LH2.4 car or does it have the Regina Fuel system?  Roger