Yes, I post here too often. Some problems are related and I have 6 volvo's to take care of. The present problem is in the 1972 and 1973 1800ES's. Poor running and I searched just about everything except the solution. After checking out in the (standard way) the components and wiring I included the Injectors (4 new Bosch), injector grounds, injector connection plugs, water temp sensor, points, plugs, plug wires, coil, fuel pressure regulator, trigger control, relays, and grounds (engine and battery), air temp sensor and the computer I still had a problem of a poor idle and a certain "miss" at speed. Plenty of acceleration but I've owned the car for 20 years and it wasn't running right. I've driven it everyday and logged 2,100 miles since bringing it out for the spring in March. Finally, I took a non standard approach and attacked a fine running 1973 1800ES and butchered the components to discover the problem. Usually I don't want to compromise a good car to fix the bad one because "If it ain't broke..." and ...screw with it and you will break it. The next desperate act was to rip off the injector rack from the 1973 (that included the 4 injectors and a pressure regulator) and put the whole thing on the '72 and see if anything changed. It did! Now the conclusion is that the injectors are the wrong part number and have too weak a spray or they are defective or clogged. I have 2 inline fuel filters on each car and the fuel flow under acceleration is fine. The '73 now has the problems. I have a weber conversion but I'm just about ready to put on a pair of SU's and use the good FI parts as a source of replacement parts for one 1800ES. I have a 544 for the winter with a B20 and have developed a competence with the SU's and prefer them to the weber and am beginning to think the replacement cost of components for the FI is too high to support 2 28 year old cars. Fuel Pump-$300 Injectors--$100 ea Sensors--$??? ea The toasted Wiring harness $350. Why not put a $30 electric fuel pump (low pressure NAPA) and the SU's, cover the injection ports, change the linkage and be done with the FI? I've had 20 years with no problems but perhaps that's all I can expect. The next 20 might be filled with difficult diagnosis and expensive replacement parts! Whew! I feel better now. Yep, those SU's are simple and reliable ( I really like to tinker)and then I'd have all the backup parts I need to support ONE fuel injected 1800es for the next 20 years. Is this a reasonable idea or am I having a bad day and need a nap?

Thanks for letting me vent!

Christopher