I am new to Volvo and am really having trouble figuring out this layout. I have a 940 SE with 98 K on it. My check Engine light is on most, but not all of the time. It runs perfectly. It only gets about 22-23 mpg, is that about correct?

I don't have the owners manual, but I bought a Chilton manual. I found the computer test module. With the wire plugged into #2 I got 1-1-1. In #6 I got 2-4-1 so I guess I have the EZ-116K ignition system. That translates to EGR system flow too low or too high. I am afraid that doesn't tell me much. One friend suggested that it was the oxygen sensor. Any ideas?

If I'm not mistaken, socket #6 is for the EGR system...which would explain why you're getting EGR fault codes out of it. EGR valves crud up over time and can stick open or closed. When they stick open they can cause all kinds of driveability problems, when they stick closed you barely notice it. I'd start by making sure all the vaccuum hoses are intact and then taking the EGR valve off and cleaning it well with Carb Cleaner. If you have a handheld vaccuum pump it will help with diagnosing the problem because you can check the operation of the EGR valve once you get it off.

As for the mileage, 23mpg is about average for a B230FT. They're not terribly fuel efficient engines...which is one of the reasons I dumped mine for the straight six.

Lance