Well, I was thinking about you as I was working on my car today. It's been off the road for 3 months now and it sure shows!
Look at how dusty she is! And how rusty the rotors are!
It started right up after I finished but it has some kind of code and it's running with no boost like your car does when you cold start it. It looks like if there's a code, it'll only run so hard...
The first place I went was the car wash...
One other thing occured to me. Have you ever replaced or serviced the K40 relay? I think it supplies power to all the sensors but I'll have to double check the wiring to be sure. If it's sending jittery or intermittant power, it's sure to cause trouble...