"...I have been chasing a P1275 CEL code that I started getting when I put on 100-cell cats and had the car chipped. I also replaced all 4 oxygen sensors at that time. We have been playing with moving sensors and we even replaced one of the cats that the code reader said was running at a low efficiency. Like clockwork at 120-125 miles after we mess with the system I get the P1275 CEL again...
That made us think it was the cat on that side, which we replaced last week, I just put on 125 miles, and again got the P1275 CEL,..."
"Hi Ed,
Just wondering about your code. Any new updates??? Let us know what you've come up with."
I have had the car in the shop for a week for them to play around with chasing the 1275 code. They found a number of interesting things. First, a possible small air leak on the intake after the mass air flow sensor (vacuum leaks of that sort have sometimes triggered 1275 codes). Small leak, but they fixed it.
They found one of the front oxygen sensors running a little low in efficiency (they replaced both front sensors), finally, they found that one of the 100-cell cats was running at slightly below normal efficiency (they replaced that Cat), yikes.
Its a 200+ drive home from the shop tomorrow, if its going to throw a code, it will do it on the way home, and I will be one unhappy camper. BTW, if the car is behaving itself on the way home tomorrow I think I will do a dyno run, as I have the dyno data from before these repairs.
Ed