True, but I haven't heard any examples of a DPFI to MPFI conversion that gained MPG, and I've heard more than a few owners say that their mileage suffered.

Mostly I think the issue is that many of the conversions end up using MPFI computers designed for D16 engines on the D15, so their fuel/spark maps aren't quite right.

I haven't done enough checking, but I'm not sure that there's an MPFI D15 except for the HF, and since that was an 8 valve, I doubt the ecu would work on a 16V dx engine. A burned ecu with a custom map might be the only way to improve the fuel economy if I'm correct about all that.

i think you are right but as far as the dpfi to mpfi conversion goes, i have heard the same thing.