Are there any guys out there who are all over the Buick 3800? I have one in my personal van, a '95 Pontiac Trans Sport. The MAF signal dips into zero volts when cruising (5% throttle open). The van bucks and heaves bad. When I step on it, or let off , it clears up. I've replaced the sensor and the PCM, along with many other things, all to no avail. Any thoughts? Suggestions?