EFI, tuning, chipping, read and learn

[Wade Nelson]

Bruce Plecan's Tuning Tips

Yes, the 280Z/ZX has an ANALOG, not a digital fuel injection system.

This is a great article on tuning / re-mapping DIGITAL fuel injection systems. The article is based/ oriented towards GM (General Motors) EFI.

If you hope to understand ALL fuel injection, theory, etc. it makes a great backgrounder. Don't expect to understand all of it on your first pass.

What did I learn re-reading this? That if you lean an engine out too much under "cruise" conditions it may "chug" if the vehicle encounters a slight hill or

stumble upon re-application of the accelerator. In a modern car with digital cruise control, it would be simple enough to detect when the driver presses the

accelerator pedal or if the vehicle speed began to slow down and prevent stumble with a tad of enrichment. That would enable you to program "super-cruise" with added MPG's.

Personally I've never felt modern cars utilize the knock sensor enough to maximize economy. I know on mid '1990's Nissans we saw a lot of knock sensor failures with no significant impact on fuel economy; (Customers strongly resisted the $300 in labor charges to replace a $50 part and their fuel mileage didn't suffer sufficiently to convince them), however my OTHER experience, with my 1991 Four-Runner; it runs noticeably better on premium fuel I have to believe the Toyota EFI is using the knock sensor to aggressively advance the timing.