AleroB888
03-30-2007, 12:37 AM
For the past couple of years, as I kept adding mods to the car, the stock '99 PCM began to have trouble maintaining idle, especially at start-up. I found that I could deal with that by introducing a controlled vacuum leak from just after the SC to the atmosphere. For a long time, I had a tube attached to a fuel filter run out near the fender. When N2Olds got his tuner, it would not read my stock PCM, so we got a spare one and used a stock 2001 (Alero) program. This one gave perfect drivability, with only one glitch. It throws a code (chime, light) because the generator wiring is different on the '99.
When I got my own tuner, I copied my original '99 PCM program to the spare, and where they differed, transferred the engine tables from the '01 to the '99. Some of the tables did not match up exactly in configuration, but I got as close as possible. Still can't get a stable idle unless the minimum target idle is set at 800. Anything I could be overlooking?
When I got my own tuner, I copied my original '99 PCM program to the spare, and where they differed, transferred the engine tables from the '01 to the '99. Some of the tables did not match up exactly in configuration, but I got as close as possible. Still can't get a stable idle unless the minimum target idle is set at 800. Anything I could be overlooking?