Hey peoples.
I drove my R from 7500 feet altitude to about 2500 today. Flagstaff to Pheonix. When I arrived to the auto-X my car was dieing at idle. It would drop to about 500RPM, and die.

I just replaced all of this about 3000 miles ago:
plugs
wires
fuel filter

The CEL was blinking so I went to Checker, obd-II reader said misfire in all 4 cylinders.

What do you think is wrong. I really need some help with this one.

Car has 63000 miles
VAFC-II w/JDM ecu, dyno tuned @ dyno-comp.
JDM header
Kakimoto exhaust.

 

anybody have some advice for ian?

 

5000 ft elevation change is very significant. At lower altitudes the air is much denser, thus contains more oxygen molecules. Your car is most likely leaning out to the point that it can't keep itself running anymore. Did you tune the car at 7500ft? I think that would be your problem right there. A wideband would be a nice addition to your setup. So when you go to lower elevations you can just enrich the entire fuel maps with the vafc and then put them back where they were when you return to Flagstaff.

 

try to disconnect the battery

 

i think, though, if you reset the ECU w/ a fuel tuner, like SFC, the computer will begin its learning curve with your SFC settings and it will be like the SFC wasn't there. i think you have to switch the SFC to 0 change across the board, let it learn, then go to your "tuned" fuel map. somebody please enlighten me on this, as i am sometimes baffled by the intelligence of my OBD-I computer.