I now have a 87 4runner I just bought for a new project. I noticed it idled high and the check engine light came on every now and then. Checked and found it flashed code 5 then would flash 11 times. I thought 11 would be one flash then a pause followed by one flash. I ignored the 11 flashes and replaced the o2 sensor. It now idles great but while driving it flashes the check engine light 11 times over and over. It is flashing this code the entire time I am driving. What does this switch signal mean anyway. Thanks

 

The earlier ECUs only flashed single codes, so 1 to 13 flashes, vs. the later model ECUs that did 1 and 2 digit codes:
- http://www.4crawler.com/4x4/CheapTri...CheckConnector