Rough idle on warm start up (20 minutes), 87 7MGTE

[Bru]

After my last posting, the problem with not starting when hot came back. It was like the timing was off the way it cranked. All I had to do was wiggle the wiring at the cam position sensor housing and it would start. Then it got worse by shutting down on the road while driving. Not good. I was also getting a code 14 for the Igniter but since wiring connects them I figured that the problem was in the wiring. This is what fixed it. There is a bundle of 3 ground wires that are crimped to a 4th wire that goes to the cam position sensor plug under the tape wrapping between the plug and the CPS housing. I unwrapped the wiring and cut the copper crimp open with a small pair of nippers. I guess a dremmel wheel would work also (wear safety glasses). I released the grip of the crimp by using a second pair of mini pliers. The wires looked a bit oxidized so I scraped them clean with a razor blade. They appear to be silver. I used radio shack lead free solder (tin/silver) and some flux to solder the 3 ground wires together and to the wire that goes to the plug. I wrapped and insulated the ground bundle before wrapping up the bundle against the other 3 positive wires insulation as it was before. After 2 weeks I have had no issues. Fuel mileage has actually increased by about 1 mpg or 5% to 20.2 mpg. This must be another Supra Achilles heel that takes years to appear.

Update:05-10-12 The problems came back. I got a got a cam position sensor that was only a few years in use. see my posting below.