My '87 4runner does not seem to respond to having the jumper wire in place for setting the ignition timing. The "check engine" light flashes, but the timing does not change at all. I tried a different ECU, but that did not help. Suggestions?

Thanks,
Tim

 

TPS needs adjustment or replacement

 

Right, the IDL terminal is probably not making contact with the E2 when throttle is in idle position. Those are the bottom two terminals. Try adjusting, but if you can't get them to make contact, you'll need a new tps.

http://www.4crawler.com/4x4/CheapTricks/TPS/index.shtml

 

^Its probably the pig tail. The plug that connects to the TPS. My friend's truck has been doing the same thing. We are keeping our eyes on the yards for one.

 

It might not - all the jumper does is ensure the timing is at base. If the parameters are such that base timing is called for, the jumper won't change anything.