I have an 88 lx 5.0. I am having some idle difficulties and it doesn't appear to directly be the iac. I can let it sit in my drive way and it will sit there and purr just find, usually. But about 80% of the time while im driving down the road, idle will just surge up to between 2000 and 3000 rpm and stay their until I turn the vehicle off. I can stop and turn the car off and back on and idle will return to normal, at least initially. I have stopped when this has happened and left the engine running, gotten out and disconnected the IAC during one of these surging episodes. And the idle goes back to normal. I plug it back in, and the idle goes crazy again. This led me to believe that the IAC was bad, but I have gone through 3 new IAC's, and it makes no difference. Obviously something is sending the IAC incorrect signals. I have ABSOLUTELY no clue as to what it is. If anyone out there can help, I'd really appreciate it. Thanks.