88gtman

My Ls1 is acting weird on startup. When I first start it the engine will almost die then the idle will pickup and fluctuate for a moment befor finally settling down. Once it has settled the car runs fine. This only happens after cranking. I think it may be the IAC, but it is $100 for a new one so I want to get some more opinions first. No engine codes are present.

xhifer

Could it be a vacuum leak

71novaguy

iTrader: (2)

you can test the IAC. remove it, spin it out to full extention, and put it back in but leave the electrical connector unplugged. it shouldnt start without you giving it some gas. pull it back out, screw it in a few turns, and it should fire up, but idle at whatever rpm you screwed in to. that should show you if its the iac

myk

iTrader: (4)

Could be the IAC, so clean it before anything else. Then, follow 71's post-that's really good info btw...

71novaguy

iTrader: (2)

cant take the credit for it. intimidatorss gave me similar advice on my car. I thought my scan tool would pin point it, but nothing beats advice of someone whos been there.

99VetteFRC

Take the throttle body off and clean with carb clean. Remove the IAC first and clean the pluncer seat in the valve body. DO NOT spray the IAC directly, wet a rag with carb clean and wipe the plunger clean. Most people don't believe this works but I work at a dealership as a mechanic and it make a huge differance.