Cammed 98z poor idle
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Teching In
Joined: Jun 2025
Posts: 11
Likes: 0
From: Rapid city sd
Cammed 98z poor idle Got a cammed 98 z. Not sure how big the cam is i bought the car the way it is.. its a 98 cammed z28 3 in Borla exhaust cold air intake.. bought it 5 yrs ago and have never had any running issues.. this spring went out and out the battery in it and the idle went to 3 grand and stayed there. I removed the iac and notice some carbon so I replaced it. Now when I start the car the idle jumps from 1000 to 1300 and cycles back and forth. When I get into the throttle it falls on its face then clears out and revea up. Got no check engine lite on. Not sure if sitting all winter could have erased my ecm tune or if Got something else going one. If any ideas would appreciate the info.
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Joined: Jul 2025
Posts: 61
Likes: 7
From: United States
Absolutely sounds like the tune got corrupted from the dead battery. A custom tune for a cam is very sensitive and a power loss can scramble it.
The hunting idle and stumbling are classic symptoms of bad fuel and spark maps. Your new IAC is likely fine. You need to have a shop with a dyno reload the proper tune for your cam; it's not something you can fix with a part.
The hunting idle and stumbling are classic symptoms of bad fuel and spark maps. Your new IAC is likely fine. You need to have a shop with a dyno reload the proper tune for your cam; it's not something you can fix with a part.
