HouseCallAuto 6/21/2011You have to rule out a vacuum leak before you start replacing stuff. The TPS can be checked with a simple voltmeter. Just google TPS check. Look for a vacuum leak. The gasket under the throttle body can leak vacuum. The power brake booster can leak vacuum. Any vacuum hose on the engine that carries vacuum can crack / split and leak vacuum. make sure that you do not have a way overdue and forgotten clogged up fuel filter with a gazillion miles on it. That could starve the engine for fuel and cause your erratic idle.