P1494 the check engine light stays on an it wont idle down

didnt specify so check these links for assistance p1494 code what exactly is and where is the part located P1494 EVAP Leak Detection Pump Switch or Mechanical Fault Trouble Code P1494

Because the idle of the engine is to low most likely a bad idle air control its a little sensor near the air duck hose on the throttle body itself it hapen that when the battery was disconnct or down good luck and please rate the answer

code p 1494 refers to EVAP system leak detected
p1495 is EVAP solenoid /valve fault when searching for fault codes go to the browser page and type in --- fault code ( what ever code you get -- there are plenty of pages describing the fault and how to fix

one entry for each code

P1294 Injector High Side Open - Bank 2/Target idle not reached
P1494 SPCUT Solenoid Circuit Malfunction
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NEXIQ 125032

as part of the solution i first must ask, is the check engine light on? if not, it may just be time for general maintenance (spark plugs, wires, throttle body cleaning, injector system cleaning). second, while running and running in idle, is the idle varying (continually reving up and down), rough, low or none of the above? answer back and i can help out a little more.

P1494 code is a leak detection pump switch or mechanical fault, leak detection pump switch does not respond to input. The leak detection pump (if equipped) is located under the air filter housing on models through 2001. Check if the vapor and vacuum lines are securely connected to the leak detection pump or a diagonstic trouble code my be set like this. The leak detection pump switch may be bad and need replaced.

Sounds like your IAC (Idle Air Control) valve may not be functioning properly, although not at all related to a battery change.

Are you getting a check engine light? If yes, then take it to any auto-parts store for a free scan to determine any fault.

P1494 means Leak Detection Pump Switch or Mechanical Fault - This code appears when there's an issue with the EVAP System (fuel tank fumes) This can be caused by a improperly secured gas cap, faulty gas cap, crack in the vacuum line, etc.

P1494 Leak detection pump pressure or mechanical fault, hope this helps

i would check the iac valve on all three of your vehicles and on the ones that are sticking and wont idle down i would also verify that the throttle plate in your throttle body is not hanging up on a bur or something.