Hi guys, I have a 99TL-P and when I start up the car the RPMs would kick up normaly but when they settle they drop way below 500 and sometimes lower than that other mark close to zero, and then it comes back up to about 500. Result: Not so smooth idle, but not rough unless I have the AC on. I have tried seafoaming it once in the past 2k miles but it didnt help although there was a plume of smoke.

Also, I have a dealer code on my CEL P1457, I replaced the gas cap without much success in eliminating it. I have cleared it thrice and it comes back, stuck on me like a cheap suit! I must say though that I bought the car in Columbus OH so I am not sure if it suffered the salt problem on the EVAP system.

Would the P1457 result in the low idle or the two are not related..? Or maybe I need to take it in for a tune up and adjust the idle, change spark plugs, or replace the stereo (jk)..? Car currently has 172k miles on it.

Any ideas please?!!

 

Could be a dirty/clogged EGR.