idle issues again

[3pt1lumina]

ok now the car idles at about 3,000rpms (no tach i'm doing this by ear) when the engine is cold. when it hits operating temperature it goes downto normal. before i had issues with a "stumbly" idle and that was the lower intake manifold gasket. now i have this high idle issue??

 

 

on my 90 lumina (3.1) it was the IAC... could that be this too?car has new plugs/wires

 

 

btw, it's a 97 lumina with a 3100...112k... help please!!

[Canada]

Its quite possible you have a sticking IAC motor......but its also possible you have an intake leak somewhere.

 

Spray some carb clean around the intake passages when the idle is high.....see if the rpm changes. Typically, there is a crack someplace and its leaking air into the engine.....when it gets warm, it seals back up.

[3pt1lumina]

ok gave what you said a shot, Canada. The car continued to idle normal at one constant speed. Then I took it for a ride and the SES tripped some codes... some codes meaning 5 to be exact lol. here's the breakdown

 

PO120 TPS Malfunction

PO122 TPS Low voltage

PO134 O2 Sensor No activity (bank 1 sensor 1)

PO131 O2 Sensor Low voltage (bank 1 sensor 1)

PO137 02 Sensor Low voltage (bank 1 sensor 2)

 

 

after I saw all of this.. i was like ok wtf? ... replaced the TPS because it was cheap and I could return it if it didnt work. So far, so good.. the problem seems to be fixed.

 

So what about the 02 sensors? How do I replace them? They've been done before back about 70k+ or more ago but I didn't do them.

[birdman]

unplug them, unscrew them from the pipe and put new ones in. i belive the o2 sensor is supposed to be replaced every 30000 miles so your due. if there hard to get to rent an o2 sensor socket from autozone or somthing, it'll make it alot easier.