Idles like complete crap

[906000pos]

Okay, I just bought a 1990 pontiac 6000 LE for $850.00. When I got the car it had two codes in the computer, 34 for map and 13 for o2 circuit. I replaced the map and o2 sensors. The code for the map went away and the o2 code did not. I then bought a new computer and this solved the code 13. Now the car still idles like s@#t. On start up, it will run very rough almost like it has a misfire for 15-30 second, and the gets better.While it is idling bad, it seems to straighten out @1600 rpm or so, anything less still causes it to run horrible. When driving the car, it runs fine until you stop, then it surges two or three times before the idle levels of. I have checked the throttle position sensor and the IAC. Both test fine with a VOM. The car was also just tuned up. New plugs, wires, and coils.

Somebody Please help!!!!

[GTP Dad]

Have you cleaned the throttle body and the idle control motor. This should help to solve your idle problems. Also check the vacuum lines and the pcv valve.

[Jim Adams]

I would have to agree with GTP dad it sounds like you have some tarnish on the back of the throttle plate and it needs to be cleaned off or it is sucking air someplace.