Sudden: high idle and high rev. shifts

[TheDirtyBen]

okay, this just started. engine idles between 1200-1500 RPM. also, transmission doesn't shift normally. engine must rev upto around 3000 RPM or i have to completely let off the gas pedal to get it to shift gears. found one vacuum leak and fixed it. no other vac. leaks. IAC is clean.
Both issues started simultaneously tuesday evening. i'm at a loss.

[ProjectMM]

RE: Sudden: high idle and high rev. shifts

what year, make and modle?

[TheDirtyBen]

RE: Sudden: high idle and high rev. shifts

94 olds achieva. 2002 3100 SFI

[imported_germ]

check your throttle posistion sensor and idle air control valve on the throttle body

[TheDirtyBen]

how would either of these affect how the tranny is shifting?

[GPXSS]

The trans shifts via MPH and TPS readings, it runs off a matrix between those two values. I have had my 3100 do some really strange crap when the TPS wiring was faulty, including the trans having a damn fit.

[TheDirtyBen]

ok, went to auto zone. took off the IAC and TPS to be tested. turns out they didn't have a multimeter to test them. so, before i re-installed them, i hosed both down with brake parts cleaner (inside and out).
idle is down to approx. 1100 RPM and trans shifts fine again.

[TheProfessor]

get a vacuume gauge and do a intake manifold vacuume test
you might have a intake gasket leak

[TheDirtyBen]

it's running ok now

[TheProfessor]

what was wrong with it

[TheDirtyBen]

<shrugs> didn't do anything other than what i said above.

[TheProfessor]

must have just been the sensors then