she is currently driving a 96 LeSabre, with series 2 NA motor. it does a really wacky thing once in a while. Whenever the car is started, it fires right up fine, then about 1 second after that, it revs itself up to about 2 grand, then stops, and idles fine. it has also done this to her while she'* driving, which has been dangerous, because the car was in gear and almost went out into traffic at a stop sign. although she was able to push the brake hard enough to restrain it, i'd like to know how to stop this from happening. has anyone had this problem? or has anyone else heard of this?

Any check engine light? Codes?
Cars don't rev up unless the TPS is at fault generally. Test it for smooth upward increments or dead spots.
Also possible the IAC needs to be taken out and cleaned.

yes, there'* a CEL, not sure if it was ever read, but maybe i can get it read this weekend.
does that mean like...push on the gas slowly and progressively harder to ensure that it goes up the tach. smoothly?

and what'* the IAC?

idle air control. it'* a sensor on your throttle body.. the roundish one with 2 screws holding it on the front

i got the codes read at autozone last night, and they gave 3 codes. one for faulty MAF/MAP sensor (probably needs a cleaning), one for faulty o2 sensor, and one saying something like "bank 1 too lean", which IIRC can be cleared by cleaning the battery cables. so i guess the MAF sensor was a problem, but i think the whole TB just needs a cleaning

the MAP and MAF are completely different things, which one was it?

I've just recently gotten this same problem. I am going to try to get my codes ASAP, but there is no SES/CEL on.

When I start, it starts just fine, but then begins to idle RPMs around 1500, unless I shift it into gear, because they will stay lower that way... but still higher than normal. If I let it drive in idle, it would top 15mph. It'* insane. It'* particularly bad when I shift from reverse to drive, sometimes in that fraction of a second, the car will top 2000 RPMs and kick when getting into drive. I want to get this problem fixed before it becomes an issue with the transmission as well.

It only seems to do this just after starting the engine. It will stop soon after, and sometimes if I shut the engine down and re-start, it won't do it. Does this sound similar to your girlfriend'* car? I assumed mine was an IAC problem, as I cleaned the MAF sensor when I first got the vehicle.

x2.. map and maf are completely different. And all codes can be cleared by disconnecting the battery cables, but if you are actually running lean, cleaning the battery cables will not help at all

yeah, but i thought that this was a common problem with our PCMs, where it would read a certain error code (P0170, IIRC) and that didn't necessarily mean that it was running lean/rich..maybe i'm confusing this with something else

i brought the printouts of the codes. they were these.

P0102
"The mass air flow input is lower than expected for the current conditions"
P0108
"The MAP sensor or the barometric pressure sensor input is higher than expected"
P0133
"The response time for the O2 sensor 1 in bank 1 was too slow during testing.

i really hope just the MAF sensor is dirty and causing all of this, cuz that'd be the easiest fix