6000 2.5 Strange idle

1988 Pontiac 6000 2.5L Garnet Red - hardly any rust. On Friday, the car started idling strange. This is a little tough to explain, let alone understand, but I'll try my best. I drove home Friday from school. When I got to the driveway at our house, I noticed my braking wasn't as good (although not abysmal). I then backed up once I was stopped. I noticed the idle was higher than usual and not even pushing on the gas, the car started backing itself up at a good rate. (Normally I would have to push the gas a little from where it was.) Then, when I parked it, the RPM went pretty high. I don't have a tach to tell.

-Today- Started the car and all was normal. When I put the car in reverse the RPM jumped for a millisecond as usual, except the RPM jumped higher this time than it has in the past. I drove to school and all was normal. When I put the car in park at the parking lot, the idle actually went down instead of up. Then, on my way home, I didn't even need to press the gas pedal going 35MPH on a flat surface, which I normally do at least a little. Then, going home, there's a steep hill that I always hit around 40MPH. I don't push the brakes down the hill and just let it roll down the hill. Normally when going down the hill, I'll reach around 43MPH or 44MPH. Today going down that same hill and hitting it at the same speed, I was pushing 46 or 47MPH. No extra wind to help push me down the hill as it is coming from the east, which would be blowing against me. Also, when I was coming to a stop, I could hear the engine and feel it down-shifting from 3rd to 2nd and 2nd to 1st. I don't normally notice it quite so much, although the engine is noisy. Again, the same thing when I got to the driveway. The idle was lower in park than it was in drive. Mother said that she thought it idled strange today also when she heard it from inside.

It doesn't make sense to me, but maybe it will to you. Have any ideas? Should I check my transmission/transmission fluid again? The car has

124,100 miles and it does have a very small transmission fluid leak (a few drips) that I'm considering getting it checked out and possibly fixed. (Go ahead and tell me that I need to have it fixed now rather than in a few months.) We haven't messed with the timing or anything, actually, we haven't done much to it since the oxygen sensor back in September or October. Thanks.
Reply to
Travis King
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TPS

Reply to
=?x-user-defined?Q?=AB?= Paul

i agree a bad tps sensor will cause that.

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Reply to
ds549

With a bad TPS u will not get power and the engine will be running eradically. The ECM will think the throttle isnt moving, therefore will not give it more gas, acting like the throttle is still closed. The idle air control motor (or valve on some cars) is supposed to regulate the idle, increasing and decreasing idle as needed. This is usually located on the air intake. We have recently been having problems also and replaced this component. no help for us, hopefully for you. cost around 35.00.

Reply to
ladylorac

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