Stops At 3000 RPMs (1991 TA)

My 1991 Trans Am has been running fine, my husband and I just restored it.

We got the oil changed in it yesterday, and I noted that they only put 4 quarts of oil in it.
We have the 5.0 TPI that calls for 5 quarts, when I told the service writer he said that they pulled up the car and thats what it called for. But I know that they pulled up the 3.1 V6 Firebird, and not our Trans Am.
We drove it not 5 miles when it started acting up. When my husband trie to open it up it won't go over 3000 RPMs when in drive. But if it's in nuetral it'll practically red-line.
Could it have been the 1 quart short of oil?
We are going back to get it added in, ut could it have messed up the car?
HELP

When the car is warmed up good (drive it for 5-10 miles) look up under it at the catalytic converter (best if it is dark or near dark) and see if it is glowing. If it is the cat is plugged and needs to be replaced.
There is no way being 1 qt low on oil is going to adversely affect your engine, especially in just a few short miles.

Next time tell the morons that you don't care WHAT their computer says, put another qt of oil in it, period. Or better yet, do it yourself.
Their computers are only as good as the moron that put the information in it...GIGO.

Even if they do short you on oil.. Don't they have to show you the dipstick and that it's at the right level (i know they can cheat that but still)?

When the car is warmed up good (drive it for 5-10 miles) look up under it at the catalytic converter (best if it is dark or near dark) and see if it is glowing. If it is the cat is plugged and needs to be replaced.
There is no way being 1 qt low on oil is going to adversely affect your engine, especially in just a few short miles.

Next time tell the morons that you don't care WHAT their computer says, put another qt of oil in it, period. Or better yet, do it yourself.
Their computers are only as good as the moron that put the information in it...GIGO.


THANKS! I took it back there adn had them add the extra quart. But funny you mentioned the cat, cause just Friday (the day before this happened) we had a new one put on. Could they have messed it up?
Also, I was wondering if it could be the throttle position sensor... It seems like when you're driving it and press down on the gas pedal, then it won't go over 3000 RPMs, which now btw won't go over 1500 RPMs, but if you manually rev it up from under the hood, it will. Or is that just because it's in nuetral? Cause earlier it wouldn't do it even if in nuetral. So confused...

If it revs freely in neutral but not under a load (driving), that is a calaaic symptom of a plugged cat.
Have you tried using the gas pedal while in park/neutral to see if it revs past 3k?
If not, try it. If it won't rev past 3k with the pedal...check for something up behind the gas pedal keeping it from going all the way down...like the floor mat or some other object.
If that checks good, watch the throttle blades while someone floors the pedal (engine not running) and see if they open all the way. If not check for binding in the throttle cable.