# Rpm restriction **URL:** \ **Category:** Maintenance/Repairs\ **Created:** [September 11, 2008, 7:29pm UTC](https://community.cartalk.com/t/rpm-restriction/19456 "2008-09-11T19:29:15Z")\ **Posts on this page:** 3\ **Page:** 1
**Author:** ![garytu](https://avatars.discourse-cdn.com/v4/letter/g/5daacb/32.png) [@garytu](https://community.cartalk.com/u/garytu)\ **Post date:** [September 11, 2008, 7:29pm UTC](https://community.cartalk.com/t/rpm-restriction/19456/1 "2008-09-11T19:29:15Z")
I have a 2000 grand prix with a 3.1 engine.When in gear or idling if I rev it up to a little over 4000 rpm the idle will drop back down to under 4000 and then back up to a little over 4000 and repeat the cycle. I have replaced the module, plug wires and plugs. the fuel pressure is around 50 and drops only a pound or two when the idle drops. any ideas? thanks ---
**Author:** ![alex3324](https://avatars.discourse-cdn.com/v4/letter/a/8e8cbc/32.png) [@alex3324](https://community.cartalk.com/u/alex3324)\ **Post date:** [September 12, 2008, 2:09am UTC](https://community.cartalk.com/t/rpm-restriction/19456/2 "2008-09-12T02:09:31Z")
why do you need to rev it up over 4,000? ---
**Author:** ![researcher](https://avatars.discourse-cdn.com/v4/letter/r/edb3f5/32.png) [@researcher](https://community.cartalk.com/u/researcher)\ **Post date:** [September 12, 2008, 5:25pm UTC](https://community.cartalk.com/t/rpm-restriction/19456/3 "2008-09-12T17:25:31Z")
Does it have any driveability problems when you try to take the rpm above 4000 rpm on the road under load? For example what happens when you accelerate up a hill in second gear? Can you get over 4000 rpm?