camaroeater

At start up in the morning it idles at 1200 then settles at 700rpms, but sometimes(never on 1st start up of day) it will instantly drop to 600rpms for a sec, then goes up to 700rpms. I noticed as I turn igniton that the rpm needle only goes to 1000rpms as it revs up. On a good start up the needle will rev up to 1300rpms as I turn ignition. Is this a fuel pressure problem? Bad fuel pump?

PRO50SC

Have you ever cleaned the t/b or the IAC motor? If not, I would start there.

camaroeater

Yep...did that. This started after I installed headers and O/R h pipe a 2 weeks ago. The idle was dropping from 700 to 600, then instantly back to 700 after sitting at stoplight for 1 min.+. Then after a couple days it would go down and up form 600 to 700 for a minute or so. Last night...I loosened and retightened theH pipe andit fixed the idle problem(connection was off at where h pipe connects to header on driver side). Now I want to fix the low rpms drop upon start up.