# Replaced lower and upper intake and throttle body gaskets and cleaned a couple other things and now idle is high and fluctuating **URL:** \ **Category:** Maintenance/Repairs\ **Tags:** lesabre, buick\ **Created:** [August 2, 2020, 5:09pm UTC](https://community.cartalk.com/t/replaced-lower-and-upper-intake-and-throttle-body-gaskets-and-cleaned-a-couple-other-things-and-now-idle-is-high-and-fluctuating/168183 "2020-08-02T17:09:23Z")\ **Posts on this page:** 8\ **Page:** 1
**Author:** ![Seth19man](https://avatars.discourse-cdn.com/v4/letter/s/c4cdca/32.png) [@Seth19man](https://community.cartalk.com/u/Seth19man)\ **Post date:** [August 2, 2020, 5:09pm UTC](https://community.cartalk.com/t/replaced-lower-and-upper-intake-and-throttle-body-gaskets-and-cleaned-a-couple-other-things-and-now-idle-is-high-and-fluctuating/168183/1 "2020-08-02T17:09:24Z")
I had to replace my lower intake manifold gasket so I ended up replacing the upper one and throttle body gasket as well. I ended up cleaning throttle body, MAF sensor (with proper cleaner), and fuel injectors. Car runs fine but the idle was fluctuating between 2,000 and 2,500 so I’m a little concerned. I was thinking this might be normal because I did clean the things I did so the car might have to reprogram itself to run differently since everything is cleaner now. CEL is on but pretty sure that’s just because I unplugged all the things that I did. ---
**Author:** ![db4690](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/db4690/32/2583_2.png) [@db4690](https://community.cartalk.com/u/db4690)\ **Post date:** [August 2, 2020, 5:17pm UTC](https://community.cartalk.com/t/replaced-lower-and-upper-intake-and-throttle-body-gaskets-and-cleaned-a-couple-other-things-and-now-idle-is-high-and-fluctuating/168183/2 "2020-08-02T17:17:38Z")
Did you plug everything back in . . . ? Electrical connectors, vacuum hose, and so forth . . . ? Do you hear any obvious hissing sound(s) when the engine is idling? And just what year is this LeSabre? What engine? ---
**Author:** ![Seth19man](https://avatars.discourse-cdn.com/v4/letter/s/c4cdca/32.png) [@Seth19man](https://community.cartalk.com/u/Seth19man)\ **Post date:** [August 2, 2020, 5:27pm UTC](https://community.cartalk.com/t/replaced-lower-and-upper-intake-and-throttle-body-gaskets-and-cleaned-a-couple-other-things-and-now-idle-is-high-and-fluctuating/168183/3 "2020-08-02T17:27:02Z")
2003 Buick Lesabre 3800 series 2. Everything is plugged in and no hissing. A little bit of smoke but pretty sure that’s from spilling coolant on my exhaust manifold ---
**Author:** ![Seth19man](https://avatars.discourse-cdn.com/v4/letter/s/c4cdca/32.png) [@Seth19man](https://community.cartalk.com/u/Seth19man)\ **Post date:** [August 2, 2020, 8:08pm UTC](https://community.cartalk.com/t/replaced-lower-and-upper-intake-and-throttle-body-gaskets-and-cleaned-a-couple-other-things-and-now-idle-is-high-and-fluctuating/168183/4 "2020-08-02T20:08:17Z")
Update: Car idle is 1,000 when AC is engaged and jumps to 1,500 when it’s disengaged while idling. Another problem that is now happening is when I step on it and I’m moving fast at speed, my car rpms only hit 2,500, even when I’m all the way pedal to the metal. I did accidentally take out my throttle position sensor when I mistakened it for my MAF. I have a trip coming up and it’s important that I figure this out. ---
**Author:** ![bing](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/bing/32/4619_2.png) [@bing](https://community.cartalk.com/u/bing)\ **Post date:** [August 2, 2020, 9:17pm UTC](https://community.cartalk.com/t/replaced-lower-and-upper-intake-and-throttle-body-gaskets-and-cleaned-a-couple-other-things-and-now-idle-is-high-and-fluctuating/168183/5 "2020-08-02T21:17:08Z")
I think you may need to readjust the idle air control solenoid. If I remember correctly anytime you mess with it, it needs to be readjusted but it’s been so long I don’t remember how. Just look in the book. ---
**Author:** ![Bugmenot](https://avatars.discourse-cdn.com/v4/letter/b/7c8e57/32.png) [@Bugmenot](https://community.cartalk.com/u/Bugmenot)\ **Post date:** [August 2, 2020, 9:26pm UTC](https://community.cartalk.com/t/replaced-lower-and-upper-intake-and-throttle-body-gaskets-and-cleaned-a-couple-other-things-and-now-idle-is-high-and-fluctuating/168183/6 "2020-08-02T21:26:18Z")
The PCM is supposed to reset/calibrate the IAC valve with just one key on/off cycle. Try cycling the key without starting the engine, if that hasn’t already been done. ---
**Author:** ![Seth19man](https://avatars.discourse-cdn.com/v4/letter/s/c4cdca/32.png) [@Seth19man](https://community.cartalk.com/u/Seth19man)\ **Post date:** [August 2, 2020, 9:34pm UTC](https://community.cartalk.com/t/replaced-lower-and-upper-intake-and-throttle-body-gaskets-and-cleaned-a-couple-other-things-and-now-idle-is-high-and-fluctuating/168183/7 "2020-08-02T21:34:21Z")
Update: Just hooked up my TP sensor wrong. Thank god it was nothing more, I was worried! ---
**Author:** ![bing](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/bing/32/4619_2.png) [@bing](https://community.cartalk.com/u/bing)\ **Post date:** [August 2, 2020, 9:42pm UTC](https://community.cartalk.com/t/replaced-lower-and-upper-intake-and-throttle-body-gaskets-and-cleaned-a-couple-other-things-and-now-idle-is-high-and-fluctuating/168183/8 "2020-08-02T21:42:59Z")
Another happy ending.