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Replaced lower and upper intake and throttle body gaskets and cleaned a couple other things and now idle is high and fluctuating

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.

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?

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

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.

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.

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.

Update: Just hooked up my TP sensor wrong. Thank god it was nothing more, I was worried!

Another happy ending.