Rough Idle in gear 1994 Celica ST (automatic) Options

[Noahwhite2014]

So i have purchased a 1994 Toyota Celica ST Hatchback (Automatic) from a friend a week ago, but he's not available now since he moved to another country (which is why he sold it to me). Ive always been into Celica's but never owned one.

Now that i have it, I'm having an issue with a low idle while in anything except park or neutral. Also, this problem does not happen once i start the car. When i start the car, it will run fine and idle at about or a bit under 1K RPM whether in park, reverse, neutral, drive etc... But once i start driving and bring the RPM above 2k, when i stop and idle again, the RPM drop to around 400-600 (sometimes even lower) and the car shakes when its around this rpm and then smooths out when the RPM gets above 2k

Any idea what the issue with this could be?

I would really love to get this car running well again like when i drove it a year ago or so and it was awesome!

There is a short ram intake on the car. But i don't remember if it was on when i drove it a year ago, i don't know if the intake could cause this problem. It has no brand that i can see, so i can add pictures if you would like.

Thank you all so much in advance!!

[Special_Edy]

The pipe just runs down to an exhaust port in the head, probably best to use throttlebody cleaner and some compressed air, or not clean it out at all. Its tricky getting the nut loose, you obviously need a crescent wrench. You may be able to get it loose if you want without removing the throttlebody or distributor. Remove the distributor and you will need a timing light to reset the ignition advance.
You dont want carb cleaner getting onto your catalytic converter or O2 sensor, and you dont want to knock a bunch of crap loose which will get sucked up into the egr valve and intake manifold.

Carb cleaner will work great in the valve itself though.

[Noahwhite2014]

You dont want carb cleaner getting onto your catalytic converter or O2 sensor, and you dont want to knock a bunch of crap loose which will get sucked up into the egr valve and intake manifold.

Carb cleaner will work great in the valve itself though.

Alright i was kind of thinking it may be dangerous to do this but I'm willing to do anything to help get my car running properly. So the valve is clean and reinstalled now and it idles a bit better (about 30-50rpms higher than before but still low) and it is much smoother now. In gear the RPM also drop about 200... This can't be normal can it? And also when the Air condition is turned on, the car shakes a lot, but not as much as before. The RPM also drops from the AC by about 100.

So:
In gear with the AC on I'm idling around: 200-400
In gear with the AC off I'm idling around: 300-500
In park/Neutral with the AC on I'm idling around: 500-600
In park/Neutral with the AC off I'm idling around: 600-700

I find this odd and so confusing since isn't there a valve that is supposed to bring the RPM up when the AC is on..?

should i try unplugging this valve and seeing if it makes a difference at idle? If yes where can i find the valve/connector to stop it from functioning.

Also just wondering, is it a bad idea to adjust the idle adjust screw just to bring my RPM up a bit? I just want to know as a last resort sort of fix to make sure my engine doesn't die out on me at a stop light on a hot day this summer while my AC is on!