Need help w high idle 92 saturn sl

So my brother in laws Saturn has just started having a strange idling issue the week and he's not able to drive it right now. I don't know much about saturns so if you guys can give me a few ideas on what may be causing the issues I'd appreciate the help.

1. When car is started, there is a high idle from 3k-5k rpm.
2. Upon running for less than 20 sec, there some white smoke from the tail pipe.
3. There also appears to be black sputter coming from the tailpipe.
4. Checked spark plugs: cyl1 is reddish. 2 is also reddish. 3 is black and smells of gas. 4 is same as 3.
5. Checked throttle body and noticed gas pooling in surrounding area in air box.

Not sure what exactly is going on, but my guess would be a faulty IACV and maybe no spark in cylinders 3 and 4.. Any other advice would be great.

the coolant temp sensor and connector is a common problem for them. that would be a good place to start.

Wow ! I just read up on the ECT and it sounds exactly like the problems the car is having. I'll go ahead and replace that as well as the vacuum lines and clean the throttle body and manifold.

Yea, check the vacuum lines for cracks around the connectors, especially on the top of the throttle body (if a DOHC) and at the PCV valve, that usually causes a 3K rpm idle. The spark plug/fuel thing is definitely the ECTS.

Is this a DOHC or SOHC, by the way?

It's a sohc. I won't be able to get to it today. Btw you would you guys happen to have a diagram of the vacuum lines handy?

I should be able to get one at work tomorrow if the Saturn catalog has it. I have never looked for it so I'm not really sure.

Okay so I replaced the ects and the pcv valve but the car is still buzzing like a monster truck. When I get some time, I'm going to try and replace all the vacuum hoses and clean out the throttle body, egr system and intake manifold. Anything else I should be taking a look at?

Btw thanks for the suggestions. Also can you pick up Saturn parts at GM dealers?

Merc wrote: Btw thanks for the suggestions. Also can you pick up Saturn parts at GM dealers?

Yes, any GM dealer can order Saturn parts now.

So I found the culprit. Turns out the pipe that holds the brake booster to the manifold had wiggled it's way out of the manifold. It was kinda disappointing to know something that idiotic would cause a high idle. Not to mention I had taken everything apart before I found the issue. Any how I'm going to replace all the vacuum lines anyways and already cleaned out the EGR valve and TB while it was all apart. Thanks for help