1992 Ford Explorer bolts and studs

What? Can you explain?

Sorry it exhaust manifold I learning on way lol I got four bolts missing do you know how long RMS last

Are they missing or have they broken off in the cylinder head?

They are missing not broken

That's a good thing!!! As far as the bolts, I don't have anything listed to indicate length, diameter, and pitch of the thread. They are a standard bolt so it shouldn't be hard to find. I looked online for you and found these.

http://www.autohausaz.com/search/product.aspx?partnumber=MM-03411&utm_source=google&utm_medium=nonpaid&utm_campaign=frooglePN&utm_term=03411&crossref=03411&gclid=CM6wuK7elcYCFc6QHwod2IkABg

Based on that listing, 1.25mm is the size and pitch of the thread.

Thanks I got some at O'Reilly Auto Parts 8.99

Sounds good. Let me know if you have other questions.

How hard do I tighten them what to use I'm new at this but learning quick

Also when I start vehicle my rpms go up n down just a little not lot rough idle

Have you ever heard of blue devil rear main sealer

Okay, lets start with the exhaust manifold. They need to be torques using a torque wrench. Most part stores will lend or rent one to you. The bolts get torqued to 18 ft/lbs. Start in the center of the manifold and work your way out going left to right.

As far as the idle, it could be a vacuum leak or a bad idle air control valve (IAC).

Yes, I have heard of the rear main sealer and yes often times they work. Just make sure to follow the manufacturer's directions and don't overfill the engine oil.

Let me know how things go for you.