Exhaust leak 98 2.4l

This is my engine, I need to know what I need to remove in order to get to the exhaust manifold, there is a leak. I may need a sensor also, codes are PO171, PO130, and PO133. Any advice or instruction is helpful, I need to fix this myself if at all possible, I don't have a lot of funds.

 

Can anyone help?

 

I suggest a hardcopy repair manual or https://www.tacomaworld.com/threads/2001-2004-tacoma-factory-service-manual.5696/ if you want to rip down into the exhaust manifold. Recapping step by step here is going to be too much and its better you have a hard copy to reference.

For your code issues (and I would start here FIRST),
Check and confirm both of these are within spec. If they aren't, replace them with Denso branded sensors.

 

Thank you these diagrams help a lot, I have a haynes manual but it's hard to follow, I will check out the online factory manual you suggest.

 

I did this job today. Remove airbox cover, unplug maf sendor plug snd on that same bundle of wires are 2 other plugs, remove them. Loosen all the hose clamps from breather to throttle body. Got a little vac line also. Remove plastic cover right behind the air box and there are 3 10mm bolts to remove the steering cable box. Place it on intake. There are bolts holding the square part of air intake to take out. Remove air box hose assembly. Now you can see the manifold. 4 10mm bolts and the heat shield comes off. 6 14 mm bolts hold the manifold on. Just break loose for now. On the cab side of manifold is 2 bolts holding on the egr tube, take them out. I had to loosen the other 2 on the other end of the pipe to-get some room now get vehicle jacked up and using a long extension and a 14 mm deep well take the 3 bolts out of the down pipe and the 2 bolts on catalytic converter. Remove this pipe. Now you can remove the manifold. I had bad problems with the new manifold i bought. It was not flat and the three studs that hold the manifold to down pipe were wrong so i had to purchase new ones. I also spent 2 hours sanding it flat using a granite table and sticky sanding pads. I also had to replace 3 manifold studs as well as all six nuts. Be sure to use pb blaster and give it time to soak before attempting to remove any rusty bolts. You will need 10, 12, 14, and 17mm sockets and endwrenches. When installing the down pipe i had to pull and wedge the exhaust pipe towards the rear of the truck to make room for installation.

 

After sanding

 

Oh and the shiny side of the manifold gasket faces the manifold, not the head. There are YouTube videos showing a step by step process.