My exhaust manifold is cracked near the bottom and now I have high idle sometimes but now it stalled on me,I hoping was just a fluke.I know the air sensor will make the high idle problem but stalling too? In the mean time can I unhook the air sensor to help.Also on a scale from 1 - 10 how hard is to change ex. manifold.I,m O.K. on working with my older trucks but not with the new injector stuff.Sorry don,t have much time to do a search so if any one knows a thread etc.

 

I just did this myself.

On a scale of 1 - 10, for a novice, I'd say a 8, or the better part of a day. If you end up missing some other tools, like I did with the fuel line disconnect tool, even longer. After doing it once however, I would do things a lot differently, and maybe turn this into a 4 rating, 2 - 3 hour job. Not a 6+ hour job.

If you're putting on a stock design OEM manifold, it comes off the same way it went on. If you're going aftermarket, it can be a hassle.

This was my thread. Read the 2nd and last post.
https://www.cherokeeforum.com/f2/manifold-help-148852/

Here's a decent write-up.
https://www.cherokeeforum.com/f51/je...91-98-a-80445/

I don't think a crack would really make you stall however, or net higher RPMS. If the crack is really big, you could be stalling due to running too rich. Which your o2 sensor would contribute if it's sensing too much air, and not enough fuel. I don't know for sure however.

Maybe you have a few things going on here besides a cracked manifold. Generally they're harmless... They just put a good dent in your MPG if you let them go too long.