I replaced the exhaust manifold. Put a throttle body spacer, new injectors, cold air intake on my 4.0. Started it up and it runs like crap. Sounds like it's rattling, started smoking, lil water coming out of the tail pipe. When I accelerate it cuts out like its starving then takes off. Anybody have any suggestions on what is goin on with it?
Any help would be appreciated.
Thanks

 

You gave us the engine, but you need to post the year and model.

Are you getting any codes? If so, post 'em.

And get rid of the throttle body spacer. It's not your problem, but it doesn't actually do anything.

 

It is a 1996 Cherokee. Not sure on the codes check engine light is on but has been on.

 

Step one is reading the codes. They will often give you a very good start.

 

Yep. Get the codes read.

I would not be surprised if you installed a vacuum leak along with your "fooled another sucker with this do-nothing gimmick" spacer. When you do the smart thing and take that waste of money out, you can put the TB back correctly and make sure you don't have any vacuum leaks there.

But since you messed with the injectors, it's also possible that you got some o-rings messed up and have some vacuum leaks there.

One way to test for that is to start it up, and spray some throttle body cleaner around each one, one at a time, and see if it affects the engine. Do the same with the TB.

But codes, codes, codes.

 

Step 3 throw away the TB Spacer or use it for a paper weight where it will do you some good. It does sound like a leak in one of the places mentioned above as that is where you worked on.

 

One engine mod at a time. That way if something goes wonky, you've only altered one variable from the "last known good" configuration.

Good luck.