Help! We have changed the spark plug and coil pack in #8. Upper O2 sensor has been replaced in bank 2 (driver side). Sprayed brake cleaner all over and engine didn't idle up at all..so seems like no vacuum leak. Manifold gaskets recently replaced also..

 

What vehicle are you working on?

 

It is a 2004 f150 5.4l 4x4

 

Check out the egr system. I just replace my DPFE sensor. One of the hose nipples was broke and the hoses were rotting out. I had left and right bank lean codes too. I'll know for sure if I fixed the problem when the engine is cold and has to warm up. Here's a good link to test your egr system. http://easyautodiagnostics.com/ford/4.6L-5.4L/how-to-test-the-egr-system-1

 

I have a 2010 Super duty with a 5.4 3V and it has so many codes on it TWO ford dealerships say it is a minimum of $3800 to START to check it out. Cam, phasors chains, or anything else could be the problem i am told. What a nightmare!
My truck has a lot of KM 325K , so it is tired for sure. I am thinking of getting a new rebuilt for it but what if that doesn't fix anything? It starts fine, it runs ok for the first bit, but once running when you pull up to a light after driving it a bit it starts running rough and then dies. Not good. It also has no major ticking on startup but after running a bit there is a noticeable tick for sure.
I wish there was a what to start replacing first list starting with the cheapest to the whole complete engine! What a mess.
Thus the idea of dropping in my 460 now 545ci motor! HAHAHAHHAHAHA

 

Clean your throttle body, they get gummed up and start throwing false lean codes/rich codes making your truck die at stop lights and such, and the best part its free.