P0320 code mystery

[tyler.tsb]

I have a 2001 ford expedition xlt 4.6 4x4. I feel like I have done everything I can and nothing fixes it. I have changed the Crank shaft position sensor, the spark plugs, the coil packs and the alternator. It jerks and skips when I hit 2000 rpms.
After I changed my coils it ran good for about 2 months and now it's happening again.

 

[stamp11127]

What brand of coils did you use? The next time it skips, keep the rpms at that point long enough to log a code or codes.
If you have basic engine tools or are able to borrow them, I would get the "vitals" on the engine. One thing to know is the fuel pressure.

 

[tyler.tsb]

I used ENA coils and NGK Plugs. And which tools are you speaking of? I have alot of tools on hand.

 

[Snag]

I would suspect coils again, just one is all it takes to create the problem you are having. Stamp is saying to have a pressure tester to test the fuel pressure as a diagnosis. And you will need a electrical meter to check the coils. Also, need a OBD2 Scanner to help track down the misfires or related problems. I am not that familiar with that brand of coil but the Ford ones are typically life time. They get thrown in the trash when the only problem is that boot going down over the plug.
Good luck

 

[tyler.tsb]

I have a volt meter, and a obd2 reader that can display live data. What's the procedure?

 

[Snag]

I am tech challenged so can't give you the link for the process, but Moose, Bedrck and others are on right now and I bet one of them can get it to you. You have some real good guys on this forum

 

[tyler.tsb]

I also have a code that says I'm running lean in bank one. When it skips it usually divides the rpms in half.

 

[1955moose]

ENA coils are one of the cheaper made in China garbage that's out there 8 for $70.00. Did you ever wonder why Ford charges that price for just 1 coil? Why because they work, and they last. Hopefully you kept some of your old Ford coils. If not you'll need to run a obd test again as Stamp suggested. Hopefully it will leave a code. The other way is to test each coil individually both for ohms, and spark. You'll need a hei spark tester for the spark test. Try running your SUV at the 2000 rpm point with scanner connected. Maybe you'll get lucky and it will give you an electrical code like p0353 or so to narrow down bad coil/boot. You said you changed crank position sensor but still get code. Make sure new sensor and wiring up to sensor is good.


Sent from my iPhone using Tapatalk

 

[stamp11127]

Running lean on just one bank is usually a vacuum leak - lines, manifold gaskets or manifold if plastic.

If your reader can record live data look at the cam position sensor and crank sensor signals when the problem occurs.

Keep the engine at the rpms that the problem occurs and you will get a code eventually. The only real concern is if you have a dead cylinder which is dumping raw gas in the cat. From your symptoms you don't have to worry about that.

 

[tyler.tsb]

The original coils were the originals from 16 years ago and were no good according to tests and were slightly rusted. I will check those signals later tonight and report back. And check the wires.