The vehicle has 160,000 miles and had been running great. I pulled into traffic, put the petal to the floor, and it started stumbling and shaking. I pulled into the parking lot where I was going and expected it to die but it maintained idle but shaking real good. When I started it back up the SES light came on. I was able to coax it home but there was no acceleration, wouldn't go over 40 mph, and was still shaking bad. I used my code reader and got the code P0340, camshaft position sensor. I replaced the sensor but it is still doing the same thing and still showing the code. It will start if I push the gas while cranking but it won't rev over 2K. I am thinking it jumped timing but most of the threads I read say they have never seen this on these engines. I want to get some opinions before I start removing the timing chain cover.

 

My 99 5.4 threw a fit similar to this and it was the fuel pump. Wouldn't take over 1500 rpms and would fluctuate constantly. It wouldn't idle and would just run like junk. It would do it intermittently and would be okay one day to the next so I'm not sure if that's your problem, but could be something to check. I never got that code from it. I would get out and smack my fuel tank towards the front and it would start and run okay for a while then start having issues again.

Might not be your problem but it's something to consider.

 

The cam position sensor triggers a signal to the computer when the gear segment passes by it.
This controls fuel injection timing per each cylinder.
You need to check for this signal before taking things apart if it is only a harness issue.
The computer is missing the signal or it is out of time frame expected. (error)
If this started with the motor already running, I would doubt it's a slipped chain.
Everything is already in motion but stranger things have happened.
If the chain tensioners are worn, and chains stretched from wear, it could be possible.
Another way would be to check #1 cylinder for the valves being closed at piston top dead center on the compression stroke. If either one is just closing or opening at that point , it's cam timing.
Good luck.

 

Thanks, I'll check the signal first. This started when I came out of a u-turn lane and floored the accelerator so if there was wear on the chain or gear I'm thinking it could have jumped a tooth.