Check out the thread started by corpuspits Titled X CPS failure. I have been having about the same problem and got a code a couple of times P0344 (CPS Intermitant Circuit). I am currently trying to trace a short or loose connection in the harness. Mine is an 01 and I found that the coupling above the driverside valve cover about 90% of the pins had corrosion on them. Dont know if cleaning them fixed the problem or if the movement of the wires "fixed" the short I am going to go through the entire harness this weakend with a fine tooth comb to see if I can find any thing else. I'll post the results Sunday

 

Yeah some Cam sensors can go 200K without so much as a hiccup, while others can go in only a few thousand miles. And again, Cam Sensors don't always set codes either!

 

I will look at the connection you are talking about in the morning, I still can't seem to think it is anything else other that a fuel problem. It will idle for hours with no problem. for the most part I can drive it around town and everthing seems ok. when I get onto the highway and really mash on it, it just will not run worth a hoot. The truck has never just died while driving. it seems to be a slower running out of fuel death if you no what I mean. The first time it did this I opened the filter bowl and it was only about half full of fuel. I turn the ingnition on and off a time or two and it fired back up and I was able to make it about 4 miles back home. by the time I got home it had begun to miss again. I have heard the CPS will act differently when going bad. The time mine when out before my truck had good power and ran fine then all the sudden it would just die. I could start it back up and it would run fine for a day or two and then die again. Replaced the CPS at that time and no more problems till now.

Is there any way a return line or somthing could be leaking off fuel. I did notice some fuel in the valley below the filter bowl. just thought it was from the mechanic changing the filter.

 

Could be the filter bowl drain. It has a few O ring seals that are famous for leaking.
Nut

 

BigVic, my 01 did the same thing it was a bad wiring harness

 

Het ed did you find the short or replace the harness i have been searching for about a week for the short...... Trying to put of spending the $$$$$.

 

Bigvic, when your truck started loosing power, was it running real rough, shaking. My truck was doing this under power, Idled fine. and after dropping the tank Twice. I found that the mixing chamber filters were completely clogged up. Removed the hole mechanism, did the hutch mod, and wala, much better. The first time I dropped the tank I didn't know about the tower filters. Everything looked good, tank was clean, screen was clean, put it back together and the same thing happeded. It wasen't till one of the fine folkes on here told me about the tower filters. Dropped it again and that was it. just a thought. It does kinda sound like a fuel problem to me, but I am still kinda new to the PSD.

 

Sorry for not replying sooner, I have been on vacation. I have found the source of the problem after almost $1000 worth of new parts and labor it turned out to be a collapsed fuel line. If anyone is having any of the same problems I was having it may be worth your time to check the suction line between the tank and the fuel pump. My fuel line looked fine upon first glance but if you looked very close you could see what appeared to be a wrinkle in the line on the rubber section near the tank. You could squeeze the line with your fingers and it would collapse and stick together. The truck would idle fine (line open) when you would mash on it, it would suck the line together and cut off the flow of fuel. Installed new line and no more problems.
Thanks to everyone who offered suggestions and possible solutions

BigVic.

 

BigVic,

Thanks for this very valuable follow-up information.

Ya' never know when one of the rest of us will be afflicted by this same thing.

Pop