2003 Excursion, 7.3L, 156,000 miles.

Cold startup: Click on ignition, let WTS light go out, start engine, let idle for a couple of minutes, take off out of driveway, THEN at almost exactly the same spot on the road (only three houses down from our yard) the vehicle starts to shudder and the engine misses badly.

Action: When this happens, and it does not happen every day, and it only happens under the conditions described above, we can either 1) shut the engine down and restart it and everything is fine, or 2) stop the vehicle and let it idle for a few more minutes and then everything is fine.

Additional Context: I did the intank mods several weeks ago, but the above problem happens at both nearly full and 1/4 tank fuel levels. I did not re-install the screen at the pickup foot in the tank, and have not yet installed the pre-pump filter. No other work has been done to the vehicle in the past several weeks.

The problem described above first happened about a week ago, and is becoming more frequent (did it both yesterday and today).

My gut feeling is to replace the CPS, but I want to get input (either confirmation or other ideas) from the rest of you guys while I'm at work today since I can't make the CPS swap out until this evening when I get home.

Let me know what you think.

Thanks

 

When my CPS went out, it just killed engine like I turned the key off. Did you get any codes, Pete?

 

Honestly, Rick, I've been running in so many directions I haven't even run the codes yet. It's my wife's DD, and it has simply slipped my mind until she called earlier this morning to tell me "it happened again this morning, and I forgot to tell you last night that it happened yesterday morning as well".

I will hook up tonight and see what I can find, and probably just go ahead and toss my spare CPS into the engine to see if that clears it up.

Do you have any thoughts on what else it might be, Rick?

 

I think everything that goes bad is CPS related. Ive had 2 die in 2 months of time. One time it wouldnt start. and the other it bucked and slammed till it just shut off when i was driving like i just turned the key off. If you change it get yourself a good one because you dont want any problems in the future!

 

I have either one or two gray's right now, but am getting ready to get another one or two blacks from Clay so I can have the "original" option.

 

Do you get a SES light when the engine runs bad ?

 

My CPS has thrown and light and hasnt. You cant base it off that.

And if you wanna save some money they have a CPS out better then the Black for half the price. Ghig posted about it last week.

 

I am not... I just was thinking if he had a SES light, it kinda sounds like the UVC connector has come loose... I had the same thing happen a couple of years ago.. The condition is usually intermittent .

 

I think it's a little early to start talking IDM, PCM. I would put your spare CPS in and see what happens and get the codes read.

 

Well, I ran the codes and there weren't any that were of any significance. AIH code because I've deleted the AIH, but that's all.

We took out the CPS (it was a light gray unit from the recall), and I installed a light gray unit I had run in my truck for nearly a year with no trouble. I was amazed at how much smoother the engine ran with the new (used) CPS. I was soaked from having been laying on the wet concrete, so I didn't take the time to hook up AE to see if anything changed.

With the "old" CPS, I got zero's to 0.1 on all but cylinders 3, 5, and 8. No.3 was running around 1.2, No.5 was running around .7, and No.8 was running around 4.5-5.2. I'll check AE on it tomorrow after finding out if my wife gets the same symptoms or not in the morning.

As far as I can recall, we never have gotten the SES light when it stumbles like it has.

 

Well, I do have an extra CPS now, that we know has been working for a long time. I don't know if it would be worth it, but if the ex is still getting that miss, we could always switch out the current CPS for my old one, just to see if it changes anything. Just throwing it out there...it's in my glove box so you can have it tomorrow if you want it. As long as I keep an extra one with the truck, that's all I need.

 

Thanks, Benjamin, but I also have another brand new unit (light gray) in the glove box, so I'm good for now.

 

I hope that's all it is Pete. Fingers crossed.

 

When my stock CPS started its shutting off a mile or so up the road after startup, no SCS light here at all, just died then all the cluster lights lit up. Seemed like it was the way the truck was telling me there was a problem. These things do go nuts their own special way, no warning or a skip a beat miss or something. Seems kinda strange you can't get a code or oddball reading when these things are happening, my SC handheld didn't pic up anything either if I recall, not one hundred percent sure but I'm going with that. Good luck Pete.

 

Is there a difference between the international CPS and the Ford CPS? Can someone provide me with the part numbers for the international CPS as well as a place I can buy one? I have been told or read that the "new-improved-better CPS" is black with a purple ring. I can not find them on partsguy site. My truck has the blue-grey CPS in it now.