CPS Failures
 

OK, guys, here goes.

I am going to launch a bit of research on CPS failures. If you are contemplating replacing yours, it's likely that yours is "getting intermittent". If it has "failed completely", you can still participate in this, though it may still cost you the price of a new CPS.

Since these are solid-state devices, and solder joints are "usually" pretty dependable, there's one place that is suspect to me, the connector itself, or more accurately, the integrity of each individual connection to remain extremely low-impedance (almost zero ohms). Due to the relatively-low level of the signal, and it's susceptibility to PCM-confusing "noise", connection integrity is paramount.

Remember that Ford made a production change and there are CPS's for "early" and "late"? They used standard "tinning" on the early connector pins, while "late" is gold-plated. There is no other difference except the part number. You don't want to use dissimilar metals in connectors, thus the different CPS's to match the material used in the truck's harness as it came from the factory.

Ford didn't make that change for no reason. Gold-plating is resistant to corrosion, and gold-on-gold is NASA-quality. Ford wouldn't go to the use of gold-plated pins unless they suspected a problem with maintaining the electrical integrity of those connections. I can't imagine the pressure on the engineer who told management that it was necessary to ADD cost to the product. But they did it, and that should tell us something.

My engine was occasionally "stumbling", and I have a spare in the glove box as any prudent 7.3 owner should have, but not stumbling so bad as to be much more than an occasional irritation (and embarrassment), so I haven't changed it. I just thought about it, waiting for that Round Tuit....

A couple of weeks ago, I thought it was time to familiarize myself with the procedure and location so that when the time came I could go straight to it. I even went so far as to reach up and release the connector's "lock" and pulled it apart. It was clean inside, with no grease, oil, or contaminants of any kind, but I began to wonder about the "insertion pressures" of these connections. the smallest spec of dust could interrupt the signal if the connections aren't tight. I mated and re-mated the connection a couple of times more to knock off anything microscopic that might be coming between the pins and their sockets, and crawled out from underneath with a question in my mind.

Since that day, I have not had another "stumble" of any kind.

Coincidence? Maybe. But that's not what my avionics background tells me.

So, here's the deal. We need a LOT more feedback on this to see if there's anything to what I'm seeing.

I'm asking any of you that are seeing even a hint of "stumbling" to reach up and de-mate and re-mate the CPS connector at least three times, looking to see if it's spotlessly-clean inside.

Then let us know if yours continues to stumble. We may learn something about the Powerstroke's most common sensor failure.

And sure, I may be WAAAAAY off-base, but I believe it's worth investigating, and we certainly have a large test-base group here.

Oh yea, expect to hear me "drone-on" about this until its proved one way or the other. I can cut-n-paste this until the regulars around here are sick of seeing it. Then, bear with me just a little-bit longer, OK?

Maybe you can comment on this to give it a "bump" occasionally, too.

Pop

Insertion may play a small role in the CPS failures. I have a background (many, many years)in IT, hardware tech and QC testing equipment for automotive. I will back you up on the insertion and the microscopic "dirt". Many problems can be overcome by simply removing and re-inserting the connection. I am curious to see what comes up with this thread.

Mine stumbled the 1st time last night coming home from Houston IAH where it was 40 deg and damp. Truck hadn't really had time to get hot when it happend. I have a spare black CPS and am trying to replace it this morning. I have already posted my alternator in the way and broken adapter. I'm letting it soak at thia time.

Jeff,

In the avionics business we referred to this method as "rack and re-rack". Troubleshot a lot of aircraft that way. It confirmed a good box with a bad connection.

If this "pans out", I'm gonna' call it the "Pop Fix". Grab the connector, Pop it out, then Pop it back in..... http://images.ford-trucks.com/forums...lies/smile.gif

Pop

Interesting theory, but well thought out. I'll be following to see how this goes. If my CPS wasn't only about 3 weeks old, I might be able to participate in this one.

Pop, with any luck it will be several years before I have to participate in this test.
Sounds like a reasonable test though. Why spend $60 if a couple of jiggles will do it?
According to that last CPS poll I seem to have a rare truck as there are only a few left with less than 50,000 miles on them.

I just received my new black CPS off of ebay and was going to replace it this weekend. The only trouble I've had is a "split second" hesitation on dead start - initial "lurch" forward, instantaneous hesitation, then "bat outa hell". Don't know if this is CPS related, but figured I'd do it after all the recent threads about CPS. Can the CPS cause this? If so, I guess I could try this and see.

I agree with the potential of your "fix". I'm a UNIX administrator and consequently deal with LOTS of computer hardware. Can't tell you how many times I've had to "reseat" memory, processors, etc.

Pop, I was just wondering if you thought CPS failures could be related to chips and programmers? I should have ask when the poll was active. I know mine went out shortly after I installed my programmer. I do like the idea you have and will certainly try it if mine fails. Also, if anyone has one that they think has failed and has time to play, they could reinstall it and test your theory. I think I was so Pi**d, I tossed it down through the woods along side the road.

I'm pretty certain that a CPS "failure" is in no way related to the installation or removal of a performance "chip". Yes, the CPS feeds a signal to the PCM (Powertrain Control Module) and the chip is added to the PCM, but they do different things.

It would be sorta' like saying, "I got a new mouse for my computer, and now I can only see half my monitor's screen." They both involve the CPU, but are pretty unrelated.

I'm sure there are some who can draw better analogies, and those that could tie a mouse to a monitor, but you get the idea...

Pop

Pop,
You may have something here with the connector issue. With the cyclic temps
the device sees over time i suspect it may have a part in the failure too.
Several folks reported they think high temps lead to the failure of their CPS's.
Also, one person mentioned moisture may possibly be a contributing factor.
I'm currently using a new conductive lube on my automotive/home electrical connections to ensure a good longlasting and reliable connection. I'm thinking
i might like to try it on the CPS connection. It seals out the elements real good
and i remember the boat mechanics in the Coast Guard using it all the time.
Nut

Nut,

Yes! Thermal cycles, too. Thanks for bringing that up!

Moisture, dust, thermal cycles, questionable insertion-pressures, and vibration, all affecting the connector which carries low-level, noise-laden signals that MUST get through reliably for the engine to continue running. Whew!

What an environment for the use of OEM-grade (read: cheapest bidder) connectors. Except for number of pins and physical size, these are basically the same design (except for the plating) as the chassis plug to which the trailer pigtail mates. Not that it's fault-prone, but it has 12-volt power running through it, not square-wave logic signals.

What were they thinking?

Just be very careful about using conductive grease around connectors where you might cause an electrical path between adjacent pins, thus causing further problems.

Pop

I am sure that you are right, but wouldn't a better analogy be " I just upgraded my software to a newer, faster version and now my mouse isn't working right"?
I agree that connections is a very weak link with all of the sensors. I work with computer controlled machinary and HVAC equipment. Most of the sensors and relays are in a much cleaner location than that of our trucks. In a lot of cases where controllers and sensors quit working we pull the connectors and clean with contact cleaner and wha-la it works again.

I loaded up my connector with dielectric grease when I re installed it, in hopes of sealing out dust and moisture. I've made it a habit to use it on any electrical connector that is exposed to the elements.

That'll work JT...i use a combo of conductive lube before i reinstall the connections and then spray dielectric grease to help seal out moisture.
Nut

Nut,

Done with the greatest of care to maintain electrical separation, that is the winning combination, I believe.

It remains to be seen over the long-haul, however.

Pop

I put a very thin limited coating on each conductor.Usually high current applications with big terminals and no chance on shorting as i'm aware of that fact. Works good on the two prongs on my block heater plug at the orange plug.
Nut

NHTSA Open File on Ford Trucks
 

Pop You Might want to keep this in mind also



NHTSA Investigates Ford Trucks for Stalling Problems

March 3, 2006
The National Highway Traffic Safety Administration is investigating seven Ford truck models from 1999 to 2001 because of complaints of engine stalls without warning.

The stalling cause diminished steering and braking ability and has contributed to at least three minor crashes.

As many as 700,000 trucks are potentially involved in the probe, including the E Series Super Duty, Excursion, F Series Super Duty, F-250 SD, F-350 SD, F250 Super Duty and F350 Super Duty.

NHTSA has received complaints from 31 consumers alleging engine stalling because of a failure of the camshaft position sensor.

In many cases the engine would not restart or restarted and stalled immediately.

Consumers reported to NHTSA that once the engine stalled the vehicles were difficult to control because of diminished steering and braking ability.

NHTSA plans to establish the scope and frequency of the engine stalling as well as safety implications and consequences.

WWW.CONSUMERAFFAIRS.COM<O:p></O:p>

http://www-odi.nhtsa.dot.gov/ivoq/


Don J<O:p></O:p>

Yea,

We'll see.........

Pop

Never had one go bad. 31 compliants out of 3,100,000 sold sounds like one hell of a problem!!

cps failure
 

MD, why complain? Ford isn't going to say "Ok we will replace it for FREE!". Consumers take this as part of normal wear, if we like it or not. If everyone complained about it, I'm sure it would be more than 31 people. I for one close to 2 times in 55,000 miles.I'm going to check out Pop's suggestion I think mine is trying to go out now.

jeff

I work with fiber optics allot and find that when we see high attenuation on the fiber, that it is usually a dirty connector. Pull apart the connector and spray with compressed air, replace it and retest. Most times it works. Sometimes the foreign object is stubborn and has to be manually cleaned (the surface of the fiber). When you pull apart the CPS connector, spray it with compressed air to remove any dust or debris. You do realize that if you have any grease on the pins, that dirt and debris have a chance to “stick” to the grease.

OK. Found my problem. After changing the $200 CPS, the truck still would not start. After spending a few days at the shop, It ended up being a $550 repair bill. Some sensor on the injection pump failed. Tiny thing, cost $300, the rest was labor and minor parts.

The NHTSA doesn't investigate something on 31 ordinary old complaints. They must have 31 almost killed someone type of complaints. The article does say due to "decreased handling and braking" which is what does happen when your engine dies. In the poll done here a couple weeks ago there was some 80-90 folks who said theirs died. And a handful of them gave details on how their incident could have caused major harm to someone. So it's not just 31 "whiny" complaints. It's 31 complaints about something that could have had serious consequences. If you ever go look at the NHTSA website for your vehicle, there are tons on complaints. It's the serious ones that NHTSA investigates.

Nhtsa
 

I'll be adding a complaint to the NHTSA's website shortly - I had a CPS die on me while towing 10K - Engine died as I was coming up to a red light. Life got real interesting trying to steer & brake w/o the power assist. Luckily for me I had slowed down early due to what I was towing but, it was still hairy anyway. It could have been really bad if I hadn't slowed up earlier while coming off of the interstate. As it was I stopped about 4ft from the back of the car in front of me after locking up the trailer brakes w/ the controller at the end because I thought I wasn't going to stop in time.

DG

Ouch DG! We need a backup power system to kick-in on engine failure and provide emergency steering/braking control.

Pop,
I realize I'm new 'round these parts...but I've noticed my the engine hesistation and it's stalled on me twice. Once on the freeway driving from Texas to California. On the throttle at 65%, let off to slow, and engine stalled...I instantly flipped the key off, then restarted it, while going 75mph. Hairy to say the least.
The other time same throttle postions, on over half, took it off and stalled. Luckly I was only going about 10mph.
I'm going to try the Blue CPS out. I'll let ya know on the install...

Before you go get a new CPS, try this. Just unplug the connection to the sensor and plug it back in 3 or 4 times. Pop's got a new theory that the CPS may not be failing, but just have a dirty connection at the plug. By unplugging it and plugging it back in a few times, you'll help to clean the contacts. Try that, and post your results. You may end up saving yourself some $$$ too!

Some contact cleaner spray may be a good thing too.

Cps
 

I like pop's theory. That could make a day and nite differance to the strength of the signal. But do keep up the complaints to the NHTSA. No recall was ever won by a few.

My CPS went out about a year back, and at the time I didn't know about this forum. I took it to the local dealership with an intermittant stalling problem. It was really a problem because it would stumble and stall while doing 65 mph on the highway. When they pulled my CPS out of the truck, after 30 minutes of prying on it, the mechanic said "Hmm, look at this, never saw that before". The entire face was raised up with an indentation in it. The new one was perfectly smooth. Something else I noticed after it was replaced was that my cold weather, 1 to 2 minute diesel romp stopped. Maybe I had a different issue than everyone else, but just a thought. Haven't had another problem with it since (fingers are crossed after reading this forum though).

I'm driving a bone stock F250 PSD with 105, 000 miles, bought it new, only problem I ever had.

I can try that as well...
But I still like the minor upgrade to the Blue. Plus, my truck has 148k on it now...and I don't know the history of service.
I think I'd feel better about replacing it as well.
My Devils Advocate thoughts on Pop's theory is that electrical connections, through these "cheap" connectors:
- has been very similar for many different cars. -Not that I'm an expert by any means, but the 70's Bronco's had similar problems, early 80's CJ's had issues with <?xml:namespace prefix = st1 ns = "urn:schemas-microsoft-com[img] /><st1:stockticker><SPAN style=[/img]CPS</SPAN></st1:stockticker>'s, and my Uncle's SC Thunderbird, same thing.- Eventually one has to believe that there is a problem with the actual sensor or the manufacturer.
- The standards that these cheap connectors are made are not exactly aviation quality. It is Mass Produced American...Read: not exactly high quality. There is enough variation in each individual piece made to cause varying results.
- The length of the pins would allow for enough conductivity of electrical impulse regardless of some dust/dirt particles...at least in import applications it hasn't been a problem. I've worked with import engines for almost 10 years now...these engines have far more electrical/computer controlled parts, and far more "cheap" plastic connectors...and there are no significant problems like this in the import engines I have worked with, with the exception of the BMW ECU problem. I think that is the reason I am most skeptical.
Side note to Pop...I mean no disrespect in this post. I'm merely playing a bit of devils advocate with some skepticism on my part. I still intend on pulling the plug, cleaning it with compressed air, a little conductive lubricant and some dielectric grease. I more than willing to be proven wrong...won't be the first time...definitley not the last.
</FONT>

Actually, I welcome all other opinions. You might think of something that I have completely overlooked.

We're actually all working on this together, as we all have a vested interest in having the most reliable vehicle on the streets (no matter what horsepower level you are running)!

Report back and we'll all learn something, one way or the other. ;-)))

I'm waiting on a couple of CPS's that have been "intermittent" to get here. I'm going to deliberately install them to see if the problem continues with them. I'll run them for a month or so, and if I can't duplicate the problem, I'm sending them back to the donors.

Pop

Good idea Pop.

Good deal.
It's raining too hard here to do any work on the truck right now...but as soon as it's a bit drier...you know I'll try it out...

Can someone send a picture or description and a location of this sensor? I thought I was imagining things until I read this forum. I sometimes feel a little stumble, as if my foot slips off the gas.

I have to mirror your experience with European reliablility. I work on VW and Audi for a living and have seen many vehicles go 200,000 miles without ever having to replace the hall effect sender in the distributor. Or anything else in the Bosch Motronic and K-Jet for that matter. They outlast the rest of the car.

Trent..
Just search it out. It'll be quicker for you.
Top of the page on the right side, search this forum for CPS pic or diagram
There's a pic of it somewhere on here...
-t-

Wouldn't that lead you to believe that it was the unreliable connector?

heh...and I wasn't talking just VW/Audi as to foreign. Jap crap, as much as we call it that, is quiet the opposite...

USPS lady brought me an "intermittant" CPS from Jason Lande up in cold-country Minnesota. It's out of a 2002, and has 82,000 miles on it.

Cleaned it up a bit and used the o-ring off my glove-box spare on it. Popped it in and Waaa-Laaa! It fires! Shut it off and went inside. Figure I'll drive it around for a month and see if it's still intermittant or not.

Tonight, went out to go to the grocery, a mile and a half away. Fired right up. I'm getting smug.

Got five blocks. Dead, and no re-starting either.

Flashlight and tool kit on side of busy city street, you get the picture.... and a not-so-smug Pop any more, either.

I've also gotta' rig up some kind of jig with a compass needle or something to give me an idea of the relative gauss for these guys, to see if there's any major variations.

I ordered a package of mil-spec viton o-rings of proper size from McMaster-Carr tonight. I'll have plenty, so a SASE would get one to the first 15 or so guys that want one. They're 1" o.d., 3/32" material.

Pop