New Ford 7.3L engine problems

[Springhook]

Originally Posted by TDeakins

Sounds like my previous engine. Took Ford 92 days to diagnose and replace that engine. Your symptoms sound like mine. In my case it was cylinders 3 & 7 that would not hold compression. The replacement engine is night and day different but I’ve not pulled any long hauls yet. MPG has improved considerably, too. If you haven’t already, you may want to contact Ford directly.

Thank you. Yes, Ford customer service and factory are now involved. Mine was just idling rough. No CEL but Ford service OBD scanner revealed misfires across ALL 8 cylinders.

[F4Gary]

That sounds like an electronic brain problem.

[TeJay]

I'm still very much surprised how poorly these dealer technicians have become as far as the ability to diagnose. I have very good reasons to question it as well.

Back in 1980 when all manufacturers were required to offer all engines that were computer controlled everybody in service as well as the education field was in a turmoil.

The industry was throwing all this new technology at the techs so fast they had a very, very difficult time keeping up. We educators were scrambling to take classes summers, evenings and any other time we could find them being offered. The learning curve was very, very steep. Besides the obvious the technology would also change from month to month as new technology was being thought of designed and introduced. The next bad aspect (IMHO) was the customers were being used as test subjects.

The emission guidelines were on a step by step progression. One year the CAFE was this or that and the next year it was changed and so on. That forced the manufacturers to continue the changes to meet that years standards but yet prepare for the changes coming the next year.

A perfect example was the carburetor. Once you learn them that's kind of it. I won't go into all the details. The CHOKE system to richen the fuel mixture on cold starts. The ACCELERATOR pump system to reduce lean fuel when the throttle was suddenly opened with an inrush of way to much air leaning out the mixture. Additional fuel was mechanically pumped into the intake.

In 1980 the carb was essentially the same but electronically controlled. The district had to spend thousands of dollars so we could get all the necessary tools to work on them. After 1 at the most 2 years they went to the TBI (Throttle Body Injection) That really changed the carb. The injector setting on top of the carb was pulsed to regulated the amount. I believe oxygen sensors were introduced sometime in those first few years so the fuel mixture could be somewhat determined and therefore regulated.

Eventually they went to FI (fuel injection), then DFI or Direct FI, Then into PFI or Ported FI. Finally as I predicted the industry kind of settled down by 1996. The engines were getting decent fuel mileage while meeting emissions. Things were staying together and fewer things changed from year to year. You'd think by that time the techs could slow down and really learn what they were doing so they could diagnose.

Back in 1977 or so we had our first motor home on the Dodge chassis (360 engine) and I had to take it in to a dealer. One of the mechanics and I were talking and he told me. I diagnose very little. I use my past experience and know how things should sound to decide what needs to be changed. I'm a parts changer. I don't believe I'm going to make it in this new environment.

We lived in the Detroit area my first 10 years (1972 to 1982) of teaching automotive. EVERY clinic I attended for the next 3-10 years always emphasized the need to use symptoms to diagnose what's wrong. Don't just be a parts changer.

Another very good example. When the first vehicles were computer controlled the control was called a, "Brain." It didn't think but it did monitor inputs and make adjustments. Typically when things didn't work and codes were set the, "Brain" was replaced. Detroit wasn't stupid. All Brains were sent back to a service center and checked for defects. More than 90% of those so called defective brains were just fine.

In my own career over the next 30 + years I believe we changed 2 controls and I'm not sure either one of those were bad. They really were not a problem.

So here we are 42 years after the introduction on computer controlled engines and the techs still don't know or won't try to diagnose. They have become or still are parts changes.

The biggest part of the problem is the perception of a blue collar job and of being a car mechanic. Smart college bound kids are discouraged from taking shop classes. Even when they insist that's what they really want to do.
I had several students who were highly discouraged from taking my classes. Every semester the counselors tried to talk them out of it.

It is still very much frowned upon by society, parents and very, very, very often discouraged by HS counselors as a viable career option. I fought that crap for all my 35 years. We were the dumping ground. Was then and still are. Everybody is going to college, get a job and make a fortune!!!!

[bross]

Originally Posted by TeJay

I'm still very much surprised how poorly these dealer technicians have become as far as the ability to diagnose. I have very good reasons to question it as well.

Back in 1980 when all manufacturers were required to offer all engines that were computer controlled everybody in service as well as the education field was in a turmoil.

The industry was throwing all this new technology at the techs so fast they had a very, very difficult time keeping up. We educators were scrambling to take classes summers, evenings and any other time we could find them being offered. The learning curve was very, very steep. Besides the obvious the technology would also change from month to month as new technology was being thought of designed and introduced. The next bad aspect (IMHO) was the customers were being used as test subjects.

The emission guidelines were on a step by step progression. One year the CAFE was this or that and the next year it was changed and so on. That forced the manufacturers to continue the changes to meet that years standards but yet prepare for the changes coming the next year.

A perfect example was the carburetor. Once you learn them that's kind of it. I won't go into all the details. The CHOKE system to richen the fuel mixture on cold starts. The ACCELERATOR pump system to reduce lean fuel when the throttle was suddenly opened with an inrush of way to much air leaning out the mixture. Additional fuel was mechanically pumped into the intake.

In 1980 the carb was essentially the same but electronically controlled. The district had to spend thousands of dollars so we could get all the necessary tools to work on them. After 1 at the most 2 years they went to the TBI (Throttle Body Injection) That really changed the carb. The injector setting on top of the carb was pulsed to regulated the amount. I believe oxygen sensors were introduced sometime in those first few years so the fuel mixture could be somewhat determined and therefore regulated.

Eventually they went to FI (fuel injection), then DFI or Direct FI, Then into PFI or Ported FI. Finally as I predicted the industry kind of settled down by 1996. The engines were getting decent fuel mileage while meeting emissions. Things were staying together and fewer things changed from year to year. You'd think by that time the techs could slow down and really learn what they were doing so they could diagnose.

Back in 1977 or so we had our first motor home on the Dodge chassis (360 engine) and I had to take it in to a dealer. One of the mechanics and I were talking and he told me. I diagnose very little. I use my past experience and know how things should sound to decide what needs to be changed. I'm a parts changer. I don't believe I'm going to make it in this new environment.

We lived in the Detroit area my first 10 years (1972 to 1982) of teaching automotive. EVERY clinic I attended for the next 3-10 years always emphasized the need to use symptoms to diagnose what's wrong. Don't just be a parts changer.

Another very good example. When the first vehicles were computer controlled the control was called a, "Brain." It didn't think but it did monitor inputs and make adjustments. Typically when things didn't work and codes were set the, "Brain" was replaced. Detroit wasn't stupid. All Brains were sent back to a service center and checked for defects. More than 90% of those so called defective brains were just fine.

In my own career over the next 30 + years I believe we changed 2 controls and I'm not sure either one of those were bad. They really were not a problem.

So here we are 42 years after the introduction on computer controlled engines and the techs still don't know or won't try to diagnose. They have become or still are parts changes.

The biggest part of the problem is the perception of a blue collar job and of being a car mechanic. Smart college bound kids are discouraged from taking shop classes. Even when they insist that's what they really want to do.
I had several students who were highly discouraged from taking my classes. Every semester the counselors tried to talk them out of it.

It is still very much frowned upon by society, parents and very, very, very often discouraged by HS counselors as a viable career option. I fought that crap for all my 35 years. We were the dumping ground. Was then and still are. Everybody is going to college, get a job and make a fortune!!!!

Well stated, good book to read:

Shop Class as Soul Craft: An Inquiry into the Value of Work
Shop Class as Soul Craft

[Kluffinator]

Originally Posted by Kluffinator

Ok. So it has been over 3 months since the RV was tied to the Ford Truck dealer and to date they still haven’t figured out what is causing it to go into limp mode. They have replaced spark plug wires (which I had already done), the crankshaft position sensor, camshaft position sensor twice, chase down the wiring harness, and who knows what else. They tell me that the case have been escalated within Ford Technical and that Ford is writing code to put more diagnostic features in their scan tool.
Mechanically the engine seems to run fine, until they drive it. I’ll keep you all posted whenever they figure out what is going on with it. Only 3,800 miles on it.

Ok. As promised I am providing a follow up and hopefully this info will be useful to you others that have the new F-53 Chassis as something to inspect for.

After almost 5 1/2 months at the Ford dealer and much stress and angst, the problem was resolved and RV is back on the road.

Turns out it was not an engine issue at all per se but a wiring one. After having the FORD FSE run numerous checks and try numerous fixes of swapping parts including coils, plug wires, Crank and cam position sensors and a PCM, the shops technician went back over the wiring harness inch by inch and found where the loom (14405) had come loose from its holder, about six feet behind the transmission and would rub on the top of the driveshaft. Circuit LE230 BN/BU wire that is the Voltage reference wire for the FTP sensor was contacting the driveshaft and that was causing the PCM to go into limp mode.

So, for those of you with this same chassis it might be well advised to check the security of the wiring looms near the driveshaft when you do your undercarriage inspections. I know I will from now on.

[Pesky1]

Thanks for the resolution info. IMO 5 months to troubleshoot anything sold by your company is unacceptable. I mean, this wasn’t a mom and pop service shop, they are supposed to be the experts. Oh well, in between shoveling snow I will be checking everything under my coach for sure.

Enjoy a week or two back in the Gulf Shores with Dulcinea and the beagles and wipe thoughts of this mess from your mind. Glad you got it sorted out.

[TeJay]

IMHO. Just another example of mechanics ( I tend not to use the word "TECHNICIANS") especially when the workers are just swapping parts until they can get it fixed. Diagnosis or thinking based on symptoms does not seem to be in the vocabulary of MECHANICS.

Spark plug wires will give a specific code and will probably not be a limp in mode. The owner already changed the wires. I guess he's not smart enough to do it correctly. Either a wire is connected properly which can be checked easily. If one is not it will give a code for a miss. The crankshaft and camshaft sensors should have given specific codes as well and the cam shaft sensor had already been changed more than once. I guess ignition spark coils were also changed. Again a specific code for a misfire would be given if a coil were failing.

Keeping known defective specific sensors like cam, crank, throttle etc can be another way of checking for defective parts. They also swapped the PCM as well.

This was a unique set of symptoms but following all the swaps with not good results the next step should or would have been to wiggle all wiring harnesses and or double check all harness connections. These mechanics didn't use a newer obvious technique which was to wiggle and check the positions of all wiring harnesses. In past years that might not have been obvious step but today it is.

Diagnosing in todays electromechanical world takes a different set of skills and techniques. Most good Technicians know when a specific sensor is defective based on past symptoms. Even when a sensor is intermittent. Tapping an intermittent sensor with a screwdriver can get it to fail. Did any one report trying to do that?

One of my "X" students does just that. He's a harness wiggler and tires to think logically, outside the box and not just a parts swapper.

"They tell me that the case have been escalated within Ford Technical and that Ford is writing code to put more diagnostic features in their scan tool."

I do like the above quote. At least Ford is using this example to improve their SCAN tools. Maybe they just are not getting enough specific data to do a good diagnosis. I'm out of the field for 16 years and sure don't know much of what has and is still happening.

At first much of the public thought the PCM would tell the technician specifically which part to change but that was not the case. The PC only alerts the technician to what is happening but not very specific. Yes, a misfire is specific.

Not unlike what the nurse and doctor can determine when you go in for a checkup. They tell what is wrong with you by you explaining the symptoms and them giving you specific tests. Once they evaluate the results then they may be able to diagnose what is wrong. That also takes a lot of practice and training.

[edge68474]

Good info and thank you for some auto mechanics history TeJay.
Since I became a owner of a RV, I have become a wire wiggler. Seems half the problems on my coach are wires. Now I am not saying I have a lot of problems, I do not. I think my HR is a very good coach.

[Kluffinator]

Actually I am smart enough to change a spark plug wire. Especially on something as easy as this 7.3. Just to be clear. And that did solve the misfire that I had previously.

It wasn’t until we went in and after having expressed our heartfelt exasperation and they finally asked what had been happening around the time it failed did they once again go through the wiring harness. When I’m our discussion it came to light that it seemed to fail in conjunction with letting up the throttle did they focus in on issues that might occur with the frame flexing and also directed attention to the dynamic controls system.

A bit of paying more attention to the customers observations when I first brought it in may have gone a long way to resolving earlier. But then a whole month went by from when it got towed to when they actually started working in it. Such being the overall shortage of mechanics.

[Chargerman]

Why the heck would they design it so that the wiring harness goes over the driveshaft? It’s like this was the first chassis they designed. Same goes for the plug wire issue. More examples of the generational torch passing being lost.

[Rockwood27]

Originally Posted by Chargerman

Why the heck would they design it so that the wiring harness goes over the driveshaft? It’s like this was the first chassis they designed. Same goes for the plug wire issue. More examples of the generational torch passing being lost.

Many years ago, I went to an engineering conference in Michigan. I was sitting at a diner table with a Professor of Mechanical Engineering from the U of Michigan. He did a lot of consulting work for the "new hires" at the various auto companies. The new engineers would call him when they ran up against a design problem. He said that he would go into their office/cubicle and first scan the textbooks on their shelves (new engineers would love to proudly display their textbooks).

Typically, a Mechanical Engineer would either be disciplined in the material sciences or design mechanics. If he saw an abundance of material books, then it became a "design mechanics" problem. If he saw an abundance of design mechanics books, then it became a "materials" problem. He always made money and the new engineers never learned!

Sent from my SM-A515U using iRV2 - RV Forum mobile app

[Springhook]

Latest update is Ford factory recommends changing heads and lifters. Supposed to hear back this Thursday, 4/22.

[Chargerman]

Oh boy. Sorry to hear but it reaffirms my practice of not buying a first year of a new powertrain, especially from Ford. I learned the lesson the hard way also.

[TDeakins]

Originally Posted by Springhook

Latest update is Ford factory recommends changing heads and lifters. Supposed to hear back this Thursday, 4/22.

They tried that when my 7.3 failed. Did not work. Swapped both heads. Compression failure on cylinders 7 & 3 persisted. Ford - after nearly 90 days of “shotgunning” the problem - ended up replacing the entire engine. Although Ford would not tell me what final diagnosis brought them to that point, the lead tech at the dealer said the cylinders were milled wrong. A problem that cannot be repaired. The replacement engine is a “3rd generation” whereas the one that failed was a “1st generation”, or so I was told. What happened to “Quality is job #1”? Guess that doesn’t resonate any more. Oh, and to add insult to injury; don’t expect Ford to make any amends for keeping you vehicle out of service for months either. Performance on the new engine is underwhelming relative to published specs and hype. The aluminum body is not nearly as strong as the steel. I’ve owned a lot of ford trucks in the past. Swore by them. Not anymore. Next truck won’t be a ford.