Triton V-10 pulsing

[code2e]

Originally Posted by waggintails

In talking to Cliff(my mechanic) he has some of same questions I do. It goes back to a question earlier in this thread. Why did the cc fail at this low mileage. When I replaced the cc, all is good with power, driveablitly etc. The only problem is the surge at low speeds and away from the stop signs. Even though I only drove it a few miles it seems that it is using too much fuel. One of the reasons the cc failed could be a rich running engine. So, on Tuesday with me driving he will hook up to his computer and try to figure out what is going on. I am not too concerned with the aftermarket cc as inspecting the old one it was obviously plugged. In talking to the shop that replaced it they assured me it was compatible with this engine. They are one of only 2 shops around that is highly recommended to do this work. We will see.
fingers crossed. OH, in light of the above, pulled the MAF sensor and it was clean as a whistle. Cliff said being clean does not necessarily rule it out as the culprit. Another sensor which works in conjunction this one is the 02 sensor. We will be looking closely at them along with possibilities of vaccum leaks.
Chuck

Running too rich will cause a cat to overheat and possibly melt it's substrate. Over time the honeycomb will close and plug up. Other failures are from coolant leaks into the exhaust flow, usually head gasket related. Also, oil consumption can plug a cat.

You likely know if coach has been using coolant or oil. If not, rich unburned fuel is most likely culprit.

Your mechanic will hopefully know that scan data for fuel trim will indicate rich or lean. Each bank of the V-10 will show a long term fuel trim and a short term fuel trim number with either a + (plus) or a - (minus) preceeding. Plus means fuel is added and minus is fuel taken away. Long term is "over the long term" and is slow to change. Short term is current and can change rapidly.

The larger the number + or -, the bigger the fuel adjustment. Numbers of say 5 or less are ideal and not indicating a problem. Numbers say 20 or more are big changes caused by something that needs correcting. Long term has been awhile, short term just happened.

Hope that might be helpful.

Also, O2 sensors do wear out. Their reaction time increases with age. I can sure relate to that one. Lifespan is usually 60,000 to 75,000 miles. Hopefully, yours have some life left.

[danhannah]

Today I got my rig back from the mechanic, and they admit they are stumped, and can not figure this problem out. The can clearly hear/feel the surge, but can not fix it. They have given up.

So far they have tested and verified:
Installed 2 new cats
New Ford OEM downstream O2 sensor
Complete vacuum check
PCV and tubing check
Checked every COP and switched a few out, even though they tested pretty good.
Check Throttle position sensor
Cleaned and tested MAF

They do not have the ability to check fuel rail pressure, because there is no fitting, and they did not drop the tank to check the fuel filter.

But at full throttle to the floor, it always runs great, so they do not suspect fuel or fuel pressure issues.

ACTING ON A HUNCH

TODAY I decided to revert my 2013 V10 back to its original CPU programming. I really liked the 5 Star tune - it worked great for many years!

But after removing the tune, the SURGING COMPLETELY DISAPPEARED. So either:

1) The 5-Star tune somehow misbehaves if an aftermarket cat is installed, or:

2) The 5-Star tune deteriorated somehow, and dropped a digit or two, or:

3) Resetting everything back to factory gave me a short reprieve, and once all the sensors relearn and reset themselves, the surge will be back.

I am taking a 200 mile drive over the mountains this weekend, so cross your fingers that the fix is permanent!

Chuck,
Do you have the 5-Star installed?

[danhannah]

Originally Posted by code2e

Running too rich will cause a cat to overheat and possibly melt it's substrate. Over time the honeycomb will close and plug up. Other failures are from coolant leaks into the exhaust flow, usually head gasket related. Also, oil consumption can plug a cat.

You likely know if coach has been using coolant or oil. If not, rich unburned fuel is most likely culprit.

Your mechanic will hopefully know that scan data for fuel trim will indicate rich or lean. Each bank of the V-10 will show a long term fuel trim and a short term fuel trim number with either a + (plus) or a - (minus) preceeding. Plus means fuel is added and minus is fuel taken away. Long term is "over the long term" and is slow to change. Short term is current and can change rapidly.

The larger the number + or -, the bigger the fuel adjustment. Numbers of say 5 or less are ideal and not indicating a problem. Numbers say 20 or more are big changes caused by something that needs correcting. Long term has been awhile, short term just happened.

Hope that might be helpful.

Also, O2 sensors do wear out. Their reaction time increases with age. I can sure relate to that one. Lifespan is usually 60,000 to 75,000 miles. Hopefully, yours have some life left.

Excellent explanation as always - thanks!

I hate to keep harping on this, but everytime you turn of the chassis battery the LTFT for each bank loses its memory. So it starts changing very fast, acting like a STFT, and giving you less info to go by in your diagnosis. Ford should power that CPU at all times, IMHO.

Do you think upstream O2 sensors should be changed out whenever downstream sensors are replaced? The upstream seem to be reading okay.

[code2e]

Originally Posted by danhannah

Excellent explanation as always - thanks!

I hate to keep harping on this, but everytime you turn of the chassis battery the LTFT for each bank loses its memory. So it starts changing very fast, acting like a STFT, and giving you less info to go by in your diagnosis. Ford should power that CPU at all times, IMHO.

Do you think upstream O2 sensors should be changed out whenever downstream sensors are replaced? The upstream seem to be reading okay.

I was unaware of your PCM having a tune installed. Glad going back to factory settings helped. If I had known and knew you had the ability to go back, that would have been my suggestion. Just to eliminate or prove the problem.

As for upstream O2 sensors. They are the prime input to the PCM for fuel mixture. Should last 60 - 75K miles. If they continue to give good readings with factory settings, they should be fine.

Downstream O2 sensors are the cat inspectors. Checking for cat efficiency and setting reediness monitors. Same lifespan, but not so critical.

[LASailing]

Is there any knocking noise during the power loss? It most likely is a intermittent fuel injector. When the injector gets hot, you have an extremely lean mixture and power loss. Eventually the rings will fail in that cylinder and you will hear the piston slapping. Check or replace injectors.

[LETMGROW]

Originally Posted by danhannah

Excellent explanation as always - thanks!

I hate to keep harping on this, but everytime you turn of the chassis battery the LTFT for each bank loses its memory. So it starts changing very fast, acting like a STFT, and giving you less info to go by in your diagnosis. Ford should power that CPU at all times, IMHO.

Do you think upstream O2 sensors should be changed out whenever downstream sensors are replaced? The upstream seem to be reading okay.

Now that you have removed the 5 Star Tune and the driveability has improved, have you thought about contacting Ultra RV and discussing this with them? They may have some suggestions of what parameters you should be monitoring on a road test with the scanner.

[danhannah]

LetMGrow,

That is a great idea. I didn't use Ultra RV, I used 5-star tune, which I guess is a competitor?

I will call them both - see what they say.

There is another guy on this forum who deleted his 5-star tune and immediately re-installed it, and his problems went away. Can the programming degrade over 8 years??

After I take this 100 mile run with the 5-star tune deleted, and if all problems are gone, I will re-install the 5-Star and see what happens.

Thanks for the help.

Dan

[code2e]

Originally Posted by danhannah

LetMGrow,

That is a great idea. I didn't use Ultra RV, I used 5-star tune, which I guess is a competitor?

I will call them both - see what they say.

There is another guy on this forum who deleted his 5-star tune and immediately re-installed it, and his problems went away. Can the programming degrade over 8 years??

After I take this 100 mile run with the 5-star tune deleted, and if all problems are gone, I will re-install the 5-Star and see what happens.

Thanks for the help.

Dan

I would not call the software "degrading", but absolutely, a glitch can corrupt it. If you read how their "tunes" are written, they modify the factory "lookup tables".

Computers in general use "if - then" instructions in their programming. "IF" this happens, "THEN" perform this command. In the operation of an engine, an anomaly can occur, say a temperature reading that is off limits from a modified lookup table. The computer is momentarily lost and can corrupt it's data trying to execute a command based on data it can't lookup.

You restored your PCM to factory. Very unlikely that factory will ever glitch, too conservative. Chances are, reinstalling your tune would go fine. It may fail again, may not. No one could say for sure.

[waggintails]

Originally Posted by danhannah

Today I got my rig back from the mechanic, and they admit they are stumped, and can not figure this problem out. The can clearly hear/feel the surge, but can not fix it. They have given up.

So far they have tested and verified:
Installed 2 new cats
New Ford OEM downstream O2 sensor
Complete vacuum check
PCV and tubing check
Checked every COP and switched a few out, even though they tested pretty good.
Check Throttle position sensor
Cleaned and tested MAF

They do not have the ability to check fuel rail pressure, because there is no fitting, and they did not drop the tank to check the fuel filter.

But at full throttle to the floor, it always runs great, so they do not suspect fuel or fuel pressure issues.

ACTING ON A HUNCH

TODAY I decided to revert my 2013 V10 back to its original CPU programming. I really liked the 5 Star tune - it worked great for many years!

But after removing the tune, the SURGING COMPLETELY DISAPPEARED. So either:

1) The 5-Star tune somehow misbehaves if an aftermarket cat is installed, or:

2) The 5-Star tune deteriorated somehow, and dropped a digit or two, or:

3) Resetting everything back to factory gave me a short reprieve, and once all the sensors relearn and reset themselves, the surge will be back.

I am taking a 200 mile drive over the mountains this weekend, so cross your fingers that the fix is permanent!

Chuck,
Do you have the 5-Star installed?

I am not sure what a 5-star is. I know when I talked to Cliff about it he is not impressed. Anyway, just got back from my test drive with Cliff. He watched his scanner while I put the coach through its paces. He found several issues he is now following up on. The coach is running rich and it keeps trying to reset the trim ratio. He wants to recheck the fuel pressure at operating levels. He didn't go into detail, but he seems confident he is on the trail of a solution. He will get back on it as soon as gets a couple of ambulances out of the shop. Stay tuned.
Chuck

[code2e]

Originally Posted by waggintails

I am not sure what a 5-star is. I know when I talked to Cliff about it he is not impressed. Anyway, just got back from my test drive with Cliff. He watched his scanner while I put the coach through its paces. He found several issues he is now following up on. The coach is running rich and it keeps trying to reset the trim ratio. He wants to recheck the fuel pressure at operating levels. He didn't go into detail, but he seems confident he is on the trail of a solution. He will get back on it as soon as gets a couple of ambulances out of the shop. Stay tuned.
Chuck

Your long term fuel trim is changing because it's trying to get the fuel mixture corrected. Something in the fuel delivery is off and delivering the wrong amount of fuel.

Could be fuel pressure is off. That would be a pump issue or fuel pressure regulator issue. Fuel injectors could also be dribbling on, suppling too much fuel. Injectors are little more than solenoid liquid valves with spray tips. If the solenoid doesn't close completely, fuel will flow thru between injections and your mixture will be rich.

The closer your fuel trim numbers are to zero is where you want to be.

[tiffy2000]

That isn't the first time I've heard of someone going back to stock tune and having it take care of a issue

[waggintails]

I haven't forgotten all you out there waiting on a diagnosis of my engine issues. Just be patient for a few more days. Cliff has fuel trim issues diagnosed and now within specs. That didn't clear my problem but it sure made the coach run better. I'm sure the coach has been running rich which contributed to the cat failure. However, I still have the surging problem. He wasn't able to stay on it last week as he was backed up. I think I told you at the beginning that he did not work on motor homes but would take a shot at mine. I ask him last week if he was done with mine now? His comment was "Youve got to be kidding! I am into it now and will keep after it until I solve it. So, stay tuned.

Chuck

[JoeMed]

So I have been following this thread closely as my coach has had very similar issues. I am very happy to report It is now running great! Here's what has been done over the past month.
Catalytic converter replaced with high performance Magnaflo (stock had failed)
All plugs changed
2 coil overs changed (found cracked housings)
Fuel filter changed
Air filter changed
Fuel pressure regulator replaced
Fuel pump replaced. (Low fuel pressure on the rail)
After all this the coach started and ran better, but still no power and unable to run above 40 mph.
Mechanic went back and ran scans, found nothing at idle.
Coach stumbled under load. The culprit was a faulty air cleaner that had failed and was collapsing under load. Air filter was changed and coach is now running better than ever!
We have a trip planned to the coast next week and I'll post an update on how the coach does, including Fuel mileage.
Hope this is of some value.
Joseph

[waggintails]

Originally Posted by JoeMed

So I have been following this thread closely as my coach has had very similar issues. I am very happy to report It is now running great! Here's what has been done over the past month.
Catalytic converter replaced with high performance Magnaflo (stock had failed)
All plugs changed
2 coil overs changed (found cracked housings)
Fuel filter changed
Air filter changed
Fuel pressure regulator replaced
Fuel pump replaced. (Low fuel pressure on the rail)
After all this the coach started and ran better, but still no power and unable to run above 40 mph.
Mechanic went back and ran scans, found nothing at idle.
Coach stumbled under load. The culprit was a faulty air cleaner that had failed and was collapsing under load. Air filter was changed and coach is now running better than ever!
We have a trip planned to the coast next week and I'll post an update on how the coach does, including Fuel mileage.
Hope this is of some value.
Joseph

Thanks for the feedback. The air cleaner was one of the first things I changed out. My coach runs fine over 40 but does its stumbling at take off then levels off at cruising speed.