Greetings from lack of power'ville.

I am praying 🙏....maybe a little begging going on too 🫶 that someone can help me narrow down or prioritise my process of elimination list to hopefully rid my truck of the gremlin it has harboured somewhere?

Ol faithful black beauty is a 2006 5.4l Triton F250 XLT I believe the 2V with just over 240k on the clock has suddenly decided it does not wish to tow anymore and, also is not unlike me in the sense it only wants to work at night time and sleep all day.

Truck has been an awesome work truck for the last 3 years I have owned her.
It had a slight lack of power issue about 2 years ago that was solved with a new set of spark plugs. Hasnt missed a beat till now.

Started with a humming noise which we eventually got sick of and fitted a new IAC valve. Which did shut that up, then came hesitation, back firing & throwing Bank 1 & 2 lean codes and CEL.

Changed spark plugs & Fuel filter & had the injectors cleaned. Cleared codes.

It was heaps better but would still sometimes slightly hesitate while towing, and up hills if I asked for more power.
no engine light or codes yet.

This is all towing our bumper pull trailer which is considerably lighter than my old gooseneck trailer that it towed beautifully.

Then, We cleaned the MAF sensor (with Mass air flow cleaner) checked for vaccum leaks etc.

It did a few trips hauling horses and didnt miss a beat...had great fuel economy and seemed to just purr along. I prefer to haul at night time, less traffic and cooler for the ponies.

I had a long trip about 3 weeeks ago and started out in the early afternoon, she played up like a second hand lawnmower. It would go but i sort of had to find a sweet spot in the accelerator and eventually it would chug on up to cruise along ok. Then it would just get worse & worse until loss of all acceleration and I'd have to pull over for a about an hour then it would be ok again for a while, then do it again.

That was a reaaaaallyy LONG trip.

Got home......finally......replaced all COP's (Good brand non genuine).

It played up worse.......I read somewhere that the computer needs to re learn running parameters? Not sure if that's accurate but I kept driving it on short trips no trailer & It got better, not perfect & sounded like a second hand lawnmower but it didnt get to the total loss of power.

At night time its a different truck i swear.....the cooler the weather the better it runs and will go all night. Last week my daughter and hubby both had car accidents a day apart.
i drove 2300klm round trip over 2 days to collect them, I towed a car trailer for about 200klm of that trip without any problems ran like a brand new truck......i kid you not.....I kissed the dash when i got home and thanked her for being a good truck.

I hauled to a local rodeo bout half hour away last weekend and it played up 5 minutes from home but again i could find a sweet spot in the accelerator and it would chug a lug up to cruise along ok.....i dreaded traffic lights turning red because it would be very lethargic taking off & not smooth it would surge and feel jerky.

I monitored live data whilst towing at night and the Short & long Term Fuel was very erradic.

I have another long trip next weekend towing horses and I REALLY don't want to do it chug a luggin at 30klms an hour.

I am going bald pulling my hair out. I will be very grateful for any info you can give me to solve this issue. Hubby is ready to sell it for the best offer but I'm not there yet... it's been so sick coughing, spluttering, surging and jerking but still get us to our destination...........eventually.

I do have video of the live data and of it being a brat, but I read here you need an off site host for media? I will look into that if its needed for diagnosing. It is only a basic reader tool.

Thank you everyone I think that over explains things enough. 🤣 sorry it's long.

Sammy ❤️

 

A 2006 F-250 5.4L would be a 3V engine. A 3V 5.4L wouldn't have an IAC. Is "2006" a typo?

 

Thanks for your reply. 😀 Photo attached is what we replaced. Definitely a 2006 petrol 5.4l I will have to check but a while ago i needed to know if it was 2v or 3v and i remember checking the marks on the air intake that is suppose to indicate 2v or 3v and ours was 2v. I will have to double check that now. 🤔


Edit: So it doesnt have 3V on the air intake box and the coils have the bent/angled rubber boots.
I did buy it second hand so maybe they swapped the motor out? Might be worth a VIN check.
This would explain why the listings for parts are all wrong at my parts store. 🤣

 

Super Duty gas pickup trucks 2005 and newer came with 3V engines, the 5.4L V8 and the 6.8L V10. 1999 thru 2004 were 2V engines, on pickup trucks anyway. E series vans, different story, as are motorhome chassis vehicles. F150s got the 5.4L and 4.6L 3V engine in 2004. Non US/Canada vehicles can have just about anything.

Aside from that, based on your description, my first guess would be that you have a failing catalytic converter. It’s heating up and restricting exhaust flow.

 

Thank you for your reply.
we put a 3inch exhaust with a straight through converter on it about 2.5 years ago. Being a bit of a rev head I wanted it to be louder. 😬

What happens if you remove it completely?

hubby found a few hoses that look brittle he took them off to replace I noticed they were really thickly covered with black soot. The hoses led to the charcoal filter. If the vapour canister has failed could that clog the engine or cause vapour lock? Sometimes when I re move the fuel cap it makes a hiss sound but not all the time. We also noticed that when it had a full tank of fuel, it wouldn't play up as bad.

And when it got low if we cracked the fuel cap and drove with it not sealed it would be less symptomatic.
I have had this truck to several mechanic's but they have less of an idea than i do, I've spent ALOT on diagnostics with no results.

Can anyone tell me what the readings should be on a scan tool in live data mode for this truck?

Could there be any clues to give us better direction at all?

Sorry if I'm not making sense, I have done so much research I'm starting to confuse myself. 🤣.

Thank you so much for your help.
This seems a common problem, so I'will
make sure to post updates right to the end.

If we ever get there...🤣

 

Just remove the catalytic converter to test if it is the issue. A failing cat may not throw an error code.

I’ve never heard of a clogged charcoal canister causing drivability issues. It usually causes difficulty in filling the tank. But, the hiss is a clue that you are probably on the right path.

 

Check fuel pressure, I had an old Bronco II acted similar and an Aerostar do the same sorta things when the fuel pumps were going out. The Bronco would run great when it was cool prat night but let it get 85 or better and forget it.

 

I second this opinion. I have a buddy with a 1990 F250 with the 302. He also had a high-flow catalytic converter and had very similar symptoms to yours. It would idle pretty good, but as soon as you tried to give it a good amount of throttle, it'd bog down and surge pretty bad. He took the cat out and cut it open and sure enough, the material inside of the cat had come apart and clogged the cat up which restricts the exhaust flow

Also to answer your question as to what happens if you remove the cat, the truck will be really really loud, but it'll be fine to test drive it to see if a clogged cat is the issue. Also, does the truck only have 1 cat or multiple? I seem to remember another buddy of mine who had a 5.4 super duty had 2 cats from the factory.

 

Thank you, I think it only had 1 cat & 1 muffler.
now it just has the muffler.
Hubby bashed out the internals of the cat yesterday and then had to leave for work so I'm about to bolt the exhaust back up under it and see how it goes.
i dont mind it being loud, as long as its not all noise no go. 🤣

Pray for me, I just need it to be good as gold for the next 2 months with a few long hauls, mostly by myself.

I will let you know how I go.

Again Thank You SO much for your help & expertise.

 

This is something that crossed our mind with the erradic fuel data on scan tool but couldn't figure out why it would be better at night? The motor runs at the same tempreture day & night.
what was causing the fuel pressure problem?
Faulty fuel pump?

 

Well.....I just took the truck for a spin and put it through its paces and tried to recreate its symptoms and.......I couldn't get it to do what it was doing prior to punching out the cat.
so hopefully 🤞 it's solved.
at 100klm/h up hill i planted my foot and it just opened up and boogied on up the hill.

Taking the horses to the beach Thursday morning so ​​i wont know for sure until then if its 100% OK, but prior to this fix it wouldn't cope with foot down to the floor at 100 it would just die in the **** and go no where, so i reckon she's healthy again.

One last question, its actually not that loud and sounds really good and seems to have alot more raw.power. Is there any need to install a new cat?

Thank you so much for all your help a cat failure wasn't even on my list and I don't think I ever saw it mentioned in my online diagnosing attempts so I would have been going around in circles for a long time.

This forum is a valuable resource for F truck owners. I look forward to learning more.
Cheers

 

You’ll need a new cat if you’re subject to vehicle/emissions testing for license renewal. If you don’t need an inspection, then technically you are in violation of federal laws, but chances of being caught are pretty much zero. *wink wink nudge nudge*

 

G'day Everyone,

Sorry for the late update, I wanted to make sure we had actually found & completely fixed the problem.
Everytime we fixed what we thought or were told was the issue causing the drivability problems, the symptoms would disappear for a period of time. Then return with a vengeance. The last time before this latest fix, it was undrivable and had to be trailered to mechanic.
It cost us another $2400 but the ol girl has a brand new fuel pump and is running like a brand new truck with no reoccurance.
Mechanic also replaced crank angle sensor which he noted was a pain in the rear end to do.

So all up it cost us about $4k AU which included the following repairs in order of replacement.

Injectors removed and cleaned
New coils
New spark plugs
New fuel filter
Tank removed and cleaned
New fuel lines
New fuel pump
New crank angle sensor

I guess it was always the fuel pump and we prolonged its total demise by replacing all the other fuel components which i guess bandaided the problem for a while.?

Happy F trucker I am.....

Have a good one