Ford v10 loses power

[Redram99]

Hi all!!
I have some power issues.
2010 e450 class c with the v10 and 90,000 Kms.

A couple of times in the past the engine has disliked aggressive acceleration and seems to kick into safe mode. This has happened when I am merging onto the highway and holding it wide open to get up to speed. It seems to drop from producing 300hp to about 200hp!! However, it’s only happened a couple times and if I pull over shut it off and restart it is all good again. This only happened 3-5 times over 3 years.

Recently, we did a 3000km trip around bc and on our way home, it started to act up but would not get better. We stopped for a little break, it was running like a champ and then hit the road and it “detuned” itself. Tried the shut off and restart and it would be good until I hit the first hill and as soon as I pull hard on it it detunes again.

As long as I can keep it in high gear it will pull hard. As soon as it downshifts and the revs pop up to 3500 it will pull hard for a couple seconds and then you can feel it drop power. And then will not smarten up for 10km or so.

It also wouldn’t provide any engine breaking coming down hill. The tranny would downshift but it would just go faster on hills that the engine would normally hold the desired speed.

Motor sounds great.
Not using oil.
Idles smooth and smooth at 4500 rpm.
Not overheating.
Tranny shifts good.
No codes

Any ideas?
I am going to do a air and fuel filter.
Thanks.

[Yosemite_Sam1]

tobydad wrote:
One possible problem could be the fuel filter being partially clogged and as you accelerate the increase in gas cannot make it through the filter. Always start with the simplest solution first.

Yeah, you want the simplest first before you bring it to the mechanic and scare you that the problem is a very pricey compression loss due to worn out cylinder that needs re-boring.

[DougE]

If you lose power trying to speed up or go up a hill the most common cause is poor fuel delivery due to a clogged fuel filter. If you are running at a constant speed and power drops off the most common problem is a failing fuel pump, especially if the fuel tank is mostly empty. After that go to hunting ignition problems.

[Hank85713]

I have 12 winnebago, but also had fuel pump failure last year. Yours kinda sounds the same except after a while mine would not start. Pulled codes with none to be found, ended up at a shop on 4th july weekend. Could not get codes even with the ford scanner. Anyhow finally replaced the fuel pump relay (after the fuel pump, tps couple of other things) and all was well.

Yes you could be due a tuneup, but see if you can get the relay tested or just replace as they are not that expensive. A lot cheaper than trying to R&R fuel pump. I think at ford they were like $65 US same at Oriellys. Autozone was $200+!

[Sam_Spade]

tobydad wrote:
One possible problem could be the fuel filter being partially clogged and as you accelerate the increase in gas cannot make it through the filter. Always start with the simplest solution first.

Possible fuel pump issue too......along with lots of other things.

Should have a code reader connected. There may be trouble codes set that don't light any warning lights.

Outside wild guess: the rev limiter is malfunctioning and cutting off at too low an engine speed.

P.S. Actually "flooring" the gas pedal might not be a good thing to do, just in general. Try not pushing it quite that far.

[ron_dittmer]

One very simple thing you want to inspect for.....

Remove the oval air filter tube from the front plastic shroud area and inspect the hole it attaches in to. That hole should be free and clear of black plastic. The shroud itself has a plastic flap that if the shroud was removed and flap not position properly when being re-installed, there is a serious air flow obstruction.

I don't recall what year it was, but some time after 2007, Ford had a recall on this very thing. During that model year for a number of months, someone on the Ford assembly line was mounting the black front shroud with the flap not folded back properly, causing that air intake obstruction. Every E-series was recalled and inspected to make sure the flap was folded back during assembly.

With our 2007 E350, we ended up with a large bird plastered on our radiator. I removed the shroud trying to gain better access and sure enough, I had to be mindful of that flap.

I imagine the obstruction would affect high-demand acceleration.

[tobydad]

One possible problem could be the fuel filter being partially clogged and as you accelerate the increase in gas cannot make it through the filter. Always start with the simplest solution first.

[Keily]

I had the same happen to mine. Changed the coil packs and plugs, a was good after that. I had 178 km at that time, traded it shorty after that.