Community Forums

knightstorm · 06-08-2019, 05:30 PM

2017 chassis, 10,000 miles.

I’m hearing engine knock (or vibration from something else) when climbing at full throttle from about 3200 - 3800 RPM.
I can stop the noise by backing off the throttle a bit or letting it downshift (to 3rd) and rev to 4000 RPM where it seems quieter.

I checked for error codes with my scanner and all it came up with is a b1352 left front temperature damper motor, which makes no sense to me at all.

Any ideas?

jackreno · 06-08-2019, 09:07 PM

I had a pinging issues twice with my 08 Bounder F-53 chassis, once it was bad gas and the other time it was a fuel filter plugging up, might want to replace the fuel filter 1st and see if it goes away..

twinboat · 06-08-2019, 10:32 PM

Doesn't it downshift automaticly, at full throttle, and rev over 4000 RPMs ?

At 3200 RPMs and full throttle, your lugging that engine.

knightstorm · 06-09-2019, 04:45 AM

I can avoid the noise by turning off cruise control and backing off the throttle or forcing a downshift with the throttle, although there have been a few times where I wanted a 4-3 downshift and the transmission control wouldn’t cooperate. I need to display the gear commanded as well as the current gear to get a better idea of what’s going on then.

twinboat · 06-09-2019, 06:14 AM

You may want to get Ford to check the programming of the computer.

My 2017 climbs hills, in cruise control, downshifting and up shifting as needed to hold its speed.

I just came up I 81 thru PA and NY and never needed to work the throttle.

vettenuts · 06-09-2019, 06:55 AM

I would also clean the MAF. A dirty MAF will lean out the fuel and cause a lot of issues. Usually the computer will pull timing to get rid of any knocking, but this is something that should be addressed ASAP as it can cause a lot of damage.

MoCoTom · 06-09-2019, 06:21 PM

You need to find the problem and have it fixed as soon as possible because severe piston damage is a direct result of pre-ignition (pinging). If you allow the ping to continue for an extended period such as might occur on a long hill the probability of damage multiplies. Anything you can do to stop the ping such as changing throttle position or RPM would be a good thing until you can figure out what is going on

georgelesley · 06-10-2019, 05:51 AM

Are you using the tow haul feature? It will shift sooner and hold lower gear longer. We have it on all the time whenever towing. I agree, sounds like you are lugging the engine a bit. The V-10 loves revs.

knightstorm · 06-10-2019, 07:24 AM

I made it home, and only need to drive it another 100 miles or so to get it looked at. Almost half a tank of 93 octane added at my last fill-up made no difference, and it seems to pull up hills in 3rd at 4100 RPM with no problems.

I just spoke to my dealer, who has another, less critical, possible cause. The transmission dip stick could be rattling against the engine cover. That would explain why it doesn’t make the noise under full throttle in second gear and why it goes away at higher RPM.

That also goes along with my first impression that this was a vibration/rattle noise rather than engine knock. I’ve heard engine knock before and this doesn’t sound quite the same.

Years ago I had a gen 1 Dodge Durango with the big V8 that knocked. My mechanic suspected a leaking intake manifold gasket allowing oil to enter the intake air and sent me to the dealer (it was under warranty). The dealer found nothing, but several years later I ended up with a blown engine due to a failed intake manifold gasket.

theoldwizard · 06-10-2019, 05:43 PM

Quote:

Originally Posted by knightstorm

I can avoid the noise by turning off cruise control and backing off the throttle or forcing a downshift with the throttle, although there have been a few times where I wanted a 4-3 downshift and the transmission control wouldn’t cooperate. I need to display the gear commanded as well as the current gear to get a better idea of what’s going on then.

Isn't there an overdrive cancel button on the end of the gear shift stalk ? It might take 5 or 10 seconds for it to downshift from 4th to 3rd, so I always do it at the bottom a hill.

Also, if I know I am going through a hilly area, I fill up with premium, even it is is just 1/2 of a tank. Makes a difference.

Mike8253 · 06-10-2019, 08:49 PM

Quote:

Originally Posted by theoldwizard

Isn't there an overdrive cancel button on the end of the gear shift stalk ? It might take 5 or 10 seconds for it to downshift from 4th to 3rd, so I always do it at the bottom a hill.

Also, if I know I am going through a hilly area, I fill up with premium, even it is is just 1/2 of a tank. Makes a difference.

On older models, that botton on the end of the shift lever was to go into and out of OD. But on a 2017, it's for Tow/Haul.

Bobkat3080 · 06-12-2019, 02:14 PM

Our 2018 Newmar Baystar 3414 developed a rattle/ping noise at certain engine loads. I found it to be the exhaust pipe from the generator was rubbing on the engine because one of the mounts holding it in place had broken. At certain speeds the pipe/engine would vibrate against each other. The generator is in the front left bay and the pipe exits in the front left of the rig passing close to the bottom of the engine. Fixing the mount solved the noise problem.