I have a 4.6L ,what would cause it to ping under load ???

 

to low a grade of gas,too hot a plug,engine running to high water temperature,maf sensor dirty,computer needing recalibration for type of driving your doing....any others?

 

general need of a tune up...wires, plugs. Too much timing. Ummm....Sometimes you get it on tipin.

Seabass

 

the number one reason for that year engine is a dirty EGR system (Not just the valve)

have you been using a higher octane gas than your owners manual calls for? If you have you probably have a bad carbon build up in the cylinders.

find a shop that has either a BG or Snap On carbon depletion machine.

my .02

 

Mine started to ping very slightly under a load, 2 sleds on a trailer
this was at about 90,000 km.
Changed the plugs,twice. dealer said only to use oem, didn't help.
Just kept getting worse. check eng light wasn't on. Changed the
egr valve, cleaned out the egr pipe,replaced both upstream 02
sensors. All other maintence items fuel filt,pcv,air filt,had injector flush at dealer. Dealer said they couldn't do anything until light came on. Tried octane boost,use injector cleaner regularly.
Ping is only noticable at high rpm (passing) or loded heavy(trlr).
It is worse on hot dry days,not as bad on cool days, air density?
Now at 130,000k the check eng light is on but still runs fine.

 

Forgot to mention 97 f150 4.6l. 95% highway miles

 

I'd say it could be due to a dirty MAF element. That platinum can get dirty very easily, especially if you're running a K&N filter. Clean it off very carefully with a q-tip.

-Flea

 

MY 97 4.6 would ping badly and run sort of rough on 87 octane under mostly just cold weather conditions say under 50-60 degrees. Running 89 octance helped but never solved it. Cleaning the MAF and replacing the PCV valve never solved it but it did help. I then had a wierd miss on light throttle accel at 40-50 mph and 1000-1500 RPMS and then it got worse and happend at 65-70mph and 2k RPMs that I thought was the TC or trans acting up.
I think running the higher test gas did cause a little more excessive carbon build up as I started having EGR flow problems.
I tired using a little coating safe TB cleaner but it didn't remove everything. I then had to remove the TB elbow and clean the two EGR passageways that were almost completly cogged. I replaced the EGR valve vs cleaning the old one and had to put on a new $75 DPFE sensor (might have killed it with the TB cleaner, only getting 2.8v reading).
I then just recently had the plugs changed (40K on old ones) and the miss is gone, idle is better, truck is running better, and I would bet the pinging is gone even running on Marathon 87 octane. The temps have been way to high to see if it does it only when cold still but it did improve.

My correction to a pinging problem thats has had results for me would be:
change plugs, maybe the wires on a truck without COP
new PCV valve
completly clean TB and elbow (easier to do with it removed when DIY, dealer may be able to do a better job when installed using the injector cleaning service)
clean MAF with q-tip and windex
find some way to clean DPFE
clean EGR valve
use a quality gas

 

If I remember right, pre-ignition pinging is a chronic problem with the 4.6L.

My truck started to ping under a load about 3-4 months ago. I just ignored it, considering quite a few people where complaining about pinging long before 100k miles, and it has recently quit pinging. I made no changes in the way I drive or what I do with the truck.

It's up to you, but this is the cheap way out. Minor pre-ignition pinging isn't going to do any damage. I probably wouldn't hurt to perform some of the maint. described in previous posts if you haven't been keeping up with it

 

run high oct.,76000 miles towed daugthers car to college in lubbuck from dallas lots of canyons on 114 and no pings,could be the MSD coils or the plugs(bosch plats) no maintenance on EGR system so far run K&N on moded air box(1 inch paddle bit honeycombing filter box) and chip...check your fuel filter or fuel pressure maybe to lean of delivery because of pressure???

 

I have a 97 F-150 with the 4.6 and about 75K miles. At about 60K I installed the Hypertech Power Programmer III. Around town it was fine, but under load (pulling my 6500 lb trailer) it would ping badly. I de-installed the Hypertech programming and the ping went away.

 

I believe that the owners manual says that pre-ignition noise is normal. I had a '00 Ranger that would ping when strained (up hill, passing). If my F150 had pre-ignition I would find a way to stop it. I don't care what the owners manual says, I don't think it's normal.

There are lots of great suggestions here. I would say keep up with the maintainance and use quality gas. Unless you have mods that require it I think thet using higher octaine gas is a waste of money.

I think it must be the automatics that are more prone to pinging. I've never had any problem in any vehicle with a manual trans.

 

I've had the same problem with my 5.4L SuperCrew since I had it at 16,000 miles. It wasn't too noticable until I put on a K&N FIPK, JBA headers and Borla Exhaust. There was no change in the characteristics of the noise when I added the SuperChip with 92 Octane.

It sounds to me like a zip-tie hitting a fan but there is no damn zip-tie to be found! The sound is accentuated on the driver's side. Mine is constant but worse when cruising and lifting/pressing on the accelerator that doesn't require a downshift in the transmission. It's also worse on hot days.

I've taken it to the dealer who replaced the the EGR tube and valve asy, Cat Converter, Exhaust gasket to end up with NO resolve in the problem. They ended up saying that "some exhaust type noise is normal." I still don't think it's normal.

 

One thing I have realzed is that the valvetrain noise that these Triton engines make is not all that far off from the sound of pre-ignition. When I put the blower on I listened so intently to the engine, fearing pre-ignition. I thought I could hear it. Then I realized that it was indeede the valvetrain noise. I could tell especially when I was going by a guard rail or Jersey barrier. I also drive an E250 5.4 for work and it makes the same noise. I paid closer attention to what the other Fords with the Triton engine sounded like. They all have the same noise.
I'm confident that I'm ok. I don't know if this might have something to do with some of you that hear pinging. I'm not saying that you are wrong or to let it go but that this is what I have found.

Good luck!