Just wanted to know the exact cause of Pinging. I have a 98 4.6 F150 and at high way speed (75) I get Pinging when I accelerate. I get it with 87 and 89 octane. Is this from a lean condition? Would a cold air intake help?

 

Off the top o' me pointy head:

One or more:

Bad EGR
Bad DPFE
clogged EGR ports in TB
faulty front O2's
combustion chamber deposits
wrong heat range spark plugs
bad gas
clogged fuel filter
bad PCV / PCV elbow
dirty MAF
.
.
. etc ... the usual maintenance stuff

No - a cold air won't help with this, or anything else.

good luck

EDIT: I'll page the feller whut knows this stuff cold fer yall - I'm just a Padawan



MGD

 

Thanks for the ideas. I would assume with a bad egr or dpfe or o2 sensors you good it a CEL. I have a new fuel filter. I know there are new plugs in but not sure what they are. The Pinging goes away if I put 91 octane in though. How do you clean the combustion chamber with the heads on?

 

Dealer - Motorvac cleaning process.

Don't use Seafoam - it won't work.

Aging/lazy front O2's won't necessarily set a code. If they are original and you have over 100K miles they are past due for replacement anyway.

Hopefully 'Brewsky will drop in and offer his vast insight.

good luck

MGD

 

Are you opening your door up at speed??

jk

 

This is my beater truck so anything with the dealer will not happen. I am not sure how many owners this truck has had but O2 sensors may have been on here for awhile. The truck has 140k on it.

 

Had the same truck with the same engine doing the same thing. Just ran 91 in it and it seemed to do fine. Gave it to our daughter and son in law at 255 k still running ok otherwise.

 

I can do that just do not want to cause 91 octane is 30 cents more expensive and that adds up when the gas tank is big on these trucks.

 

Pinging is detonation which can be caused by to much timing for the octane of fuel or lean conditions or oil vapors in the combustion chamber(PCV system stuck open). Open lowers octane ratings if fuel.

Try running a higher grade octane, lowering timing and/or making sure you aren't getting any type of oil in the intake.

Wayne