2004 4.0 auto 30,000 miles hearing pinging(detonation) usually uphill with or without ac on. tried different gas grades no effect. No check engine light no codes bein thrown out. Truck runs well avg. gas mileage. but still pings--dealer has no answer--------lookin for items to check.


thanks madmike

 

one thing... check your coolent... there was a problem with f-150 back in the day where there was to HIGH of a content in antifreeze... thus not alowing the motor to cool properly and the heads where to hot and cause pinging.. simply changing the coolent with the right mixture fixed it... just and idea

 

probably coolant. But I've also heard that changing out the Thermostat is also a great way to fix it. I think I remember reading that a 180 degree thermostat sends in the coolant more often and thus the engine stops all pinging. Im not 100% sure if thats right though

 

Do you keep the oil changed regularly and all? Usually that's a fairly easy thing for the dealer to find permitting you give them a good description. I've also seen a spark plug/plug wire problem under a load cause a problem that doesn't set a light or a misfire. If you're having a pinging problem and want to see if it's coolant related go up a hill when the engine temperature is low.

 

Alright crew tried the coolant issue--67cobain94 oil is changed every 3000 miles mostly all highway miles-pinging is noticed when temp is @ normal operating temp. gauge is hovering in middle. also seems @ its worst around 2000 to 2500 rpm uphill--could be plugs or wires will continue checks--does anyone know what factory plug wires should read ohmically (ohm meter)???????

 

so your saying it only pings when warmed up? change coolent to the right mixture for your area

 

Tell you dealership to look up the TSB regarding PCM reflash for your truck. I had a ping when my engine was under load (in my case going uphill) and running the AC.

post for reference....

https://www.ranger-forums.com/forum2...ad.php?t=24971

 

mine does same thing except more of a bucking than a ping- dealer totally useless( he said it didn't do it for him so i guess its fixed????? what bs)..my friend that is a mechanic was in it when it did thinks it an ignition misfire...ordered a coil/ wires from wayne and then getting new plugs- also doing an used oil analysis

 

If it's truely a "ping".. that is a flame front that's hitting the piston face too soon.. it's called detonation. You have to reduce timing, increase octane, or speed up the piston. One of the three.. or some balance of the three will solve the issue.

I suspect that if you ran a *full tank* of 93 octane and are still seeing this.. your not actually detonating.

Some other things that sound similar.. loose spark plug, exhaust leak, an excessively loud injector, or a bent valve.

Rich