low RPM ping at normal engine temp

[jorton]

The search feature doesn't seem to be working b/c no ping or detonation topics showed up on pg 1.

My 99 f150 v6 auto transmission has some ping or detonation when at low RPM and slow speeds. The engine may actually be lugging but I can't help that b/c the truck shifts up to a higher gear automatically.

Here's the advice I found at a site dedicated to Ford trucks:
get used to it
change to 1 step colder spark plug
change to 89 or 92 octane gas

Before I do anything I would like some more tips from folks who are familiar with this condition. Thanks, Joe

 

[surfstar]

Try to decarb the engine with water or seafoam/etc. Carbon buildup can cause pinging in some engines.

 

[punisher]

Add to the list:

Check at the dealership to see if any upgraded calibrations have been released by FoMoCo. We got new calibrations all the time for problems like pinging etc.

As mentioned above, check the MAF sensor. If you know someone with a scan tool, verify fuel trims on light load/cruise conditions.

Might want to give your vac lines/fittings a once over to look for a very small leak (unlikely, but for peace of mind). I would suggest checking EGR ports/valve actuation but chances are an OBDII system will catch an EGR problem before you will notice it while driving.

 

[Whimsey]

You might want to look at CAREFULLY cleaning the MAF sensor. I have a 2002 F-150 with the 4.6 V-8 and it has begun pinging at light throttle. It's a manual tranny and I don't lug the engine in the least bit. There are no codes stored in the computer. In fact it even pings with high test fuel, but less than with regular fuel. I only have around 27,000 miles on it. But the miles are mostly highway miles. When it warms up here in NJ I'll look at cleaning the MAF sensor.

Whimsey

 

[jorton]

punisher - thanks for the professional advice! When I go to the dealer for updated calibrations I don't want to pay for other things I don't need. What exactly do I say to the advisor so that he knows what I want?

 

[GenesToy]

jorton get your vin number and call the service advisor and ask him to check and see if their are any service bulletins out for pinging or computer program updates for your vehicle. Be sure maf sensor is clean at the fine wires will cause ping and loss of power making it run to lean at certain rpm.

 

[mechtech]

Cold plugs won't do jack for your problem.
Going up a grade in fuel will help.

 

[jorton]

My engine model has a history of clogged EGR ports.

I can see the insulated pipe that goes to the EGR. Is there also a line that goes to the intake I can't see? How many ports does an EGR have, and how do I clean them? With a brush from a gun cleaning kit?