I posted last week about the mild pinging that my 2004 Heritage 4.6L was experiencing at cruising speeds. I pulled the throttle body like many suggested and saw the clogged EGR ports like everyone else. I cleaned those, reste the ecu but still experienced the pinging. Well, I took it back in to the dealership on Thursday and spoke with the service director. They hooked some machine up to the fuel rails, disabled the fuelpump and ran it off of this machine. According to the manager, after a few minutes they change the catalyst they are injecting to some sort of foaming agent, allow the truck to stall and let it sit for a few hours. I got it back on Saturday and havent heard a ping out of it since! I am thrilled with the results. It idles better and runs much smoother as well. I'm sure some of you mechanics know the details of what they used alot better than I can recount it here so feel free to explain...

 

Did they say what the "foaming agent" was? Sounds like sea foam which is used to clean fuel systems and internals.

 

No, I am familiar with seafoam and have actually used it on many occasions myself. This does sound like the same concept but on a much more thorough basis. They said this was some sort of machine they have that actually runs the truck through the valve on fuel-rails instead of by the gas in the tank. They run it for some time to clean the injectors and then hit a button that foams the engine and stalls it. They let that sit for quite a long time. Whatever it was, it worked.

 

Sounds like "motor vac" it costs $100 at the dealer here in canada