pinging/knocking?

[MFerioli]

Hi, I have a 2000 ranger 3.0 liter flex fuel. A couple of years ago I posted here about a suspected carbon knocking problem that I thought I had fixed but now its doing it again. I went so far as to remove the heads and clean both the pistons and the heads of all carbon. After that everything seemed fine, but 5000 miles later I'm hearing the same rattling type pinging under the same conditions.

What I know is that if use 93 octane it goes away even when I load the engine (higher gear, lower speed, on a hill), but Im not sure why its doing it again. Has anyone found another solution to this? Is this a timing issue and if so how is that adjusted on the vehicle? Could the computer need to be re-mapped?

93 is expensive!

Thanks for your time,
Mike

 

[McCormack]

I bought my '00 Ranger new and it started pinging at 10,000 miles - late model Ranger 3.0's have their timing way advanced from the factory for emissions purposes, and again for emissions purposes they also run the engine really hot with a 197* degree thermostat, and once the engine carbons up a little the combustion camber gets insulted and the engine will ping.

I did the intake manifold hot-water bypass mod and I also threw a 180*t-stat in, and it took care of most of my pinging issues. I also bought a tuner and retarded my timing a degree or two and that took care of the rest of the pinging.

So install a 180* t-stat in your engine and see what that does for you.

 

[MFerioli]

Thats great information, thanks a lot for the reply. I'll definitely try the thermostat first as that seem like the easiest one. Is a tuner expensive? Also, where can i find info on the hot-water bypass?

Thanks again, mike

 

[McCormack]

I think I paid $275 for my tuner a couple of year ago, and do a search here on the site for the hot water bypass mod... there's two little hoses on top of the intake manifold that feed hot coolant from the cooling system to the manifold, and plugging those hoses prevents the hot coolant from heating up the manifold, which makes for a cooler manifold, which means the intake charge will be cooler, which means the combustion chamber will be cooler, which means there theoretically should be less pinging.

 

[stmitch]

Since your truck is flex fuel, I'd suggest you run some e-85 through the tank periodically if you can find some around you. It's the best decarbonizer going, and is usually around 105 octane which greatly reduces the likelihood of detonation.
Just make sure that you ease the truck into the e-85 over time. Start with maybe 1/4 tank of e-85 and 3/4 of regular gasoline. Then step it up to 1/2 and 1/2. Keep stepping it up until you can run a full tank through. You'll be amazed at how much better it'll run!

 

[MFerioli]

Thanks guys, this is all great information. I'll definitely post back after I make the mods and let you know if I have any success. I'll also search for some e-85 and start light like you said.

Thanks again and have a great memorial day weekend!