engine pinging

[keithsranger]

99 Ranger 4x4, AT, 3.0 liter, flex fuel pinging when accelerating, especially climbing hills. Using 93 octane stopped the problem for a while, but it has returned (intermittent). Appreciate any ideas? Also does this engine have an anti-knock sensor?

Thanks!

 

[RonD]

No knock sensor on your '99 3.0l

Pinging/knocking is from the fuel/air mix igniting from compression and heat just prior to the spark plug igniting it, the noise is from the two separate "explosions" meeting in the cylinder.

Pinging generates extra heat so once it starts it will continue until load(fuel) is reduced.

Pinging can start if fuel/air is too lean, richer mix is cooler, O2 sensor issue, but a long shot

EGR valve/tube can get carbon build up which lessen the amount of exhaust gas being feed into the intake when valve is opened.
Exhaust gas "cools" the fuel/air mix, as odd as that sounds, lol.
So EGR must be clear of any build up.

Timing can be too far advanced, but on a '99 I don't think you can adjust it, just check it.
The Cam Syncro sets injector timing and I believe some spark timing under load.

Carbon build up in the cylinder increases compression so heats up fuel/air more.
Just check the spark plugs for signs of carbon, black residue.

I would start with the EGR system, remove valve and look at it and in the tube.


Octane is a heat rating, the higher the octane number the higher the temp it can withstand before self ignition will occur, but all fuel will self ignite if temp gets high enough

 

[Road Angels]

check for codes for dpfe sensor for egr

 

[keithsranger]

Thanks RonD & RoadAngels! Some good info! I'll post what I find out.

Thanks again!

 

[straycat]

Run a bottle of fuel injector/cleaner in the tank. When was the last time the fuel filter was replaced and did you do a fuel system cleaning?

 

[keithsranger]

Thanks, ill try all of the above probably starting with the cheapest. And straycat, i dont have the slightest clue, probably need to look into that. Thanks again. I was told to check the MAF just to be sure and it seems to be working the way it should, no problems there, but hopefully yalls input will be solution. Any other help is much appreciated.

 

[Earl43P]

Unplug the vacuum line from the EGR valve and drive it a few days like that.
Should light the CEL eventually and quit pinging.
If so, replace the DPFE.

Mine has done that at least 3x.

 

[keithsranger]

Thanks Earl43P. Ill do that. The noise is just so aggravatin. Hopefully this will solve the problem! When did you notice the pinging noise the most?

 

[Earl43P]

Going a steady speed, it would ping as soon as I would depress the gas to accelerate or climb a hill, as if I were in too high of a gear (but wasn't).

I tried all kinds of fixes, a 180 Tstat (gave it more power, but less mpg and had to clean the IAC regularly), higher octane gas (bandaid), got rid of the K&N filter, cleaned the MAF, etc.

Mine eventually started trailer-hitching / bucking at light throttle, steady speed. THEN the CEL finally lit (months later) with P0401.

Now, as soon as it starts bucking at steady speeds, I buy a new DPFE, every other year or so. I attribute my failures to moisture from all my short trips (4 miles, 4X, EVERY DAY)

 

[keithsranger]

Sounds like we have the same symptoms and the same problem (or did) ill unplug that vacuum line and see what happens, hopefully the outcome will solve my problem as yours did. Tried the 93 gas and solved it for a little bit, but came back and and cleaned the MAF also but it did no good. Where is the EGR valve vacuum line at?

 

[Earl43P]

I don't have a good photo, but look for it attached to the intake manifold. Plug the elbow with a golf tee or something (vacuum leak).

See here: http://www.tomco-inc.com/Tech_Tips/ttt33.pdf

http://www.tomco-inc.com/Tech_Tips/ttt35.pdf

 

[keithsranger]

Alright thanks! I appreciate the info, ill give it a try and ill let ya know how it turns out or if i have any questions, thanks again.

 

[cp2295]

Check out tsb 00-24-08. You might need to change the coil pack and get the PCM red lashed. Try decarbonizing with seafoam, 1/3 pint in the vacuum lines with engine running.. Do it slowly and have a helper keep the engine Alive with the throttle. 1/3 in the fuel, and 1/3 in the crankcase and change the oil after 75-150 miles. Egr is definitely a good suggestion.

Look at a vacuum gauge and see if you have an intake leak causing a lean mixture.

 

[Froggmann]

I went through the pinging issue with my truck right after I bought it. Tried a couple cans of seafoam, multiple bottles of fuel injector cleaner, new DPFE, etc--nothing cured it.

Running a couple tanks of E-85 through it completely transformed how the engine ran. Smoother idle, more power and no more pinging. Best fuel injector cleaner/decarbonizer on the planet, bar none.

 

[RonD]

I went through the pinging issue with my truck right after I bought it. Tried a couple cans of seafoam, multiple bottles of fuel injector cleaner, new DPFE, etc--nothing cured it.

Running a couple tanks of E-85 through it completely transformed how the engine ran. Smoother idle, more power and no more pinging. Best fuel injector cleaner/decarbonizer on the planet, bar none.

Yes, if you have the Flex Fuel option the E85 will clean out the carbon in the cylinders and stop the pinging when using gasoline, if that was the cause.