I've got a 01' Edge w/the 3.0L automatic in it and I have had a continuous spark knock problem for some time now....I've done everything to try and stop it...new plugs, wires, fuel system cleaned out, run nothing but 89 octane gas....and I still have it. I've takin' it into a ford dealer and had them look at it....they updated the computer and told me everything seemed fine...but still, spark knock. It used to knock when I ran 87 octane and didn't when I started running 89, but now it's knocking all the time with the 89 octane as well....have no clue what to do, advice would be appreciated

 

When you say spark knock describe what you're speaking of. I can say I've heard a couple different sounds from an engine that sounded about like a knock but had different causes. One being a loose spark plug, another being detonation. If the 89 octane made it go away for some time then I'd lean towards detonation. If you tried 91 and that gets rid of it then detonation is definately the problem. I'm not sure how to cure it in a truck that new, but try calling your ford dealer and see if your motor has a knock sensor. If it does then replace it. A knock sensor on a motor tells the computer what to do for adjusting the timing to eliminate the detonation without different grades of gas. This problem isnt very uncommon in 98-02 camaros for some reason as well. The computer on the Camaros doesnt recognize the sensor as being bad.

I might be barking up the wrong tree since I dont know the ins and outs of a 3.0 that new. Someone else will chime in and probably shed a light on the subject.

 

Check the below link:

http://rogueperformance.com/pinging.html

Also, you might try putting in a cooler thermostat. jd

 

Guys w/ 3.0s on another forum swear by Seafoam to de-carbon the combustion chambers to avoid the ping.

 

I've never had a problem with carbon in my 3.0 and it's got 156k on the ticker. But it do run the bejesus out of it and I've heard that running an engine hard will blow the carbon right out of a motor.

 

Is this a "flex fuel" 3.0L ?????

 

Thanks for the reply....but when I took it to the ford dealer the first time, they told me I don't have a knock sensor, and yea, when I put a higher octane gas in it, there is a little knock, but it goes away.....in regards to if it is really spark knock....I've had atleast 4 mechanics in the truck w/me that tell me that it is.....as for the timing, the dealer upgraded the computer and said everything was fine, and no, not a flex fuel 3.0....i've seen the carbon build up before when I've taken it in to get my oil changed, and had some cleaner added...but it didn't help for long....I guess I'm lookin' for a solution that stops it entirely....thanks for the advice though

 

Ok, non flex fuel 3.0L, that eliminates one possible problem point & sounds like the Dealer has taken care of some other known problem possibilities.

You say you've had a continuous spark knock problem for some time now, which leads me to believe you've not always had the problem, right????

So, did this problem begin slowly over time, or suddenly after some event????

The fact that it responds to a octane change, suggests it's a combustion problem, rather than some engine mechanical thing, imo

What heat range Motorcraft spark plugs & thermostat, are you now using?????

Does the engine use/burn, (not leak) any oil between changes?????

Have you changed oil brands, type, viscosity, or service grade since the problem began????

Do/have, you been using "Top Tier" gasoline's, or the least costly brand available?????

On Edit: Have you changed wheel/tire diameter, or made any running gear, or exhaust system changes????

 

Pardon my ignorance, but I thought all 3.0l trucks after about 2000 were flex fuel....

 

Not true. There has never been a complete switch over to flex fuel. I think for '99-'01 a majority of 3.0L Rangers are FFV. After that, you won't find as many made per year.

Regarding the 3.0L and pinging, reference Section V in this thread. I'd also recommend the Seafoam treatment for decarbonization of the upper cylinders & intake.

 

I bought the truck in April of 05' with 27,000 on it....it didn't have the knock then....it occured over time....as for the new plugs, I know they are motorcraft but I couldn't tell u specifically what they are...I'd have to pull one out and look....the engine doesn't burn or lose any oil between oil changes...actually I'm really surprised on how good the oil looks after about 4,000 miles.....as for oil brands....I'm not sure wht the previous owner ran in it but I have used quaker state ever since I got it....the type the manual recommends for the truck.....and gas....Sunoco or Shell 89 octane...that's it....

 

Roger on the knocking coming about over time. So the CCDI, on my 99 4.0L!!!!

Why have you always used 89 octane????

Thats about the only thing so far, of the things you've listed, thats questionable.

Our owners manual calls for 87 octane & doesn't recommend we use higher octane, as our computers programming, engines valve & ignition timing, are setup to use 87 octane.

Using higher octane, which has a slower flame front, is sorta like retarding the spark.

Because of the engines valve & spark timing, the fuel s still burning when the exhaust valve begins to open.

This results in incomplete combustion in the combustion chamber & causes deposit buildup over time.

It'll also cause the exhaust valve & down stream things like the O2 sensor & cat converter to run hotter than designed.

SO, you may indeed have engine deposit problems, helping to cause your knock that developed over time.

I have Combustion Chamber Deposit Interfernce (CCDI) problems with my 99 4.0L.

Which calls for me to be constantly on gaurd about my driving habits & especially the fuel I use. This danged engine is the fussiest I've ever had, about the fuel it gets & the only one thats ever had CCDI!!!!

Seafoam is a good cleaner upper, but I don't know that I'd inget it in mass through a intake side vacuum line though.

You'll likely have to clean the plugs & change the oil afterwards, if done that way.
Same for Fords 4.0L decarb TSB, that calls for us to suck three cans of Motorcraft PM-3, through a intake side vacuum line.

I use Chevron's "Techron Concentrate Plus, at the 1oz/per gal treat rate, along with the "blow it out" high rpm part, of Fords decarb TSB.

This doesn't work as fast as direct ingestion of the PM-3 or something like Seafoam, nor does it dirty up the plugs or oil, but it gets the job done in one tank of gas.

So maybe the Techron, or a can of Seafoam in a ank of fuel, at the one oz/per gal treat rate, aalong with the blow-it-out part of the TSB during the treate tank & going back to regular use of 87 octane, would help.

I'd also look at the spark plugs heat range & make sure they're right, along with making sure the thermostat heat range is right & that the cooling system & coolant are in good shape & the coolant to water ratio is at 50%, so heat conduction in the heads are as specified.

I'd even check the fans operation, the fins on the radiator & make sure they aren't clogged with bugs or other debris, like leaves, grass. mud, a plastic bag, rodent nest, ect.

Has the Dealer done a IR temp profile on the engine, to make sure the coolant is circulating properly & the heads don't have some kind of restriction problem, that would cause them to run hotter than designed????

Seems to me you & the Dealer have picked at this pretty danged good, so far.

Just some more thoughts for pondering.

Let us know how it goes.

 

yea, i've heard that if you put anything thru your engine via the intake side vacuum line it dirties the plugs and oil.....so I don't think I want to do that....I will probably try the Techron since you can just add that to your fuel tank....but what are the procedures to follow for the tsb?? I'm not familiar with the high rpm part....while driving or while parked?? let me know

Thanks

 

Look for "how to decarbon the 4.0l" in the "Tech Info" thread, atop this forum.
The TSB is listed there.

 

Others have reported that the spark knock problem goes away if they install spark plugs one heat range colder. I would try that after you use the Seafoam.