Pinging problems--tried almost everything

[Redmanff]

I have a 1992 explorer that has very bad pinging under any load and at wide open throttle. I just had the heads replaced about a year ago and that is when my pinging started. I have also done quite a bit to try and remedy the problem. I run 87 octane cuz that is what it was made to run on! New plugs and wires (splitfire), K&N filter, hypertech performance chip, new fuel filter, fuel pressure regulator, new O2 sensor, cleaned the MAF sensor. I have also removed the octane shorting block and it helped but it is still bad. Higher octane fuel helps but it shouldnt need it. I am desperate for any ideas or suggestions that may help. I am getting very frustrated over it. Thanks

 

[SteveVB]

Your chip?

I would reinstall the factory chip and then run the codes, see if it may be the Hypertech chip. Check vacuum lines, and the intake manifold for leaks. You said you cleaned the maf, does it check out ok otherwise? Are you getting any codes?

 

[Redmanff]

Re: Your chip?

I will take the chip out and see if that makes a diff. Also I am getting no codes from the computer and the intake and vaccum lines seem ok.

 

[tbomb]

my 91 had a pinging problem. i switched to 89 octane gas and when i changed the oil, every time i would add some STP Oil Treatment to the oil. this helped a ton. the STP stuff comes in a little blue bottle, and cost about 4-5 bucks, if i remember correctly - i got rid of the 91 about 3 years ago when i got my 98.

hope this helps.

 

[mrboyle]

Did you have the origional heads rebuilt, or were they exchanged for another set of rebuilts? If they were exchanged you may want to have the serial numbers checked to verify that they are the correct heads for your model year X. If they are later model heads the combustion chamber is different (smaller) than your origional heads which will affect your compression ratio (raise it). If this is the case the pinging is due to the high compression and anything short of replacing the heads for the correct ones will do nothing to solve the problem. You could try running 92 octane fuel and see if it helps, but if they installed the later model heads it may not be enough.

 

[JoeC5]

I agree with the others. Try removing the chip. Oh yeah, you should put the octane shorting block back in. Removing that hurts your performance seriously.

 

[timfretwell]

I have a 94XLT, and had the very same problem. Like you, I didn't want to use higher octane fuel because, well, the manual says the engine is meant to run on 87 octane, and assuming nothing is "wrong" with the engine this should be all it needs. Well, I finally got over that and accepted the fact that the only way it would right was with 89 octane, even though it shouldn't be necessarry. File this one, and many others, under the heading of "Domestic Crap".

 

[rockylaurence]

I tried it all also

I even ran cleaner directly into the intake with no luck. Finally, after an oil change, I dropped two bottles of Valvoline Fuel System Cleaner into a 1/4 tank of gas. I guess the higher concentration (8x's the dose) did the job--the Ping was gone. I did try multiple brands of cleaners with no luck (following their direction).

 

[Dharris]

Had the same problem. Through some searching I found that there is a small electrical plug that Ford Technicians call an Octane Rod (carry over from mechanical advance distributors) that when removed changes the octane requirements probably by changing the advance curve. Ford did this because the Explorer is used in so many countries with poor grade fuels. It is illegal for Ford techs to remove it themselves and some will not even acknowlege that it exists. On the 92 it is a small gray plug that has two wires running into a loose socket the just hangs in the engine compartment on the passenger side in the back corner towards the firewall. I did some acceleration tests with the plug and without and could not see any difference at all. My mileage was also unaffected. In general, the way most of us drive daily there will be no drivability change except you will not hear a ping anymore. I did this 3 years ago and have had no issues.

 

[timfretwell]

Did you ever fix that ping problem? I still have the same problem and need some advice.

 

[Raceit]

An Octane Rod?

Does anybody have any more information on this?

Pictures, diagrams?