1999 Mazda B2500 ENGING PINGING PROBLEM!!!....HELP PLEASE&

[Mazdaboi182]

Hi there,

I have a 1999 mazda b2500 truck with the 2.5L inline 4-cyl. My truck only has just barely under 111,000 miles on it. I am having some serious PINGING PROBLEM with it. IT IS DRIVING ME CRAZY. Ok, well i have taken it to a mazda dealer and they told me that replacing the catalitic converter because they said that the interior of it was cracked and broken. They said that this should cure my problem. So i went ahead and replaced it, but it didn't cure my engine pinging. I just got screwed! So then about a week later i take it into the Ford deal and they said oh that they could do an "octane adjust" which it turned out that they could not do this because apparently there is not a setting in my ECU for that and they couldn't further help try and figure out what is the cause of my pinging problem.

So far, i have replaced the catalitic converter, installed new O2 sensors, checked the spark plugs and the gap and they were fine, checked the spark plug wires (good), checked the air filter (good), and even done the sea foam carbon engine cleaner thing... pretty much done as much checking and maintenence that i could think of.

It pings the most when the engine is all warmed up but i can still get it to ping when it is really cold out. If i put in the high grade gas it helps but still pings OR if i put in 2 bottles of octane booster one (bottle is suppose to treat up to 16 gal.) it again helps it from pinging really bad but still pings. I have noticed that the warmer the OAT (outside air temp) is the worse my pinging problem is. I dont have to press very hard on the accelerator to get it to ping. The times that it pings the hardest (sounding almost like a diesel truck at times) is when i go up hills, lug it, when the engine actually has to pull the weight of the truck, accelerating of any kind, or even driving on a level freeway. I have a hard time doing the speed limit of 60mph and trying to keep the engine from pinging.

A mechanic that i know has one of the computers that you plug into a cars computer and he did it to my truck the other day. His analysis of what the computer was showing him was that comparing the short term and long term fuel % or whatever that is... he said that my truck is running very rich and it keeps trying to lean itself out and apparently it isn't really doing that. I am not really sure what that is suppose to mean other than the fact that the engine is getting more fuel than air in the fuel/air mixture. He also mentioned to me that it could be possible that my timing belt could be stretched out, got warm and could have jumped a tooth on the timing gear thus throwing my timing slightly off and causing the pinging. I dont know, does this sound like it is reasonable and is it a common problem?

Also, i have heard that on my truck there isn't a way to change the timing because it is all controlled by the computer so is this true?

SOOO....DO YOU HAVE A CLUE WHAT MY PROBLEM COULD BE???

I am absolutly clueless as to what the heck is causing my truck to ping and i would like to get it fixed soon because i am planning on doing to cross country driving this summer. If anyone could please give me some input OR direct me on this problem, OR if your have some other idea's on what could be causing it to ping, OR you have any questions for me in helping me solve my engine pinging problem I WOULD GREATLY APPRECIATE IT!!!!

PS: sorry about the long length but i wanted to give you a good idea of exactly my whole situation for more accurate diagnosis.

THANKS FOR READING and again please send me a message if you think you could help me in anyway because i am to the point of giving up.

THANKS AGAIN!!!

[Tyranitar]

Actually, pinging is caused by running lean. I would look for a plugged injector. A plugged injector will cause one cylinder to run lean, and the others to run rich. I would also look to a plugged fuel filter, a faulty fuel pressure regulator, or weak fuel pump.

[Karl411]

I have a 2000 B2500 and have the same pinging problem. I found the problem started less than a year after buying and think I know what causes it. I visit VA. and NC once a year and when I fill up there I dont have the pinging problem and probably because they dont have Ethanol in thier gas. NY has Ethanol and I ping constantly here but when I visit NC and VA I find the ping is gone. I dont see any other reason for the pinging besides the rotten Ethanol. Why else would the pinging disappear when I fill up with ethanol free gas in those states?
Lets all thank the rotten politicians who force us to put food in our gas tank thus raising the cost of corn and corn products and giving us problems with our engines. What a mindless bunch of evil men who rule us.

[Tyranitar]

Ethanol is actually an excellent octane booster. I doubt it causes your pinging.

Again I repeat, pinging is most often caused by running lean. Check your Long Term Fuel Trim. This value requires a scanner to read. It will tell how much the computer has to adjust the mixture off factory values. If the LTFT is not within ± 5%, ideally with ± 3%, then you have a fuel management problem. Positive values means the computer is detecting a lean condition and attempting to add fuel to compensate. Possible causes include: vacuum leaks, intake leaks, dirty or defective MAF sensor, fouled oxygen sensors, misfires, incomplete combustion, faulty PCV valve, etc.

These vehicles are old enough that the vacuum lines can deteriorate. They are also old enough that the intake manifold gaskets, both upper and lower, can shrink and crack, also introducing leaks. This is very common, possibly the most common cause for pinging. There are test to check for leaks, but in order to perform them accurately, you need a scantool. A better approach is to simply check the condition of the hoses, especially around elbows. The PCV elbow is a common leak site.

Another common problem area is incorrect ignition components. All to often people think that because they have replaced the spark plugs that they are good and that the new plugs could not be part of the problem. These engines are very picky about the quality of the ignition components. The only brands that work well in these trucks are Motorcraft, Autolite, and in some cases, NGK. They have to be the correct gap and heat range, they must be double platinum or better, and they must have a single tip and electrode. Parts from other brands often create pinging because the heat range and displacement of the plugs is wrong, or parts of the plugs get too hot.

The MAF sensor can read incorrectly if it gets crud on the element. This can happen to any MAF, but is more likely to happen if you are using certain kinds of air filters, namely oiled filter elements. They are also more likely to get contaminated if you do not replace the air filter on a regular basis. There are specialized cleaners that you can try spraying on the element to see if that doesn't help. The MAF can be tested as well, not sure on the procedure.

It is possible that carbon deposits can have formed over time, increasing the compression ratio, and that can result in pinging. Various tuneup shops offer services to clean these deposits from your engine. In my opinion, these are worth the investment. A cleaner motor performs better. It is not recommended to use an octane higher than the one recommended in your owners manual. If you do so, it can contribute to carbon deposits which can cause pinging, not prevent it.

Ethanol is not going to cause pinging in the short term, E85 has a rating of 105 due to the high ethanol content. E10 is rated at whatever the pump states, but the ethanol itself is a high octane fuel. Its also very good at cleaning the motor and removing deposits. Don't get me wrong, I am not a fan of ethanol, I'm just stating that your assessment of it is incorrect. For the record, Virginia and North Carolina both have Ethanol gas unless the pump specifically states otherwise. Your lack of pinging in those areas could have to do with a long drive cycle or an elevation change.

[lanechaffin]

I also have a 99 b2500 2.5/manual it has almost always pinged, at first i noticed it seemed to be worse in the winter. (i tihnk it was winter, not summer) i know they change fuel blends by seasons- but anyway i started running mid-grade year round and it doesn 't knock with that.

[Tyranitar]

Pinging is not going to get worse because of winter mix, the ethanol added to the gasoline is a good knock inhibitor.

If you run the proper octane, you should have a problem unless you have a bad sensor or other condition that causes the engine to lean out. If you get a vacuum leak, that will cause a lean condition and pinging, as will a dirty MAF sensor. Sometimes the sensor can't be cleaned and has to simply be replaced.

If the fuel filter is plugged, it can cause a lack of power and pinging, as can a weak pump. A plugged injector as I sated earlier will cause a lean condition on that cylinder, but can cause a rich condition in the other cylinders.

If you run the wrong plugs, you can have problems, there are only three brands that work correctly on these trucks, Autolite double platinum or better, Motorcraft, and NGK double platinum or better. If you put on other brands, it is not uncommon to have pinging, misfires, rapid wear and failure of the plugs, fried coils, etc.