Sounds like marbles in motor when I accelerate

[roDeo2000]

Is this something serious or is it bad gasoline. When I accelerate it sounds like a bunch of marbles are pinging around and it stops when I let off the gas pedal?? I don't know much about cars, only basic stuff. I also changed the gas cap because the check engine light came on recently and I have been having trouble with the gas gauge being off. The check engine light goes on and off sometimes. Confused!

[2eyefishclaw]

first check your spark plugs many of these came with champions they do not work very well switch to nippendenso also fuel grade can be a big issue use 87 octane that is what they are designed to burn

[blackshine007]

It could be the timing belt tensioner that's starting to go out. Soon after a while it will be constant and will here it all the time. Or it could just be the grade of gas that you put in

[2eyefishclaw]

pinging noise is spark knock not a noisy t-belt tensioner

[Cat Fuzz]

Originally Posted by 2eyefishclaw

pinging noise is spark knock not a noisy t-belt tensioner

If the timing belt tensioner is going bad, that can vary the valve timing and cause knocking.

[2eyefishclaw]

I do understand the concept of valve timing the thing is that I work on stricly Isuzu 5 days a week I am very familiar with them and I know that if the description given is correct then the concern is not going to be a timing belt concern or tensioner concern. I know enough to say that when these tensioners give there is usually a knocking noise that most people misdiagnose as a lower end engine knock or a water pump gone bad. Getting back to the concern yes it is definatly a timing concern usually induced by the cust running improper fuel or 93 octane these vehicle are not set up to run on that stuff 87 is what should be used. There is also a calibration update for the PCM that may also help to reduce this. I have even seen where people replace the original plugs with BOSH platinum Junk which will also cause this. These engines really like NIPPENDENSO but will also work with NGK

[Cat Fuzz]

Originally Posted by 2eyefishclaw

I do understand the concept of valve timing the thing is that I work on stricly Isuzu 5 days a week I am very familiar with them and I know that if the description given is correct then the concern is not going to be a timing belt concern or tensioner concern. I know enough to say that when these tensioners give there is usually a knocking noise that most people misdiagnose as a lower end engine knock or a water pump gone bad. Getting back to the concern yes it is definatly a timing concern usually induced by the cust running improper fuel or 93 octane these vehicle are not set up to run on that stuff 87 is what should be used. There is also a calibration update for the PCM that may also help to reduce this. I have even seen where people replace the original plugs with BOSH platinum Junk which will also cause this. These engines really like NIPPENDENSO but will also work with NGK

Hmm, I put Autolites in every vehicle I own and the Rodeo seems to run fine with 'em. It does hesitate on acceleration, but it did that before I replaced the plugs. I have no trouble codes in the computer, so I'm clueless.

[surferfletch]

I just finished reading a spark plug thread on the VW site, and the consensus seems to be against the Bosch product, too. Most say NGK or nippondenso, and some suggest the cheap Autolites. I have the Autolites in the Jetta and they work just as well as the Bosch. I'll probably go with Autolites in the Rodeo, too.
More on topic, I've never experienced the kind of pinging described and I run only 87 octane. Good luck and update!

[2eyefishclaw]

I have never known anyone to try the autolite plugs before if they work for you then great they are a little less expensive
I just like using what they come with

[Cat Fuzz]

I really don't understand how one spark plug can be better than another. All they are is a wire and electrode packaged in a container designed to fit into an engine. Resistance is not an issue since the spark plug circuit is so short there is virtually none anyway. Splitfire and other such plugs are just gimmicks that do nothing. The only superior product I can see is platinum tipped electrode which only extend the life of the plug by resisting electrode wear. I've been tweaking and messing with cars for almost 20 years and have never seen any evidence that any standard brand of spark plug is better than any other. I'll stick with the Autolites.

[rodeo02]

Fuzz- You might get your pre 1998 isuzu to run fine on autolites, but you definately wont on 1998+ 3.2/3.5's. These engines have a direct ignition system (coils directly on top of the spark plugs), pretty much any plug other than a denso or NGK causes the PCM/ECM to pickup random misfires. From what I understand it's caused by the radio interferance given off by such plugs. Year 2000 & up are even more sensitive to plug type. These engines have the GM/delphi "ion sensing" ignition system where the spark plugs are used as a sensor (when they are not firing) to measure the electrical resistance of the gasses in the combustion chamber. This system is designed around denso, NGK plugs. Again, anything other than denso or NGK in 2000+ causes MAJOR problems. I've seen reports of this OVER and over again. I too have been messing with cars for over 20yrs. If you want a plug that's going to last in a Japanese/Asian engine, use NGK's or Denso's in them. Older American iron can run on just about anything.

G/luck
Joel

[surferfletch]

Maybe I won't put the Autolites in the Rodeo (my '97 has direct ignition, too!).

[paulsantangelo]

I saw this on the web, perhaps it might help!


Detonation is a condition that exists in the combustion chamber when the fuel/air charge or mixture is ignited by something other then the spark of the spark plug. This can be cause by hot spots in the combustion chamber like carbon that is glowing red and igniting the mixture. It can be caused by excessive compression like in diesel engines that generate so much heat the mixture just lights off. Forcing lots of air into the engine with a supercharger can also lead to detonation. I am sure there is dozens of other things that can cause detonation, but the important thing to remember here is that detonation is when the mixture is ignited by something other then the spark of the spark plug.

Spark knock is when the spark of the spark plug ignites the fuel/air charge in the combustion chamber sooner then is should. If the ignition is to far advanced it can lead to spark knock and you can hear the engine rattling like marbles in a coffee can. There are things that can contribute to this like a lean mixture, a faulty EGR system and probably a bunch of other things. Again the important thing to remember here is the mixture is lit by the spark of the spark plug, but just to soon.

[boostedwrx]

maybe problem could be more then all these "spark plugs" posts...anyone ever think that a lifter or all of the lifters are broken?

[surferfletch]

Any update?