Why is my car pinging!? grr

[RiCeBuRnErGiRl]

I was just wondering if any one had any idea as to why my car would be pinging. Its a 95 and only has 78k miles on it. I went through this pinging thing once before and it was giving me the check engine light but i had the codes read and they cleared them out and cleaned out the air filter and it quit, and now its doing it again. I know your wondering "are you using cheap gas?" I had always been using 93 but here recently with the gas prices like they are ive been trying to trick her by putting in regular with octane boost. Could that be it? It ran fine for a while like that and now its pinging sooo i unnooo.?

 

[JJ95GTID]

Clean the MAF and IAT sensors first. Then check the timing. 10* is the stock setting and should be good for 87octane fuel. 12*+ most likely will need to run higher octane fuel. Octane boosters vary and some are better than others. Do a search on them and you will learn plenty. I am a firm believer in using good 87 octane fuel over cheap 93 octane fuel. For instance: 93octane fuel at the Albertson's/Circle K/etc. gas station will not be as good of quality as Chevron/Texaco/Shell 87octane fuel.
If you have the CEL on again post up the codes. Could be the ECT sensor or HO2 sensors. All effect the air/fuel mixture and can cause pinging.

 

[mo_dingo]

Well running anything higher than 87 will help stop pinging. So that could definately be it.

But running higher than 87 kills performance, so does octane booster.

You need to start with the basics. Clean your MAF & IAT, test your ECT sensor, replace your plugs/wires/cap/rotor if they haven't been, or look to be in bad condition.

Also check your fuel pressure and vacuum. A vac leak could do it as well.

But the most important part is cleaning your MAF. It's the golden rule for our cars.
Scott

 

[FORCED2DV8]

Double check your timing, if the pinging comes and goes maybe its where you get your gas, each refinery puts different additives in there fuel. I alawys use amaco or BP fuels, they are clear in color , if you look at some of the others they are yellow. check spark plugs and ignition stuff also, if that is weak it could give you those prblems as well.

 

[RiCeBuRnErGiRl]

i always get my gas at BP and my friend is supposed to be checking my timing for me... thanks a bunch ill let ya know if it fixes it or not

 

[titaniumsc03]

Well running anything higher than 87 will help stop pinging. So that could definately be it.

But running higher than 87 kills performance, so does octane booster.

You need to start with the basics. Clean your MAF & IAT, test your ECT sensor, replace your plugs/wires/cap/rotor if they haven't been, or look to be in bad condition.

Also check your fuel pressure and vacuum. A vac leak could do it as well.

But the most important part is cleaning your MAF. It's the golden rule for our cars.
Scott

Running higher than 87 doesnt KILL performance, neither does octane booster, it just makes the cumbustion cooler to reduce detonation and pinging.

 

[HISSIN50]

You guys seem to be picking around the edges. The octane thing needs to be related to timing. If a car does not ping on 87, running 93 (without increasing timing) does lower performance and increase emissions.

Running a little bit shy of detonation with any grade of gas (and the corresponding timing needed to reach this near detonation threshold) should net near equal results. But timing and octane do need to go hand-in-hand. If one changes, so should the other (for this argument).

I would also note that running on the ragged-edge before the onset of detonation can reduce power - yet another reason to not run right at the verge of pinging.

 

[mo_dingo]

You guys seem to be picking around the edges. The octane thing needs to be related to timing. If a car does not ping on 87, running 93 (without increasing timing) does lower performance and increase emissions.

Running a little bit shy of detonation with any grade of gas (and the corresponding timing needed to reach this near detonation threshold) should net near equal results. But timing and octane do need to go hand-in-hand. If one changes, so should the other (for this argument).

I would also note that running on the ragged-edge before the onset of detonation can reduce power - yet another reason to not run right at the verge of pinging.

Exactly. Maybe I shouldn't have said "kills performance", it just lessens performance. I don't have any figures to quote, so I can't say specifically how much.

Idealy you want to be around 13.0 - 13.5 a/f ratio when at WOT. Anything lower or higher also lessens performance. Obviously when you are just crusing at part throttle you will see 14.64 a/f because you aren't looking for performance, just fuel economy and little emissions output.

I always thought it was strange. Why bump the timing up if you have to run 93 octane just so it won't ping. It seems like the two would balance themselves out and very little if any performance gain will be had. I think bumping it to 14* gets you about 7-8hp on a stock motor, according to a dyno book about the 5.0's.
Scott

 

[NotQuik]

my car had been pinging as well, and I cleaned my maf finally and that cured my problem.

 

[titaniumsc03]

what i meant is you will gain more performance running 93 with your timing higher, than with your timing lower running 87, therefore 93 will give you more power due to the lack of detonation
Russell

 

[94droptop]

One other thing to consider. From your list of mods it shows you are running the stock heads. When our cars start to get high mileage carbon can build up on the pistons and on the valves and valve chambers effectively creating more compression and also hot spots.

You could try using some GM top engine cleaner to try and clean out the carbon. It is cheap to try and you might be surprised at the results.

 

[reject5.0]

^Where could a person get some of that...and what is it?

 

[HISSIN50]

^Where could a person get some of that...and what is it?

It is similar to Seafoam, which can be had from parts stores. A search of Seafoam will yield about 10000 threads.

Good luck.

 

[mo_dingo]

what i meant is you will gain more performance running 93 with your timing higher, than with your timing lower running 87, therefore 93 will give you more power due to the lack of detonation
Russell

IMO, I seriously doubt it. Like I said, from the dyno books, on a pure stock 5.0 HO motor, you will only gain 7-8HP bumping it to 14*. That is it. Then stick 93 octane in your gas tank, and you are back at where you started.....

One other thing to consider. From your list of mods it shows you are running the stock heads. When our cars start to get high mileage carbon can build up on the pistons and on the valves and valve chambers effectively creating more compression and also hot spots.

You could try using some GM top engine cleaner to try and clean out the carbon. It is cheap to try and you might be surprised at the results.

I tried that stuff, and a lot of it. Same with sea foam. 500 miles later, with my blown head gaskets, I yanked the heads, and there was a seriously thick layer of carbon all over the CC's and pistion tops...I don't think that stuff even works. But that is the major problem with her car; Which can only be alleviated by yanking the heads and getting the brush wheel to them.

Or get a tweecer or dyno tune and up your MAF transfer curve 5% and kill some timing while you are at it. That will definately do it.
Scott

 

[MysteryMachine]

I will never understand where you guys get the idea that higher octane kills performance. They make higher octane for a reasone its higher grade for higher performance cars hence why racing fuel is like 100 something. If i run low grade gas in my car it runs like ****

 

[HISSIN50]

MM, note what I posted before. The difference in performance with an additional 5 octane points (the spread here is only 4 actually; 89-91) is not going to do much. Race fuel is an entirely different animal - a real tangible difference. I think most of us are talking about pump gas here.

Otherwise, using toleune is about the best way to mimic race fuel w/o buying race gas.