Bosch Platinum 4

prote5

Member
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2002 Mazda Protege5, 2003 VW Jetta GLI
I recently replaced my stock sparkplugs with the platinum 4 by bosch. I read and heard about these sparkplugs causing problems in some cars, particularly n/a vehicles. Does anyone have any info on this? Also, if anyone reading this also made the switch please tell me if you've experienced any problems. The only thing i've noticed is 30 more miles on a tank of gas (93 always) but no problems yet.... Also, today I switched from regular motor oil to synthetic (mobil 1) but didn't like the $40 price tag on 4 quarts of oil and a $12 filter (mobil 1). Is there any significant difference in the oil & is it worth the extra money? If so, which products do you recomend? Thanks....
 
I have the p4 plugs and I haven't noticed anything wrong. I do get a stutter in the idle every great once in a while, but that's from the intake.

Shouldn't be much difference in the full synth and semi which I use. Just change the oil regularly. I also use the NAPA silver oil filter. The only reason to use full synth in a car is with hightemp stuff like a Turbo application. Full synth is more resistant to thermal breakdown, that's about it, ie, it retains it's viscosity rating longer.

Also, try using the intermediate rated gas. The car is actually made to run on that octane rating. You will get better mileage at the sacrifice of a little power. I've gotten a max of 33mpg on middle grade gas. I'd get more if I didn't have undersize tires.
 
hi prote5! I'm new here also but I work at a lube shop and from my experience and knowledge really the only advantage to synthetic oil over regular oil is the length of time it is supposed to last but I even question that. So I really think that using synthetic oil is a waste of money but that is my opinion and everyone has there own. Also why are you using premium unleaded fuel??? The cars are set up to run on regular unleaded (87). By running premium you may actually be losing power and hurting your motor more than helping it. Our timing isn't set to burn the fuel fast enough for premium fuel. Instead by using it your motor is not burning all of the fuel and it is making deposits in your combustion chamber. Later
 
The higher the octane rating, the slower gas burns. That's why if you have an issue with pinging (detonation), your fuel is burning too fast, ie just the heat generated by compressing the air fuel mixture is igniting it (like in a diesel motor).

Our computers should be set up to use higher octane rated gas, but it will set timing to make extra power.

I've tried regular 87 and I got worse mileage. I use 89 all the time. Also, mileage varies due to brand of gas. I seem to get the best mileage from Chevron here in town. Our gas is oxegenated, so that robs some mileage. Chevron is one of the only companies to re-refine the gas that it buys to make sure that you are getting the right rating of gas. All gas companies buy gas from whoever they can get it from, so you may be getting arco refined gas at an Exxon station, etc. I've also found out that Citgo gas gives me good mileage, plus they have the added benefit that they buy no crude from the middle east. :D
 
Fancy spark plugs and 91 octane fuel = waste of money.

You won't see any performance gains from the Bosh +4's or any other "high output" spark plug. If anything, all they will do is run hotter than stock, increasing the need for higher octane fuel, which our cars are not designed to use.

The "performance gains" claimed by the use of fancy spark plugs, "high output" spark plug wires, and high-octane fuel are marketing hype, or what users of these products *think* are performance gains.

Stock = reliable and trouble free. Anything else is just hype.

~HH
 
hotter spark plugs mean that bigger spark is produced, in turn your fuel burns more effeicintly thus giving better fuel economy, lower emissions, and of course, more power! not that much power gain, but it still helps a lil... and all those lil things add up.
 
GreenPic said:
hotter spark plugs mean that bigger spark is produced, in turn your fuel burns more effeicintly thus giving better fuel economy, lower emissions, and of course, more power! not that much power gain, but it still helps a lil... and all those lil things add up.

Sorry man - not a single statement you made is correct.

First of all, the stock spark is more than sufficient to burn the fuel. A "bigger" spark does not burn the fuel any more "efficiently" or "completely". Fuel burns. Plain and simple. Take this example:

We've all done the "blowtorch with the hairspray" before, right? Well, say you sprayed the hairspray (fuel) on a bigger flame - does the spray burn any more? Any faster? Any better? Nope. It burns - it combusts. Once the combustion process is started, there is no stopping it. All that is needed is enough spark to START combustion, and the stock setup is more that adequate for that. So long as the spark can ignite the fuel/air mixture, the combustion process now takes care of itself. "More" or "Hotter" spark does not cause the combustion process to happen "quicker" or "better" in any way.

Now using hotter spark plugs will HURT your performance. Why? Because a hot engine is not a good thing. If your fancy spark plugs raise the temperatures in the combustion chambers, the fuel now has a tendency to ignite BEFORE the spark, simply from compression (this is called detonation). This is not good, and can even cause severe engine damage, especially in forced induction vehicles.

You also now wind up with some fuel that is burnt already before the spark, which reduces the effectiveness of the spark. It does not have as much fuel to ignite. It is now also trying to ignite the remaining fuel in an chamber with less oxygen, and an abundance of exhaust due to the pre-burnt fuel. No good.

So running "hotter" spark plugs in a vehicle not designed to use them will hinder performance, not help it. Any power gains are imagined.

Your statement is exactly what the manufacturers of those products WANT you to believe - it's hype.

~HH
 
I have no opinion about the spark plugs, but I use Mobil1 5W30 synthetic oil simply because of the weather extremes we get up here in Quebec : -40F to +90F (dry to humid) and the engine sounds "smoother". Plus, I use to race go-karts (Honda 4 cycle ones) and I saw the difference it made in this type of engine.

Yes synthetic IS expensive, but I keep my cars from 6 to 10 years so...

My .02
 
hihoslva said:
Sorry man - not a single statement you made is correct.

I could say the same of your statements...

First of all, the stock spark is more than sufficient to burn the fuel. A "bigger" spark does not burn the fuel any more "efficiently" or "completely". Fuel burns. Plain and simple.

Stock spark is sufficient to burn the mix, but because of the economics of building a car and making it affordable, the BEST plug is not used by Mazda. All manufacturers make sacrifices to keep cost low. If they didn't, we'd all be drivin in totally pimped out cars that are factory. Factory tires would be the best available, etc...

Take this example:

We've all done the "blowtorch with the hairspray" before, right?

Bad example, because hairspray is actually more volatile than the a/f mix.

Now using hotter spark plugs will HURT your performance. Why? Because a hot engine is not a good thing. If your fancy spark plugs raise the temperatures in the combustion chambers,

OK, a hotter spark plug does not increase the temp of your engine. The thing that will increase the temp of your engine is running too lean. A leaner mix burns hotter because there is more O2. O2 burns, too... Running too rich, causes your engine to run cooler, because fuel acts as a coolant.

Detonation occurs because the a/f is too flamable and just by compressing the mix, it starts to burn. Remember, lower octane rated gas is more volatile than higher octane gas. It's a simple rule of thermodynamics, if you take a quantity of a gas and compress it's volume, the temp of the gas will rise. This is how a diesel engine works. The compression ratio of diesel engines is MUCH higher than that of a car. Our cars run somewhere around a 10:1 ratio, meaning that from BDC to TDC, the mix is compressed to 1/10 it's original volume. In a diesel, that ratio is closer to 20:1. This is also why diesels rev lower and make more tourque vs. HP. The longer the stroke (need to compress the diesel mix) the more torque. The shorter the stroke, the more HP.

You also now wind up with some fuel that is burnt already before the spark, which reduces the effectiveness of the spark. It does not have as much fuel to ignite. It is now also trying to ignite the remaining fuel in an chamber with less oxygen, and an abundance of exhaust due to the pre-burnt fuel. No good.

Do you remember the original CVCC enigine that Honda had? It had a precombustion chamber right around the spark plug. The purpose of this was to pre-ignite a leaner a/f mix so that that pre-burned fuel could burn the rest of the charge. They had to do this because there were no plugs like the P4s or the Iridium. Today's cars burn an a/f mix that is much leaner than yesterday's cars. This is to increase mileage and decrease emmissions. The less flamable something is, the 'hotter' you have to get something to ignite it, right. Take for example, sawdust compared to a piece of wood. It doesn't take much effort or time to burn a pile of sawdust, but it takes a little bit to ignite a piece of wood. That's what we're talking about here, not Hairspray. If you wanted to use the hairspray example, you would have to spray the liquid out of the can into a container. If you ignite that liquid, it would burn slowly, whereas the atomized hairspray coming out of the can ignites quickly.

So running "hotter" spark plugs in a vehicle not designed to use them will hinder performance, not help it. Any power gains are imagined.

The only thing that's imagined here is your theory... :D

I'm no automotive engineer, but neither are you. What I have done is raced and tuned 2-stroke motorcycles. You would not belieive what tuning one of those will teach you. We normally change spark plugs, a/f ratio and carb jets according to the temp/humidity/elevation anything that can affect the mix.
 
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While I will admit you bring up some valid points, I'm sticking by my summation, which is that fancy spark plugs do NOTHING for performance in an otherwise stock car, and can in fact hinder performance.

You've tuned motorcycles, but you also change the a/f ratio, and carb jets. In this case, spark plugs can make a big difference. But in a 4 cylinder, computer-controlled engine, where the air/fuel mix is changed by the computer, the spark plugs and the amount of spark they produce are not taken into consideration by the computer algorithms - only the timing is changed, and not the force of the spark.

This discussion is not about fully-tuned motors - it is about the benefits or detriments of more powerful spark plugs in an otherwise stock engine.

About the heat generated - this is not myth, I have witnessed it in my own vehicle. There is no way that a spark plug alone can cause a lean condition. Upon changing to SplitFire plugs in my Miata, I witnessed some knocking and pinging. Under the advice of a mechanic, I got rid of them and went back to stock NGKs - the pinging went away completely and immediately. He explained that the reason was they burn too hot, and I was getting detonation, and pre-ignition upon compression from the excess heat. I did also notice a slight increase in engine temp gauge readings while those plugs were installed, so what he said makes perfect sense.

The basics of combustion prove that a "bigger" spark does nothing unless you change other factors. You might not agree with my harispray example, but frankly, your sawdust example is worse. So let's clear that up, and use the a/f ratio for it.

Forgetting compression for a second; if you put equal amounts of a mixture of atomized gasoline and oxygen into two containers, there will be no difference in the force or speed with which they combust based upon the spark that is used to ignite the mix. If the containers were swimming pool-sized, and you ignited one with a match, and the other with a flamethrower, they would still BURN and COMBUST at the SAME rate and with the same amount of energy.

Using wood as an example is not a good analogy. But another decent one is to take balloon filled with hydrogen. Use the Hindenburg zeppelin if you like! ;). Would the hindenburg have burned FASTER or with more FORCE and ENERGY if the explosion was caused by a match flame rather than a simple tiny static spark? No, it wouldn't. All that matters is that the ignition source is powerful enough to start combustion.

Combustion in an engine is nearly instantaneous. The duration or force of the spark makes no difference in the rate of combustion so long as the spark IS forceful enough to ignite the mix. We're not talking about the combustability of different octane grades of gasoline - that's a whole other discussion. This is using the same fuel, same a/f ratio, and ONLY changing the characteristics of the spark - nothing else.

By adding other factors into the mix, the spark characteristics can play a role, of course. But this is about hot plugs on a stock motor.

The fact that today's cars run leaner than ever before makes my argument even more valid - that the use of plugs that raise combustion chamber temperatures has an adverse effect on performance. If a lean condition causes excess heat, and today's cars run quite lean as compared to cars of years prior, then today's engines generally run hotter. Thus, the need to NOT induce excess heat is even stronger, and the tendency for an engine to exhibit detonation from slight temperature increases is higher. In other words, in todays cars it's even MORE important to keep the plugs in the proper heat range. Again - I witnessed this first hand in my Miata.

If you want to refute my theory about hot plugs, that's fine. But you have to do it without changing any other factors in the engine. We can't "tune" our Protege's like a 2-stroke motorcycle engine, or an old carbuerated V8. With proper engine tuning, hotter plugs can in fact give more power and/or fuel economy. But without tuning the engine to utilize the extra spark (which the ECU of our cars is not designed to do on its own), hot plugs are an excercise in futility, and a waste of money.

~HH
 
Don't know about perfromance increase...

but I've been using Bosch Platninums in my cars since they came out. I've done it for the reliability factor. I put a set of Plus4s in my Saturn and they went 104,000+ miles. I pulled the plugs when I sold the car to see what they looked like and they looked perfect, so they went back in.
As for synthetic lubricants, I feel they are well worth the extra $$$. Hell, I even run my 4 stroke string trimmer and lawn mower on Mobil1. Synthetic lubes in all of my transaxles have always improved shifing and synchronizer life.
Both of these products will go into my P5 when the time comes. Jim
 
AMSOIL, Mobil 1, and Golden are three of the best oils. Dont buy mobil1 filters, though, they are overpriced and motorcraft/PureOne filters work better and cost much less. AMSOIL filters also work better and cost less.
Synthetics have better pour characteristics in the extremes. They also contribute to a much lower coefficient of friction. The basic lubricating agents in synthetics are called PAO's. Different synths have different PAO concentrations. AMSOIL has the highest PAO concentration of oils sold in the US, in Europe you can buy "pure" PAO's that will last well over 100k miles.

I have been a 3k miles change person for my entire life, religiously. But even I am going to start changing according to the Mazda schedule (but with a filter change every 7.5K as well). AMSOIL typically says you can double the change interval based upon the manual, as long as the filter is changed regularly. There are over-the-road trucks running up to 100K miles on ultra-high PAO lubricants.
 
I did NOT bother reading all the LONG ass posts above. I just wanted to throw my 2 cents in the mix, ...

Walmart has the 5 Q (or is it 5L) bottle of Mobil1 at a regular price of 18.00. You just have to be able to find it...
 
Also, today I switched from regular motor oil to synthetic (mobil 1) but didn't like the $40 price tag on 4 quarts of oil and a $12 filter (mobil 1)

:wtf:

Dude. I've never heard of oil that expensive. here in the great state of Arkansas the most expensive I've seen is still under $5 a qt. By the way I've just swiched from synthetic to regular oil. I don't think synthetic is worth the money.
 
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I switched to Mobil1 because of my frequent short trips.
The engine is only coming up to the hot temp when I pull into the parking lot at work.
Dino oil needs to be completely heated up to expel all the crap that it picks up from the engine. Synthetic doesn't need to be heated the same to do so.
 
I apologize, the TOTAL price of oil and filter was ROUGHLY $40 from Autozone. Anyways to my original question, should I replace the Bosch 4's with regular old Bosch Super's or what would you reccomend? Also, at 12,000 miles my car makes a tapping noise and doesn't sound to healthy. Could I just need a valve adjustment or what?? I hardly "rag" on the car and drive only half a mile to work everyday. I'll admit, I have redlined it on 3 or 4 occasions before but only when the situation called. Even with that, it doesn't have a lot of miles and the engine already sounds like crap..... This is my first Mazda (first brand new car) and so far i'm pleased with the looks, room, and handling but not so much with the engine or tranny.... I've had many other cars (3 MR2's, 1 CRX) that I pushed extremely hard (especially MR2's) and not once ever thought it didn't sound healthy and they had 100,000 plus miles.... It could be they were made to do that repeatedly (ran hard) and maybe the Prote is just a grocery getter with cool looks?? Either case, dont downgrade me cause of my opinions.... Its just a thought
 
Explain the "tapping" noise. And list any changes you have made to the car. BTW, a 1/2 mile drive to work is not super healthy for the car, and more importantly the cat. Just out of curiosity, why do you drive that short a distance?
 
You know what my spark plug recommendation will be...stock.

Where is the tapping coming from? Is it definitely the engine, or could it just be something a little loose in the exhaust, perhaps?

Your car should not need any kind of valve adjustment, especially with about 1 year's miles on it.

I'm not trying to harp on the subject, but it is possible that you have some excess carbon deposits from running those plugs, and that might be contributing to the valve tappet (assuming it is the valves tapping).

Also, are you running the correct weight oil?

I would simply take a trip to the dealer, and have them do a warrantee look-see. While you are there, it might be a good idea to see if they have any used Proteges with similar mileage on the lot, and start one up to see if it sounds like yours. If it does not, that's a good thing to show the service techs.

Best of luck.

~HH
 
Well, it's kind of hard too explain a noise over a message board but.... its like a "tick tick tick" metal noise that increases with gas applied.... like a valve tap, or the lifters tapping or something.... all I know when I first got the car it purred like a kitten and after some 7 months of use (12000 miles in 7 months!?, traveled a lot from Texas to Florida and back a couple times) it sounds like a diesel if you will..... i'm in the Air Force and live on base so my workplace is like .6 miles away..... as for the tapping I don't know what its from.... I change the oil every 3000 miles, USED to only put 93 gas in it, change gears for the most part at 2500-3500 RPM's while in the city.... but on the highway, all 1300 miles (Texas to Florida) the RPM's are at 4000 RPM's the whole way... could it be I put a lot of miles in such a short time? I doubt it.... it may be just a lemon??? Who knows....
 

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