Happy Bosch Platinum +4 Users ? (Or any Platinum Plugs)

[The Critic]

Are there any HAPPY users of Bosch Platinum +4 Plugs? Please list whether your:

1) Yr
2) Model
3) SOHC or DOHC
4) Miles on Plugs

Also, does anyone have any positive experiences with other types of platinum plugs, i.e. Bosch Platinum, Autolite Double Platinum, ACDelco Rapidfire, etc.

Thanks.

[RalliArt16]

I think there are a 'few' people on here who use bosch +4s and say they work fine.

I work in an auto parts store and of course here everyone proclaim the platinum, iridium, etc produce a "cleaner, better spark" and all that nonsense. From what I've read, the benefit of "premium" plugs is purely LONGER LIFE (and therefore less maintenance), period.

But whereas ngk coppers are like $1.79 a plug and "premium" plugs near $6.. i'll hold off them thanks.

[scsomike]

i thought the general opinion here was that neither the SOHC or DOHC motors liked platinum plugs?

[amazinghl]

Why bother, platinum makes saturn mis-fire.

[JC2002SILVERSC2]

i was told by autozone & gm mechanics that they burn up the pistons in our cars. i used them in my old 95 sl1 and you can feel the difference. it seemed to give more power but from what they told me it gets to hot. thats just what i have been told.

[Uzzy]

Originally Posted by scsomike

i thought the general opinion here was that neither the SOHC or DOHC motors liked platinum plugs?

It is, but as with anything, there is some dissent. But very little, obviously.

[TBone1082]

Personally, unless your car has a full ignition system, MSD or Accell or anything in it, I'd go with stock plugs. +4 Plat's are just a way to get more money out of people. From what I remember, unless you have more power going to the plugs, its not going to make much of a difference. Hence the same goes for wires. Unless you have the actualy FULL ignition wokred over, stick with stock, it costs less and will ultimately, make you car happier.

[sherrill]

NOTICE: Saturn fans; be advised about a potential problem using platnum type spark plugs installed in engines using the "waste spark" type of ignition system. Please be advised that any engine that uses the waste spark system will run BETTER on the STANDARD type of spark plug, NOT the platinum type. (this includes most (all?) Saturns and both my '98 and '99 SL-2 have this type) There is a scientific reason for this. It is because in a waste spark system, one half of all the spark plugs fire in REVERSE POLARITY. That is, the spark jumps FROM the SIDE electrode to the center electrode. (Normal polarity is when the spark jumps from the center electrode to the side electrode. That is one reason why spark plugs with high milage will develop a "dish" on the underside of the side electrode, where the spark, when it jumps from the center electrode will strike the bottom side of the side electrode and erode the metal and form a slight "dish" shape. This is one of the methods a spark plug will wear in a normal manner.) However, in a waste spark system one-half of the spark plugs are always firing in reverse polarity. This is because the high voltage ignition coil is connected in series with two spark plugs and the two plugs always fire simultaneously but are 360 degrees out of phase, i.e. one wire from an ignition coil is connected to the number one cylinder and the other wire from the same coil is connected to the number four cylinder. The same is true for the other coil except the other coil wires are connected to the number two and three cylinders. The number one and four and number two and three cylinders are always 360 degrees out of phase with each other. (This is the origin of the term "waste spark" because when one coil fires, only one spark plug ignites the fuel-air mixture and the other spark plug "wastes" its spark.) Now, the problem with the platinums is that the center electrode is very small and it is more difficult for the spark to to try to jump onto its "target" with a very small center electrode . The reason the standard design spark plugs will run better is that they have a much larger center electrode for the spark from the side electrode to discharge onto. This is why standard, i.e. Bosch "Super" or equivalent type plugs will run better in any engine using the waste spark ignition system. Engines with the coil over plug (COP) ignition system, (i.e. a seperate and dedicated coil for each cylinder) always run in normal polarity; so platinum spark plugs will work fine in these type ignition systems. Also, be aware that in order to use a waste spark ignition system, the engine must have an even number of cylinders. Five cylinder engines will always use a coil over plug (COP) system or a similar method with a dedicated ignition coil for each spark plug. - Sherrill

[desired name]

I found the Bosch Platinum good in my old chev pickup 305cu . it had a small oil leak past valves the fouled the 7 &8 plugs that didn't foul the Bosch Platinum plugs. they always looked clean. I think the +4 version is just a gimick it will only spark across one at a time.

[alleninpa]

Sherrill,
First off, the plugs are not connected in series, they are in parallel. I havn't had a coil pack apart yet, but I suspect that they are fired the same each time, and not reversing polarity. Even if this were the case, hitting a small target electrode with the spark thing is really stretching it. The spark is created ONLY because there is a large voltage difference between the ground and the electrode. There is no way it could possibly miss due to the small electrode.

Second point - This ignition system is not new to GM. I had the same thing on a 88 2.0L Cavilier, 89 2.8L cavilier, 93 3.8L Boneville, and 2000 3.4L montana. I run platinum plugs fine in all of those cars. (still have the Boneville and Montana.)

Basically what you are saying is that you should never run Platinum in a GM vehicle (since almost newer ones use the waste spark), which doesn't make sense, considering they are standard on most vehicles.

I don't see the issue with a spark not hitting it's target anyway on a waste stroke.

Some say that the engines run hotter with platinum plugs, which may be plausible. This would be due to a more complete combustion in the cylinder. If this is the case, the reason that they don't run well in saturns, is due to the saturns running rich to keep the engines cool. The richer mixture is harder to ignite with such a small spark, causing missing and eventual fouling.

[Luke]

> Sherrill <
Greatly appreciated your "waste spark" input/article. Very informative and appreciated the time to submit it to us.

[sherrill]

Allen: Unfortunately, you have misunderstood or misinterpreted my comments. No spark plug is ever connected in parallel with another spark plug. In the waste spark system, one coil and two spark plugs are ALWAYS in series. Not all GM vehicles use the waste spark system! (My son's 1999 Chev pickup truck uses a COP ignition system.) - Sherrill

[sherrill]

I forgot to mention this but platinum spark plugs have nothing to do with an engine running hotter or cooler. That is an incorrect statement, usually made by parts sellers trying to sell more expensive spark plugs. - Sherrill

[amazinghl]

Originally Posted by alleninpa

Some say that the engines run hotter with platinum plugs, which may be plausible. This would be due to a more complete combustion in the cylinder. If this is the case, the reason that they don't run well in saturns, is due to the saturns running rich to keep the engines cool. The richer mixture is harder to ignite with such a small spark, causing missing and eventual fouling.

Spark plugs have heat range, just so you know. If the platinum plugs are making your car run hotter, you're not using the correct heat range plug.
http://en.wikipedia.org/wiki/Spark_plug

[sherrill]

NOTICE TO ALL SATURN FANS: There seems to be misunderstanding on this most important subject, so please try to follow with me and I will try to be more specific and thorough so everyone will understand. (Also, be advised that have been aware that spark plugs have heat ranges for 40+ years.) Platinum spark plugs ALSO have heat ranges EXACTLY LIKE the standard type. Just because the spark plug is a platinum type does NOT make the spark plug a hot or cold plug. The HEAT RANGE of a spark plug is determined by the LENGTH of the inside or bottom center electrode and its surrounding insulator, from the tip of the center electrode and its surrounding ceramic insulator to the steel body or shell of the plug. (The body of the plug then conducts the heat away from the tip of the electrode to the colder cylinder head. Hot plugs have long center electrodes and long center insulators. Cold plugs have short center electrodes and insulators. This is the ONLY factor that determines if the spark plug is a hot or cold plug. The spark plug being either a platinum or standard type has NOTHING to do with its heat range. Also, I will now explain in more detail why waste spark ignition systems are "series " connected. Please be advised that in a waste spark system the high voltage current that fires the spark plug travels, in series, from one terminal or lead of the ignition coil to the spark plug wire, from the wire to the center electrode of the spark plug, it then jumps the gap to the side electrode, from the side electrode it travels through the cylinder head to the side electrode of its mating cylinder; i.e. cylinder 1 is mated to 4 and cylinder 2 is mated to 3 on the SL-2 DOHC engine. Each cylinder pair is 360 degrees out of phase with its mate. (This is why each side of the ignition coil is connected to these respective spark plugs.) From the side electrode it then jumps the gap to the center electrode, it travels from the center electrode to the spark plug wire and returns to the other end or terminal of the ignition coil, thereby completing the circuit through the coil. Therefore the ignition coil, wire, No. 1 spark plug, cylinder head, No. 4 spark plug and its wire to the ignition coil are all connected in a series circuit; thereby completing the loop and permitting current to flow. Also, as further proof of this, if one disconnects one spark plug wire, it does not matter which one, the mating cylinder spark plug will NOT fire, because the SERIES circuit is broken. (If the circuit was a parallel circuit, and one spark plug wire was removed, the other spark plug would still continue to fire.) It its the PATH THE CURRENT FLOWS that determines if the circuit is a series or parallel circuit. FURTHER, be aware that the reason waste spark systems do not perform well with platinum spark plugs is NOT because the plugs are platinum tipped! The reason is because the center electrode on platinum plugs is usually made very small and the spark is delayed trying to find its postive "target", i.e. the center electrode. It is easier for the spark to jump to a larger positive "target" than a small one. Standard spark plugs have much larger center electrodes (target) and make it easy for the spark to jump from the side electrode to the center electrode. Remember, when the spark jumps from the side electrode to the center electrode, it is firing in REVERSE polarity.- Sherrill W

[GreenSC2]

This is one of those inflamatory threads that is just bound to get people fighting.

I don't care if people use them or not, just don't come here whining if they cause problems.

[willfxp]

I think Sherrill's threads should be posted somewhere like in the HowTo section. It's very good and detailed information.

(Of course, I don't know if it's accurate or not, but sure sounds like it!)

[The Critic]

I discussed w/one of my contacts today about Bosch Platinum+4 Plugs. He is a GM engineer working for Cadillac in engine design. Here's what he has to say:

A number of Cadillac owners have posted of poor driveability with Bosch
plugs. I ran the Bosch+4 plugs on the dyno several years ago and they
hurt HP. We always assumed it was because the extra ground electrodes
shielded the flame kernal and delayed combustion but never really tested
them any further as we had no intention of using them for anything. The
Bosch "platinum" plugs are just platinum center electrodes, not the ground
electrode. With a direct fire ignition system where one plug on a coil
fires from the center electrode to the ground electrode and the other fires
from the ground electrode to the center electrode BOTh electrodes need to
be platinum to avoid severe erosion. Without dual platinum it is pointless
to use the single platinum plugs in that type of ignition system (like you
have too). So, based on principle, their advertising is misleading and the
+4's are known to cause power loss and driveability issues. BTW, they went
to the +4 concept with the platinum center electrode so as to have "extra"
electrodes when some started to erode due to the direct fire ignition
systems. I don't know that they are bad in a all applications but I don't
want to buy them to test them for them.

So theoretically, if I have a double platinum plug from ACDelco or Autolite, with a normal sized electrode, shouldn't I be good to go? I can see where the problem is with the smaller sized electrodes or single platinum plugs (corrosion), but wouldn't the double platinums solve this?

Thanks for the help on a confusing subject!

[cindy_and_lee]

I'm gonna go out on a limb here and tell you "MY EXPERIENCE WITH ALL BOSCH PLUGS"

THEY ARE JUNK

they burn out usually in just a few weeks (if that long) of installing them... I worked at a repair shop in Nashville for about a month... before i started working there Advance Auto Parts had some sort of deal with him to get him to use these plugs.... I spent damn near the entire month going through every car that he'd installed these plugs in and replacing them with autolites, champions, ngk's... whatever the manufacturer suggested... all these cars come in with stumbling, hesitation, poor starting... numerous problems... all dealing with the plugs... all of them had Bosch plugs of some type in them... replaced the plugs and the vehicles would start up and drive normally again...

it all deals with the way that Bosch has the electrode contained in the porcelain... it is the same height... once this small area has burned up the plug no longer fires correctly... then the problems start

hey sherrill... when posting... try to break up your post a little bit it makes it much easier to read... just trying to help...

Lee

[wolfman]

Originally Posted by alleninpa

Sherrill,
First off, the plugs are not connected in series, they are in parallel. I havn't had a coil pack apart yet, but I suspect that they are fired the same each time, and not reversing polarity. Even if this were the case, hitting a small target electrode with the spark thing is really stretching it. The spark is created ONLY because there is a large voltage difference between the ground and the electrode. There is no way it could possibly miss due to the small electrode.

Second point - This ignition system is not new to GM. I had the same thing on a 88 2.0L Cavilier, 89 2.8L cavilier, 93 3.8L Boneville, and 2000 3.4L montana. I run platinum plugs fine in all of those cars. (still have the Boneville and Montana.)

Basically what you are saying is that you should never run Platinum in a GM vehicle (since almost newer ones use the waste spark), which doesn't make sense, considering they are standard on most vehicles.

I don't see the issue with a spark not hitting it's target anyway on a waste stroke.

Some say that the engines run hotter with platinum plugs, which may be plausible. This would be due to a more complete combustion in the cylinder. If this is the case, the reason that they don't run well in saturns, is due to the saturns running rich to keep the engines cool. The richer mixture is harder to ignite with such a small spark, causing missing and eventual fouling.

Sorry but WRONG.. Those engines you mentioned (completely different animals) also have CAMSHAFT POSITION SENSORS, which the ignition system uses to calibrate the timing. The "S" series Saturns do NOT. They use the weaker waste spark measured resistance to provide the calibration for the ignition timing. The use of a non-recommneded (platinum in this case) spark plug upsets that calibration value and results (in most "S" series) in a MISFIRE or misfire code being generated. Sherrill's take and description is 100% CORRECT.