Bosch spark plugs

[Nick R]

I typically prefer NGK or Nippondenso for plugs in cars. In the Jeep I use Champion Coppers because they run better than anything else in them.

Worst plug I ever used was an Autolite for a Briggs flathead, it misfired constantly and wouldn't run. Pulled it, stuck an NGK in there and ran perfectly.

 

[Silk]

I've heard this before on US forums - where are your sparkplugs made ? I know the US platinum plugs are different from what we get here so that could be one reason. I used to sell and fit Bosch plugs in my workshop and never had a problem with any. Best thing about going Bosch was that I halved my stock over the NGK I carried before - instead of having ISO and JIS plugs, Bosch just do the ISO, and supply a longer top nut for JIS, brilliant. I've also used the Plus 4 with no problems, and have had them in my motorcycle for the last 4 years or more. They give no advantages apart from longer life, and I'd rather go with the cheaper Plus 4 's for that rather that plats.

 

[kr_bitog]

The most problematic of the Bosch plug is the one with fused center electrode. Many times this is covered/fouled and lead to difficult start for non-fuel injection engine. However the new OE Iridium is great, last long and cheap. The only thing is just their heaat range may not map exactly with NGK/Denso/Champion that sometimes takes a while to map to the correct heat range required.

 

[Silk]

Originally Posted By: kr_bitog
The most problematic of the Bosch plug is the one with fused center electrode.


That's the one, we don't get it here.

 

[Nick R]

Originally Posted By: Silk
I've heard this before on US forums - where are your sparkplugs made ? I know the US platinum plugs are different from what we get here so that could be one reason. I used to sell and fit Bosch plugs in my workshop and never had a problem with any. Best thing about going Bosch was that I halved my stock over the NGK I carried before - instead of having ISO and JIS plugs, Bosch just do the ISO, and supply a longer top nut for JIS, brilliant. I've also used the Plus 4 with no problems, and have had them in my motorcycle for the last 4 years or more. They give no advantages apart from longer life, and I'd rather go with the cheaper Plus 4 's for that rather that plats.



Most of the Bosch plugs I've seen were Made in India tbh. 99% of NGKs were Japan, (the others USA) Denso Japan, and Champion USA.

 

[Audios]

Bosch makes a few different lines of spark plugs. The +2 and +4 are terrible, cheap POS that we constantly see problems with at my shop. The OE Bosch design, like the FGR-6KQE that comes in Porsche Cayennes, is a great plug and Ive never seen issues with it, even though its exactly the same design as the +4. I think it comes down to center electrode material. The factory Boschs are usually Platinum as a center electrode, and list for 18ea, where the cheaper 2 and 4 use a copper electrode, then switch to platinum at the tip. These also list for 5-7 ea, so you get what you pay for. I have a parts program that can tell me the OE or recommended plug if anyone wants to know whats recommended for their car.

 

[asand1]

Originally Posted By: punisher
Originally Posted By: asand1
Plugs are plugs, they are all good. The problems stem from heat ranges differing between manufacturers due to losses in translation.


No, there really are some differences in the way a plug performs with a specific ignition system. That is one reason I always used the OEM plug whenever possible when doing plug replacements.

I have too much experience with Fords. I saw lots of Bosch+4, and Splitfires thrown in by owners looking for that "performance edge". Pulled a lot of Bosch and Splitfires correcting rough idles, random misses, and MIL lights. Customer had to eat the bill then as warranty sure wasn't going to cover that.

If there was some miracle plug that improved performance and mileage, you can be darned sure the OEMs would use it. Truth is it is a lot easier to get it wrong than get it right concerning spark plugs.


Marketing gimmicks aside, if I put Bosch coppers in my VQ30, it will start to miss and run [censored]. Is it because the plug is inferior? No, its because while the plug fits, the heat range is not perfect and will begin to foul.Add to this the platinum and iridium plugs that may not be the correct gap and could allow the spark to blow out or not be fat enough. Perhaps the plug is or is not a resistor type?
The VQ was built to use a specific NGK Plug, so while Bosch plugs are high quality why would I install something that is only "compatible" rather than what is recommended.

 

[heyu]

Bosch plugs do not work in alot of vehicles because All the funky looking plugs Bosch has come up 2 prong ,,4 prong no prong whatever,,SPARK IS SPARK ,,It all goes to the nearest conductor , wider heat ranges with Iridium sure ,,Overall all the same ,Bosch = waste of money

 

[GC4lunch]

Originally Posted By: heyu
Bosch plugs do not work in alot of vehicles because All the funky looking plugs Bosch has come up 2 prong ,,4 prong no prong whatever,,SPARK IS SPARK ,,It all goes to the nearest conductor , wider heat ranges with Iridium sure ,,Overall all the same ,Bosch = waste of money

Yet another subscriber, it seems, to the fallacy that, because Bosch multi-contact plugs are unsuitable for many applications, therefore all Bosch spark plugs are bad. It is a fallacy because it is a non-sequitur.

 

[asand1]

Originally Posted By: heyu
Bosch plugs do not work in alot of vehicles because All the funky looking plugs Bosch has come up 2 prong ,,4 prong no prong whatever,,SPARK IS SPARK ,,It all goes to the nearest conductor , wider heat ranges with Iridium sure ,,Overall all the same ,Bosch = waste of money

Not all Bosch plugs are multi electrode. I am sure that they are even OEM in some vehicles.

 

[Virginia_Oilcan]

I don't doubt the negative reports on the Bosch +2/4, but my own experience contradicts them. I have run at least a half-dozen sets of Bosch +2/4 Platinums in an older (94) Honda Civic along the way. Always ran fine, and have always gotten at least 25K miles out of them. The car is over 450K miles at this point, and still reliable.

 

[GMBoy]

Originally Posted By: asand1
Originally Posted By: heyu
Bosch plugs do not work in alot of vehicles because All the funky looking plugs Bosch has come up 2 prong ,,4 prong no prong whatever,,SPARK IS SPARK ,,It all goes to the nearest conductor , wider heat ranges with Iridium sure ,,Overall all the same ,Bosch = waste of money

Not all Bosch plugs are multi electrode. I am sure that they are even OEM in some vehicles.



Bosch were OEM in my 2008 Cadillac CTS 3.6DI. They lasted 50k miles and I got misfires (P0300 and P0301). Changed them to Autolite double Platinums. My Dad has the same car and we had to change his plugs too for misfires at 53k miles. Also went Autolite. I could tell they were Bosch because of the unique Bosch numbering stamped in the plug shell. The were single electrode style.

I've used Bosch Iridium Fusions with decent results. I had bad results with the Bosch regular platinum in the Buick Turbo GN back in the 90's....copper is better in that application anyhow.

 

[cutter]

No problems with the Fusion IR in 1zz-fe.

 

[PandaBear]

As a store employee, I'd recommend you tell your customers to stick with what the manual says. Bosch, Champion, Autolite, NGK, Denso, AC Delco, etc may work even if they are not OEM, but if the customers come back, you or your manager would be on the hook.

Now they insist they want to buy it and try it out, don't fight them. Maybe they have already tried it and like it, maybe they just want to get it for the rebate, or they just feel lucky.

Personally I'd use if if the price is right on a car that's easy to change plugs. I'd only stick to OEM recommended plugs if it is hard to change, like a V6 that requires disassembling the intake manifold.