I work at an auto parts store, and have been told Bosch spark plugs don't work well with American vehicles (GM, Dodge, but especially Ford.) I want to help my customers make the best decision. Usually I recommend the original plug manufacturer and type. I'd like to find out though if what I've been told about Bosch plugs is true, they seem like very nice plugs. Any thoughts or definitive answers out there?
Bosch spark plugs
- Thread starter Hotel55
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Yup. Newer Cars w ith misfire counters may throw a code with bosch plugs. COMMON problem on the jeep boards I frequent. Often a jeep 4.0 won't even start with new bosch platinums in it. Happens when the parts store is having a sale then the threads start showing up.
"Definitive" is going to be subjectively opinionated I'm afraid. What I can tell you is that I installed Bosch Platinum plugs in a couple of GM 3800 Series II engines (one naturally-aspirated L36 and one supercharged L67) years ago and never had any problems. OE plugs were NGK and with the Bosch ones, the engines ran just as smooth and solid.
i agree i don't like them. I use NGK in almost everything.
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Use exactly what your owners manual specs.
Switching to a different plug will not help
Switching to a different plug will not help
question? if a vehicle is several years old the o.e.m. plug may not be the latest design, or it may be a plug that the manufacturer used because it was cheap or linked in someway to the car builder. can we assume that no later or premium design can be better? I know on old Volvos the common wisdom is to use the old style regular Bosch, but some folks love NGK, and similar on older BMW's. Not criticizing but logically a newer design should be better. BTW I used to have an old Escort, and had friends with similar, and you better have Motorcraft plugs, cap, rotor, and plug wires or you had problems. Never figured that out.
The problem with the Jeeps and Bosch Platinums is with the waste spark ignition. It fires 2 plugs at the same time and having 1 Platinum tip on the plugs makes it run bad.
http://www.jeepforum.com/forum/f9/help-misfire-1295514/
http://www.jeepforum.com/forum/f9/help-misfire-1295514/
I've always enjoyed excellent results with NGK plugs in all my vehicles... Denso's are very good, too!
Interestingly enough Motorcraft/Autolite plugs seem to be the choice for many in the Ford Truck Enthusiasts Forum and that covers multiple decades of Ford trucks, as in "back to F1's".
When NGK's are on sale with rebates (never seen them FAR, but pretty close!) I usually buy the limit, ofetn just 16 plugs.
Cheers!
Interestingly enough Motorcraft/Autolite plugs seem to be the choice for many in the Ford Truck Enthusiasts Forum and that covers multiple decades of Ford trucks, as in "back to F1's".
When NGK's are on sale with rebates (never seen them FAR, but pretty close!) I usually buy the limit, ofetn just 16 plugs.
Cheers!
Ford uses Bosch ignition systems in many of its cars.
Bosch plugs are excellent. No better of worse overall than Denso, NGK, ect.
Bosch plugs are excellent. No better of worse overall than Denso, NGK, ect.
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Bosch plugs are just fine as long as you use the type your car was designed for. I'd have no issue at all using their OE-style plugs if I needed some.
I think far too many people 'upgraded' to those +2 and +4 plugs from regular single-strap coppers or platinums, and blamed Bosch products in general when they had issues.
I think far too many people 'upgraded' to those +2 and +4 plugs from regular single-strap coppers or platinums, and blamed Bosch products in general when they had issues.
Long long ago I worked on a Pontiac that had been tuned by a local shop. It came to us because it would skip for a few seconds every morning when started. It would only do this the very first time it was started in a day. Needless to say it wasn't easy to diagnose. All of the readings looked normal on the TechI and on an oscilloscope/Allen. We pulled the plugs and checked them carefully to make sure the shop had not cracked a plug installing them. The shop that tuned it had already spent about a week on it.
It had Bosch Supers in it and they were the correct ones per Bosch. We tried a lot of stuff directed by GM Tech, including a new calpack. When something did not fix it we removed/undid it.
Finally out of frustration we put a set of ac delcos in it.
Guess what? Yep - fixed it. (and yes that was suggested earlier but no one would pay for it)
We did a little research and determined that the heat range on the Bosch was not quite right.
Some older stuff doesn't like the fancy plugs either, but that is the only car I ever had problems with supers in, of course I will not use them in an american car any more period since I spend a good part of a week messing with it - very little of which I got paid for.
It had Bosch Supers in it and they were the correct ones per Bosch. We tried a lot of stuff directed by GM Tech, including a new calpack. When something did not fix it we removed/undid it.
Finally out of frustration we put a set of ac delcos in it.
Guess what? Yep - fixed it. (and yes that was suggested earlier but no one would pay for it)
We did a little research and determined that the heat range on the Bosch was not quite right.
Some older stuff doesn't like the fancy plugs either, but that is the only car I ever had problems with supers in, of course I will not use them in an american car any more period since I spend a good part of a week messing with it - very little of which I got paid for.
Plugs are plugs, they are all good. The problems stem from heat ranges differing between manufacturers due to losses in translation.
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.
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.
Originally Posted By: Bottom_Feeder
Bosch plugs are just fine as long as you use the type your car was designed for. I'd have no issue at all using their OE-style plugs if I needed some.
I think far too many people 'upgraded' to those +2 and +4 plugs from regular single-strap coppers or platinums, and blamed Bosch products in general when they had issues.
^^^This. Exactly.
If you read the posts in this thread, the people who say that all Bosch plugs are bad, or those who say that you should match the nationality of the spark plug to the nationality of the car (snort! really?) have no Bosch experience other than with the Bosch +2 or +4 (or, recently, Bosch Ir Fusion) plugs, or have been reading posts on internet forums where people had bad experience with Bosch multi-contact plugs.
Strip away the bad experiences with the stupid multi-contact (+2, +4, Ir Fusion) designs, and you will find that those who have used Bosch plugs appropriate to the application have had very good experiences.
Bosch plugs are just fine as long as you use the type your car was designed for. I'd have no issue at all using their OE-style plugs if I needed some.
I think far too many people 'upgraded' to those +2 and +4 plugs from regular single-strap coppers or platinums, and blamed Bosch products in general when they had issues.
^^^This. Exactly.
If you read the posts in this thread, the people who say that all Bosch plugs are bad, or those who say that you should match the nationality of the spark plug to the nationality of the car (snort! really?) have no Bosch experience other than with the Bosch +2 or +4 (or, recently, Bosch Ir Fusion) plugs, or have been reading posts on internet forums where people had bad experience with Bosch multi-contact plugs.
Strip away the bad experiences with the stupid multi-contact (+2, +4, Ir Fusion) designs, and you will find that those who have used Bosch plugs appropriate to the application have had very good experiences.
Many cars can use alternative brand spark plugs with no problems at all.
But with Bosch, if the car did not come with them, don't use them.
Yes, they may work here and there, but the chance is not worth it.
We refuse to put them in in the shop, after so many various failures.
Bosch wires and components are otherwise very good.
This is the best advice to give.
But with Bosch, if the car did not come with them, don't use them.
Yes, they may work here and there, but the chance is not worth it.
We refuse to put them in in the shop, after so many various failures.
Bosch wires and components are otherwise very good.
This is the best advice to give.
Bosch Platinum is OEM plug for E430, when it was changed at 8x,xxx miles with another Bosch Platinum the original plugs looked like new. The replacement Bosch Platinum worked as well for 60k miles.
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