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Bosch Platinum +4 Spark Plugs

2906 Views 13 Replies 9 Participants Last post by  Warez
I am planing on changing my spark plugs and wanted to know if anyone has had experience with the Bosch Platinum +4 Spark Plugs. The guy at a local parts store recomended them but didnt give any particular reason other than "these are the best" and they are 5.99 a plug. It seems like they just have four electrodes instead of the three like on the stock plug and are made out of platinum.
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If you search past postings in this forum (keywords: bosch plugs) you'll find the +4's aren't widely recommended - the general consensus is to stick with the original single electrode type - I read the originals are also platinum. Hope this helps.
The bosch +4s are not good for you at all. Parts store guy gave me the same line years ago. I bought the +2s. I have since mailed them back to bosch and got my money back. They weren't worth the darn for me. The +4s are worse from what I have read. For the north*s, we use the dual platinum acdelcos. The center electrode and the ground electrode are both platinum.
My car came stock with 3 electrode plugs. I have the +4's in my car with no problems, but i have heard some stories....
Mine came with the 3 prong electrodes also. I think those are the stock plugs. I had changed mine to the +4, but when I did that the car started running terribly. I then figured out that the previous owner must've never changed the wires and that the extra current was too much, so I put the stock plugs and new wires in and the car ran fine. So if you haven't changed your $200+ wires in a while I would do that before I put the +4 in.
I just changed to the Bosch Platinum +4 Spark Plugs and have seen no difference so far. Nothing bad nothing good although I expect a few more miles to the gallon but still too early to tell. I did notice however oil in the plug wells not a lot but just enough to notice on the very top part of the threads of the plugs. The vehicele has 109,000 miles so i assume just worn piston rings but with this car it could be anything. Anyone else have this situation?
Mine had the three prong plugs and just put in the four promg plugs and runs great
I understand I have a different engine than you guys. But, for what it is worth, I had the +2s in for at least 15k miles. I thought they were fine at first. But then I started to experience problems. The main problem was one of the plugs acquired a crack in the ceramic shell. I decided to go back to the north*s oem delco plug. Going back to the delco after riding with the bosch's for a while allowed me to feel the difference immensely.
the catera come with bosch 3 prong and changing them to the four prong is not that big of a difference
The bosch +4s are the worst thing you can get if you look at the plug the four electrodes shoud the spark from the fuel-air mixture not good senses
The ground electrodes shroud the spark from the air/fuel mixture, not very efficient. Looks cool though.
Cosidering that the factory plugs are Bosche +3, I can't imagine how +4 would be a problem.
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