For the past few months I've been reading a lot about these plugs and they look like a good idea. In the engine section there are some good messages about "side gapping" plugs that make sense and make the plus 4 plugs look even better.. Changing plugs and wires on older vehicles with a lot of mileage will always cause a noticable improvement. My question is for the readers with newer vehicles, say less than 10K miles, who have switched. Did you feel a difference? Did your mileage improve?

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98 Nascar Edition, Superchip, Airaid, Flowmaster 70 series, bedliner, in bed tool box, Profile bug deflector and window vents, Class III receiver hitch.

 

I'll let you know. Planning on doing them this weekend. I am at 45K now so I am more sure they will for me. Bosch says they will pay for em if you don't notice the difference!

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97 F-150 SC Lariat, Styleside, White over Gold, 4.6L (Windsor), Automatic, 3.55 rear end, electronic 4X4, w/ every option of Lariat and ORP packages except the 17" wheels and the 4X4 decals, MODs so far: K&N air box mod, Gibson Super Truck, clear Bugflector II, Leer TSC 600 hard cover, Bridgestone Dueler OWL ATP 265/75 R-16's, TrailMaster Invader N7 shocks, Smittybilt step bars, Ford moulded mud guards, "White-white" head lamps.

 

cphilip, thanks for the reply and the info on where to order. My wife has a 90 Chev. custom van with only 48K miles. It runs great, did belts hoses and air cleaner last year, but I know the original wires and plugs need to be replaced so I ordered them yesterday from Auto Medic. The Plus 4 plugs do have a different part #, 4449. The Bosch wire set was $29.20 shipping included, which I thought was a decent price. I let you know how they work on the Chev.

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98 Nascar Edition, Superchip, Airaid, Flowmaster 70 series, bedliner, in bed tool box, Profile bug deflector and window vents, Class III receiver hitch.

 

Wow, $29.20 for a Bosch wire set. Was this for a V8? Have you heard anything, good or bad, about their wire sets? Anyone?

 

Yes that was for a 350 v8. I know nothing about the Bosch wires but hope they are as high quality as their plugs. The price is about the same as a cheap set at parts stores. I'll throw out a knew topic on Bosch wires.

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98 Nascar Edition, Superchip, Airaid, Flowmaster 70 series, bedliner, in bed tool box, Profile bug deflector and window vents, Class III receiver hitch.

 

Great. Do it I will follow. Yes that is way too cheap huh?. But them Germans usually make very good stuff.

Hey, I know how they must a done it. They probably hired all the laid off third world country poor bas*urds that Kathy Lee Gifford fired and put em to work makin wires?

 

BOSCH makes all kinds of great products. Their tools are fantastic. As a matter of fact, I even have a BOSCH dishwasher in my home It works great too. Hopefully their wires are as good as the rest of their products

 

I installed the Bosch +4 plugs in my 1988 Mazda MX6 GT Turbo. The car has 50,000 original miles with plugs being replaced 6 years ago at 35,000 miles.

I replaced the wires and plugs and nothing else. Over the past two tanks I have averaged a 2.5 mpg increase. That's pretty incredible since the old plugs weren't really in bad shape. Performance is about the same, however, cold starts are much quicker and somewhat smoother.

I'm looking forward to adding them to my F150 in the next few weeks.

So far I give the Bosch +4 plugs a thumbs up.

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"Baby Huey" (Big Round and Loves to Eat gas) aka '98 F150, Auto, 3.08 axle, Blaupunkt, SuperChipped, Oil Stain on Seat from Service Tech at WalMart, Small Dent on passenger Door from "soon to be deceased" co-worker.

 

Personally, I have had good luck with the Bosch Plus fours myself. Because of my 60 mile round trip drive to work, I recently purchased a 1992 Eagle Talon with a 2.0 DOHC engine and 5 speed manual transmission. At 26 Miles per gallon the car was fairly effecient as a daily driver. Especially when compared to the 9MPG my F-150 gets. 2 weeks ago I installed Bosch plus 4 plugs in the Talon and am happy to report a 3MPG increase to 29 MPG. I have however tried these plus in conventional V-8 engines (5.0L ford) with no additional increase in mileage or drivability. My theory on this is that with the DOHC engine your plug sits directly above the combustion chamber in the center of the valves. With a conventional single electrode plug the electrode its self "blocks" the chamber from direct spark. With the plus 4 design in that style engine not only are you opening up the spark contact, but you are also giving the energy aditional grounds. In a conventioal engine I have had better luck indexing standard plugs. Oh yeah and you Modular guys. (4.6&5.4) If you are having a problem with a cyl 4 misfire. (P0301) make sure that the heater core coolant tube above the no 4 cyl is not leaking where it clamps onto the metal tube. This a very common problem. In addition if you have an air compressor blow out the plug holes before removing the plugs. Doing so has saved my countless hours. Happy motoring - Bill W

 

Yes.

 

Wow, this is a really old post I put up 4 years ago under my original name. Just to update on the original question, I still own and drive the 90 Chev. Van. Have put about 20K miles on the plugs. Runs fine but no measurable improvements in mileage or performance.

 

I have had a set of Bosch Platinum +4’s in my 5.4L for over 15,000 miles now. The most noticeable difference after the install was with the throttle response. The most unexpected benefit of the install was an ultra clean emissions test, and in my state your OBDII computer and tailpipe emissions are tested when your vehicle is running on a dynamometer.

 

no they dont work well on fords !!!stick with motocraft and by the way aint this a ford site??????????????????
i dont want to here about eagle talons hondas or any other rice burner unless its about smoken thouse lawn mowen sounding cant afford a real tire smoken f150 5.4l V_8_ 320 hp dyno proven eaten civic poopen toyota hot roden man truck!!!

 

^^^ There are rice burners that have more money stuck into them than your "expensive" truck... oh yeah, they would whoop you too, 320 whp isn't THAT much.

I don't mean to knock Ford, but there is always a guy out there that has a faster car than you - even if theirs is Japanese.

 

LMAO! Dudes y'all crack me up.