Running rough after spark plug and wire change.

[MotorCityFats13]

I been wanting to change my plugs for ***** and giggles since I dont know if they are stock or not... sounds like this is much more easy than a 2nd gen... where the last 2 on the passenger side need some wheel well mods to gain access to the plugs.... and I am not surprised that the bosch plugs were garbage... I have not used them since the early 90's and those were bosch 4's on a very primitive ignition system.... 1979 jeep CJ7 304 V8 and 2 years later switched to accel U grooves.... I did autolite plats on 97 ranger and 98 explorer 4.0's.... never had a problem... on my 99 f-150 5.4 I had to look really hard for some autolite coppers in a cooler range because I added a paxton novi 2000 and never had any problems

 

[Explorer75]

It´s too bad that Bosch plugs a have bad rep. I´m actually using Bosch and find them a lot better than the Motorcraft SP-412. Before you think I´m crazy this Bosch plugs aren´t the ones that usually give trouble like the +2 and +4 kind. This are called OEM Fine Wire Iridium

http://www.rockauto.com/catalog/moreinfo.php?pk=3153432&cc=1444725&jnid=498&jpid=15

They come pre-gaped at 0.052" and have a 7 year warranty. This plugs almost cured the horrible idle this engine is known for, give better mpg and have an overall better and smother acceleration. When I got them they all came perfectly gaped and all the same. If the OP got this type as they also come in platinum maybe they were dropped or poorly packed and the gap was tampered. When I got the SP412 they were all over the place but within specs (between 0.052 and 0.056).
I have tried a lot of spark plugs and can vouch for this BOSCH 9660 to be the best for this engine. Just to be clear, I´m in no way associated with Bosch, Rockauto or have anything gainst Motorcraft products...

 

[portedav]

...This are called OEM Fine Wire Iridium

http://www.rockauto.com/catalog/moreinfo.php?pk=3153432&cc=1444725&jnid=498&jpid=15

They come pre-gaped at 0.052" and have a 7 year warranty. This plugs almost cured the horrible idle this engine is known for, give better mpg and have an overall better and smother acceleration. When I got them they all came perfectly gaped and all the same. If the OP got this type as they also come in platinum maybe they were dropped or poorly packed and the gap was tampered. When I got the SP412 they were all over the place but within specs (between 0.052 and 0.056).
I have tried a lot of spark plugs and can vouch for this BOSCH 9660 to be the best for this engine. ...

These are exactly the BOSCH plugs I used. Like said in one of my earlier posts, gap was inconsistent between the six plugs and the average was 0.050". Can confirm came packed in original packaging, with paperboard sleeve over the threads and electrode, and no dropping (at least by me). Glad you are having a better experience.

David

 

[Explorer75]

These are exactly the BOSCH plugs I used. Like said in one of my earlier posts, gap was inconsistent between the six plugs and the average was 0.050". Can confirm came packed in original packaging, with paperboard sleeve over the threads and electrode, and no dropping (at least by me). Glad you are having a better experience.

David

Thanks

If they were the same I find it really odd they performed that way. Something was really out of spec. You can do a search at amazon and all this new type of Bosch OEM spark plugs have very good reviews, other part numbers that fit other Ford vehicles have 4.5+ stars and people are very satisfied with them. Then again I guess nothing beats OEM parts in terms of reliability, maybe my results aren´t common. Bottom line, it´s great that you resolved your issues with the original part.

 

[portedav]

...this new type of Bosch OEM spark plugs have very good reviews, other part numbers that fit other Ford vehicles have 4.5+ stars and people are very satisfied with them...

Exactly why I picked them to begin with...reviews are just as good at the auto parts stores. Trust me, I was just as surprised as you.

Thanks for reading and replying!

David

 

[BootyDo]

Glad to hear everything is fixed and running smoothly! I had a bad coil on my 8th cylinder years ago and I remember the feeling when I finally swapped it. It was like I some insane demon crawled in my engine bay. Whole new ride!

A little off, but regarding spark plugs in general, has anyone ever had experience with the Autolite Double Platinums?
http://www.amazon.com/gp/product/B000CIJN9Y?psc=1&redirect=true&ref_=ox_sc_sfl_title_2&smid=ATVPDKIKX0DER

Their site doesn't even list them for the truck but I'm curious how they might perform compared to the Motorcrafts given their prices.

 

[Flag Gibby]

Double platinums are what originally came on the V6 so they should run great with the waste spark system of the V6. I personally run NGK finewire double platinums since I could not find a compatable double platinum other than the NGK's way back when I did mine.

 

[Explorer75]

Glad to hear everything is fixed and running smoothly! I had a bad coil on my 8th cylinder years ago and I remember the feeling when I finally swapped it. It was like I some insane demon crawled in my engine bay. Whole new ride!

A little off, but regarding spark plugs in general, has anyone ever had experience with the Autolite Double Platinums?
http://www.amazon.com/gp/product/B000CIJN9Y?psc=1&redirect=true&ref_=ox_sc_sfl_title_2&smid=ATVPDKIKX0DER

Their site doesn't even list them for the truck but I'm curious how they might perform compared to the Motorcrafts given their prices.

Just to be sure for the V8 you need another spark plug. Also the one you in your link is for an earlier version of the 4.0 V6, the 2006-2010 has a projecting tip, so this is the one that should be used
http://www.amazon.com/Autolite-APP5143-Double-Platinum-Spark/dp/B006ZLGKSE
Not enough and too expensive, but the correct part. I think it´s been phased out because when I was searching for a spark plug I wanted to try this one but no one had them, only amazon (too expensive and just 2).