Recommendations on Spark Plugs

[1985xjlaredo]

Another spark plug thread!!!1!

 

[blackdoutxj]

Any plug but BOScH I ran them in my wrangler and had nothing but problems. The check engine light always came on and when starting sometimes it would back fire threw the throttle body. I like NGK myself

Really?!? i have ran bosch platinum plus's for 3 years now and i like them a lot... i just got some fresh ones in there today..never had any problems with them either

 

[wolfpackjeeper]

the platinums are an OK plug. Most people have problems with the +2 and +4 varieties. The only thing those run well in is a honda.

 

[REWSTER]

any one ever use motorcraft plugs?

 

[wolfpackjeeper]

pretty much any coppor spark plug will do fine. This is not a picky engine.

 

[FlexdXJ]

anybody here ever replaced their spark plugs?

No i haven't! i just have champions in mine. nothing special just OEM replacement.

 

[Muddyjeep36]

Really?!? i have ran bosch platinum plus's for 3 years now and i like them a lot... i just got some fresh ones in there today..never had any problems with them either

The check engine light was always coming on and the code was intermitent misfire. I'am a mechanic for a living and some of my mechanic friends ran into same problem. Since I pulled them out about 4 years ago I have had no problems, plus better power and fuel mileage about 2 miles to a gallon. They where the plat 4s.

 

[blackdoutxj]

The check engine light was always coming on and the code was intermitent misfire. I'am a mechanic for a living and some of my mechanic friends ran into same problem. Since I pulled them out about 4 years ago I have had no problems, plus better power and fuel mileage about 2 miles to a gallon. They where the plat 4s.

oh ok!! i work at kragen, i was very unsure to run the +2's or +4's i just like the single electrode plus's i never had a problem with em! but to each his own!

 

[bchulett]

Autolite.

 

[gradon]

So I have had the rc12s in for two days now and the 4.6 does not like them--occasionally bucks and last night wouldn't rev past 3K when I got on it(surge)--dunno if I should fool with the gap. Pinging was almost non-existent in the 2.5K-3K area, the area that the rc9s had some during part throttle accel. I should've tried out the NGKs, based on your recs(Wolf and Talyn can be a lil sketchy you know, jk), but had to see the difference b/t the 9s and 12s. Before the 4.6, the 96 4.0 did well with autolite double plats.

 

[88 Wagonman]

So I have had the rc12s in for two days now and the 4.6 does not like them--occasionally bucks and last night wouldn't rev past 3K when I got on it(surge)--dunno if I should fool with the gap. Pinging was almost non-existent in the 2.5K-3K area, the area that the rc9s had some during part throttle accel. I should've tried out the NGKs, based on your recs(Wolf and Talyn can be a lil sketchy you know, jk), but had to see the difference b/t the 9s and 12s. Before the 4.6, the 96 4.0 did well with autolite double plats.

There used to be an engine rebuild shop (actuall they were called Engine rebuilders) that I used to warn people about before they went out of business that would used spark plugs like that, you know, "heat range doesn't matter, just put in whatever fits in the hole."

 

[wolfpackjeeper]

I went with the v-power heat range 5 this last time around, seems to be about right for my build. We shall see when I pull them next time and see what color the ceramic is.

 

[Talyn]

So I have had the rc12s in for two days now and the 4.6 does not like them--occasionally bucks and last night wouldn't rev past 3K when I got on it(surge)--dunno if I should fool with the gap. Pinging was almost non-existent in the 2.5K-3K area, the area that the rc9s had some during part throttle accel. I should've tried out the NGKs, based on your recs(Wolf and Talyn can be a lil sketchy you know, jk), but had to see the difference b/t the 9s and 12s. Before the 4.6, the 96 4.0 did well with autolite double plats.

Whats your current gap? IIRC if you are missing at higher RPMS you need to close the gap up. Also, from what I have read you need to close teh gap a bit for higher compression.

 

[wolfpackjeeper]

yea, generally higher compression you need a smaller gap, and a slightly colder plug.

 

[gradon]

I went with the stock .035" gap on the 12s. A few days earlier I tried closing the 9s to .030" and that helped the 2.5-3K range some. I kept those plugs and they're still good, so I'll swap them back in for now. So what are the colder ranges of the ngks? And range 5 is how many below the stock one?

 

[wolfpackjeeper]

I think it is one step below stock.

We ran the part number and came up with the 6 as the stock heat range.

 

[tomhil]

Ive had problems with all kinds of plugs. The E3 plugs are the only ones I'll run now. It runs so much smoother then any other to me.

 

[wolfpackjeeper]

the lawnmower plugs? Honestly other than in the package they sell from quadratec the only place I have seen those is in the lawnmower aisle. No offense, but I consider them another gimmick plug.

 

[gradon]

Has anyone seen a reddish tint on the porcelain before?

 

[Flyfisher]

I'm no expert, but did have an expert tell me once that the 4.0 can be sensitive to plugs. He's had lots of folks come in with runability issues...changed the plugs to the original stock Autolite plugs and problems go away. I've run them in my '89 4.0 without problems...and that's 270,000 miles. They aren't spendy either...bonus!