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HEMI Spark Plug Change....What an easy job! :D

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16K views 49 replies 28 participants last post by  RobinVA  
#1 ·
Just changed all 16 plugs and it was the easiest job in the world to do. Just make sure you blow out the area around the coil and the tubes before removing the old plugs.

I used Antiseize and torqued them to 15 ft lbs which is not very much at all. I think the old plugs were in there a lot more than that but could be just because they were in there for a while and a little seized in and dry. They squeaked when they were removed.

But again I state, what an easy job to do. Plugs cost me CDN$30 on sale. Took me longer to pull the 6 plugs out of my Blazer than it took to do all 16 on this HEMI. I love this car.

I also removed, cleaned and reinstalled the PCV valve and cleaned the throttle body.

The throttle body was a MESS, the front is fine, but the back had a layer of crud on it that was easily removed with throttle body cleaner, a toothbrush and a rag. About 2 minutes and it was clean as a whistle.

I just can't believe how easy this car is to work on. :fing02:

I forgot to replug in the IAT sensor on the intake and I got a check engine light. Pulling the #11 fsue for two minutes removed that.

Do I have to relearn the windows, Stability control and the MDS when i remove the #11 fuse?
 
#4 ·
Great question!

385000 miles

The plugs were not that bad at all. Most of them were 0.048 - 0.050 and a couple were 0.052. On plug had oil on the threads from a light seep from the plug tube seals but from the looks of the oil it has been there for a long time and there was very very little oil on the top portion of the threads.

Not bad at all really. The idle sure has smoothed out.

Man, that throttle body needs to be cleaned at least every 20,000miles.
 
#8 ·
Changed my plugs about a month ago. It was so easy a caveman can do it. lol. I replaced mine with bosch platinum 4's. Nice plug. 4 times the spark. Only thing is that the plug is 6 bucks a pop, but well worth it.
 
#21 ·
Why did you change your spark plugs so soon? I didn't think they needed changing that fast?
Just on the 5.7. They come with 16 OEM single electrodes and are not indexed (electrodes pointing away from the exhaust valves). Chrysler advises changing the plugs at 30,000 miles.

The 6.1 engine uses a dual electrode plug, so the frequency of change is much longer.
 
#23 ·
Yea, don't believe the people saying it is the CAI causing it because it isn't. Filter oil doesn't cause those kind of deposits anyways especially only on the back side of the throttlebody.

It is the PCV blowby causing it. Might be a good reason to put a PCV catch can on this engine and take that stuff out before it gets a chance to go back into the engine though.:fing02:
 
#27 ·
Plugs

I bought a set of Champions at Pep Boys a few weeks ago for $1ea. I just changed plugs in my other car, an 07 Mustang GT, and the lowest price Champion plugs (platinum) for the Mustang were $12.95 ea. NAPA's price was $20 ea. The metal body of the OE plug is a 2-piece design, and the lower portion can sieze in the head due to carbon build-up and separate when the plug is removed. I didn't have that problem, but when it occurs, the stuck piece has to be removed with a $200 extractor, or worse case, the head may have to be removed. Champion is the only source for a plug with a 1-piece body design, and the distributers are gouging us as a result. The OE plugs are 100,000 mile platinum, but everyone who knows about this is changing early to avoid disaster later.
 
#28 ·
hey northern, what store did you get yours from, I think its time I replaced mine. Do they still have a sale going on? Which plug should I go with for the 5.7?
 
#29 ·
Go with the Champion, as the manual states. DO NOT USE PLATINUM. There is quite a few posts about this matter, so you should probably do a search. From what I remember, the platinum, while they do last longer, do not conduct the same amount of juice the copper (Champion) do. That's why our engines need the Champion and cannot use the platinum long-lasting ones like the other Chrysler cars. They cost alot less, but need to be changed more often, so it sort of balances out in the end.

But do the search and read the specifics.
 
#31 ·
#33 ·
Imo

It should be noted that many members run platinum and iridium plugs in their 5.7 Hemis.

They run fine. With no problems. Seems ok seeing as the 6.1 comes with them from the factory and asks for service at 100,000 miles.

The only reason there's 16 copper plugs in the car from the factory is price. They're cheap.

The only reason to use a different plug would be to get longer plug life, but due to our "waste spark" ignition that reverses polarity you'll need a double platinum or iridium plug. These are expensive, but some people don't want to change their plugs every 30K!
 
#34 ·
The 5.7 and the 6.1 both use 16 plugs, but the SRT puts in platinum and the 5.7 copper. Why would they consider price for one and not the other? Could it be that it is the MDS requires the copper (el-cheap-o) plugs for a particular reason? I would be interested in learning if the 5.7 in other Chrysler applications calls for copper plugs as well.
 
#35 ·
volume

The 5.7 and the 6.1 both use 16 plugs, but the SRT puts in platinum and the 5.7 copper. Why would they consider price for one and not the other? Could it be that it is the MDS requires the copper (el-cheap-o) plugs for a particular reason? I would be interested in learning if the 5.7 in other Chrysler applications calls for copper plugs as well.

The SRT division is allowed much more flexibility as their cars are sold at premium prices and are way more profitable to Chrysler. The regular Hemi is a very large volume piece and as such is subject to more cost restraints. The cost difference is quite considerable.

I just watched a 5.7 Charger R/T owner putting in new "high end" plugs and they run just fine. No problems at all. MDS is unaffected.
 
#40 ·
Yes, the 5.7 has an EGR which runs into the manifold right behind the throttle body. Not sure if the 6.1 have one (don't think so, but the SRT owners would know for sure).

What difference would that make?
 
#42 ·
Glad to hear it's an easy job. My 06 Magnum is coming up to 50,000K and my dealer service center has reminded me that I should book it in for that service. They're planning to charge me over $700 for changing the plugs, cleaning the throttle body, and decarbonization...whatever that may be. If anybody has any idea what they plan to decarbonize, I'd appreciate the insight.

Thanx
 
#43 ·
Awesome information!!! I am doing my mine as soon as I get off of work. I am going with Champions. Maybe some pictures, with a quick how-to will follow. Thanks for the info!!!