WienerWater

Just trying to find a consensus on best spark plugs for the "99 ML320, best performance and results.

springerfever

Bosch platinum 4.........do it yourself !!

WienerWater

Thanks springerfever. I plan on doing it myself, since I work on all the cars I own. Th Platinum 4's, is that a general plug most people are happy with or just from your own experience?

springerfever

Before installing them in my 99ML430, I did some checking. Some seem to prefer the regular type electrode plug, but others had good things to say about the platinum 2's and 4's.

The plugs I took out with 75,000 miles on them were NKG and they were shot...the gap was way out due to wear. Good clean brown color but not much electrode left. With the Bosch P2/P4-s there is no electrode to wear. If you're going to leave the plugs in for high mileage, I would recommend them......

Plan on about two hours for the job and remove the coil packs/air cleaner housing/etc. the more room the better. Some WD40 will come in handy to help loosen the boots and I believe it was a 17mm closed-end wrench which helped remove the boots. Be careful with removal and installation and I would recommend using anti-seize on the threads for easier removal down the line.

There are some good helpful tips in this forum and others..check them out. One things for sure...no need to pay a dealer/mechanic 400-500 bucks for a job that is relatively easy.....even for a novice like me !!

springerfever

Oh, by the way.........the ML ran much smoother after the new plugs and no hesitation in acceleration up to redline in second and third. Gas mileage was up also, but only after I kept my foot out of it !!

WienerWater

Thanks Springer... I have a ton of knowledge and experience on cars (27 years) and have owned about 45 from classics to exotics. This is my first Mercedes. I have owned it since last August, but I do have a beautiful shop, all the tools including OBD 2 and engine analyzer/diagnostic machine (not bad for a personal garage). I have boot pullers etc, but have read about the 17mm wrench trick, will see what works best.
Thanks for the input, since there are so many personal experiences that have more value than any shop can tell you. The plugs are now about 41/2 years old (bought it second hand with 78,000km on it) but usually change them at 2 year intervals, no matter what. I am planning a long trip in May/June, so just want everything in perfect running order.
Thanks again.

55fanatic

would yall recomend these for the 5.5 engine? I have a ML55 that I plan on doing a tune up soon... It has 83k miles on it... Also would you consider a K&N intake in place of the stock airbox?

springerfever

55fanatic........man, that's a bad ride!! Love those bright red calipers!!

Lots of folks have nothing but bad things to say about the K&N filters. Many blame the K&N for gumming up their mass-airflow module that connects just above the filter housing. This little item is pretty pricey; haven't had to replace one but I think they are about $200.00.

That being said.........I use the K&N on my ML. I've had it for about a year now and absolutely no problems. I occasionally take it out and tap it and clean out the housing and it sure beats replacing the paper one on a regular basis. I have yet to use the cleaner/re-oiler for the filter and I believe thats where folks get into trouble.....they over-oil the filter and that leads to problems with the MAF. I think the K&N is a great filter but be warned, many think its nothing but trouble. Caveat Emptor !!

The plugs are also a personal choice. Shoot, if you don't like the Bosch, takem out put in regulars and you've still paid less than having the dealer do the work. Or start with the conventional plugs.

ah..all the choices !!!

LiquidSmile

I was looking to do the plugs on my ML 55 As well. I'll be hitting it up this weekend.

55fanatic

Thanks, I love her... Im hoping I get to keep her long enough to get to give her a good tune up... well see what my insurance company has to say about all the broken powertrain parts because of my accident... Im hoping it will all be taken care of...

sashatai

I went to my MB dealer for a 70,000 mile check up and they wanted to charge me $500+ to change my spark plugs....I said "that seems kinda high for spark plugs" and she said "well that includes labor"...I said..."I'll pass thanks"..I've looked on-line for those bosch platinum 4's and the most expensive ones I saw were like $8 a piece...how many do I need for a 99 ML 320?

straightSIX

2 per cylinder= 12 plugs

cyeung65

I am very happy with the Nippondenso Iridums IK16s. A bit pricey but well worth it. I changed them out by myself at 30K miles and it made a significant difference in throttle response and gas mileage (up about 1 mpg on highway).

55fanatic

I changed mine with the Bosch about 1000 miles, also swapped out three coils... and my truck runs 1000x better... Its great I gained almost 2 full miles per gallon, mine were changed at 91k miles. Im also going to try changing the fuel filter soon and prolly gonna get a green filter!!!

old98

I am new here so cut me some slack, I was looking for info on my ML, I am a DIYr, I just put plugs in my 98 yesterday in about 90 minutes, but I did it a little different than over the fender, when I was changing the front struts a few months ago I noticed the plugs were easy to get to when you have the inner fenders off, so I took off the wheels, removed the 6 nuts that hold the inner fender off, and heat shield on drivers side held on with 3 nuts, used a plug socket, a u-joint and a 18" extentinsion and a flex head ratchet, I put in bosch plat. 4, anti seized them. I paid $5.99 per plug at a local parts store. The original Boschs had 135,000 on they and still looked OK. but, I do think I am getting 1 more mile per gallon in just the first day. I hope this helps someone, We can keep these things running.

springerfever

old98

Welcome to the forum. All kinds of great information here. When I changed my front shocks a few months back, I removed the liners and also noticed how great the access was to the plugs. I've still got quite a while before my next plug change, but that's definately the route I will take. By the way, I've got over 230,000 on my 99 ML430 and they are definately built to last if you keep a close eye/ear for problems.

I fear I'm about to pay dearly (500.00-800.00 estimates) to replace the original water pump. One of the independents that gave me a bid said there are 22 bolts holding the water pump in a range of sizes/lengths. I told him I might tackle it on my own and he said it wasn't too bad, just make sure when you remove a bolt put it in the same location on the new pump so you don't get them confused !

Keep us posted with your projects and shoot us some pictures !

Stiggs

I thought you guys would get a kick out of this :

My 1999 ML430 is in the shop for a B-service right now. It has 63K miles on it. The dealership says I should replace my spark plugs every 5 years. So I ask them how much. Ready for this........$1,200.00. Hand to God thats what the woman said. I was speechless. Needless to say I told her no. I think I will go get me some of those Bosch platinum 4's. When I go buy them is there any special size or number I have to get. I've never purchased spark plugs before. I think from previous posts that I need to buy 16 plugs (2 per cylinder). But is there a special part number?

I know I will get away alot cheaper if I buy them myself and have the local guy down the road change them.

Ron in SC

Use only MB recommended plug to avoid damage.

See thread below.

http://www.mercedesshop.com/shopforu...ighlight=plugs

yetis

Ron, you don't happen to live in Ansonborough?