I am about to change the plugs in my 1999 Dodge Ram Van. It has a (5.2) or 318 engine. I have been reading about different spark plugs and I am looking for what would be the best plug to put in it based on durability and I am hoping to get a 1 or 2 increase in mileage. Right now I am getting about 14 miles per gallon on a good day. Realistically I only expect to get about 16 mpg when i am done.

I have not changed the plugs in this van since I got it from my uncle and drove it back from California. So as far as I know these plugs have been in this engine for a very long time.

The plugs I am looking at are Bosch Platinum Fusion which are very expensive, Denso Iridium if I can find them, NGk Iridium if I can find them. All of these are very expensive plugs. There is also the option of just using the original style OEM copper style plugs.

In the old days, we used Champion in Dodge, Autolite in ford, and AC Delco in Gm products. NKG, Denso and Bosch were plugs used for imports.

Thanks,
Jason

 

I decided to go ahead with the Bosch Fusion plugs. I found out there is a rebate and they have a money back guarantee if I am not happy with them. I had purchased a set of Wells electric sparkwires, but decided to return them and purchased a premium set of Bosch wires instead. I used a Borg Warner Cap and a Accel rotor.

I was able to work within the heat shields that surrounded the plugs without removing them. I had a little difficulty with the two plugs in front on the drivers side until I remembered I had thin walled deep well socket. Once I used that socket the rest of the tune up went smoothly. I ran a thread chaser down all the spark plug holes except for two. I also used anti seize on all the plugs during installation.

The inside of the old distributor cap had score marks on the contacts. The rotor was also pretty well shot. It was amazing the van was running as well as it was.

After finishing up the work, I started the van up and it was running smoother than it has ever been. I filled the tank up and we will check the mileage over the next few days.

I have a couple of things left I need to do before I am finished with my mechanical repairs. One is fixing the rear end which I have mentioned before. My personal belief is that it needs a ring and pinion gear replacement. My local dealer said they would charge $500 including parts so I am going to let them do it. I know it would cost me that and probably more to swap out my rear end with one out of a salvage yard and then I would not really have warranty.

The other thing I have to do is replace the drivers side window regulator that recently went bad.

Jason

 

I am using the NGK's and so far I am liking them. Much better than the OEM Champions.

 

Thanks for your response. The plugs I pulled were the Autolight 5224 if I am remember right. I think those are basic copper core.

The new Bosch fusion I put in seem to fire and run well. As I mentioned I installed New Premium Bosch wires as well as an Accel rotor and BWD distributor cap.

I do not know if the computer completely adjusts the timing, but it seems my van never wants to start on the first turn of the key. Of course in my experience, the dodge vehicles I have dealt with in the past never seem to start with the first turn of the key. I still have an old timing light so I am going to investigate my shop manuals and see if its worth while to throw it on the engine and do a small adjustment in the timing. Of course if the computer adjusts this automatically it might be a big waste of time.

Once the Van starts, usually on the 2nd or 3rd try, it runs very smooth and well. While I would love for it to start on the first turn of the key, I might be better to leave well enough alone.

Do you have an experience or opinion on this? Should the Van start on the first turn of the key or is it normal for it to take two or three tries?

Oh and before someone asks, I do try to keep the tank at least half full and how the van starts does not appear to change whether the Van is full, half full, or 1/3 of a tank.

Jason

 

My 2000 with 5.2 Magnum engine starts on the first try in any weather with 1 to 3 seconds of cranking. It started this easily even with bad distributor cap, bad wires and old spark plugs back when I first got it. If I remove the battery cable and reset the PCM then the first start seems to take 3 to 4 seconds of cranking.

Try this: turn the key to "on", but don't rotate it to "start" until you hear the pump stop ( meaning the fuel line is fully pressurized ). Now try to start it, it should start within 4 seconds.

And to answer your first question, I prefer the plain Autolite copper spark plugs. They last nearly forever and I've never had an issue with these in any vehicle.

 

Yes I do have experence on this. Do as the previous fellow suggested and if that does not work then try cycling the key on till the pump stops and turn the key off then right back on about 3 times. Then start the van. These may help on a faster start or may not.

What the problem is the check valve in the fuel pump module. The check valve is not holding pressure. There is a after market check valve that you can buy and install on the fuel line but a problem is that the fuel lines are nylon and can be fun installing them onto the check valve. Plus it is an extra place for a potential fuel leak. Personally I recommend just replacing the fuel pump module.

Also as you stated the timing is computer controlled.

 

As for plugs, the Autolite AP5224 are the single platinum types that do the job very well. If you then take the plugs and side-gap them, the spark is more pronounced to burn the fuel completely. This effect is just as good in performance as any of the leading Iridium plugs without spending top dollar.

The real question then to ask is, what ignition wire set was used and did you get a copper/brass contact cap-n-rotor? Dodge also has a TSB out for the proper layout for the ignition wire routing. Following that will ensure a good spark for better MPG.

As for plugs giving you 1-2mpg better, that's only if the old plugs got burned up and were failing. If not, then not much would be seen.

A TB mod of grinding down the front two walls on the MAP sensor side has a good effect towards MPG. Running with a higher load range tire without the side bulge will help greatly. Repacking the front bearings with a synthetic bearing grease will help greatly. Replacing the rear fluid with the Redline 75W90 synthetic will help greatly (also a Chrysler/Mopar TSB for better MPG), ... Look up my thread on IMPROVED MPG.

 

Thanks Steve,

I will let you know how the plugs do soon. I think it will take a tank of fuel or two before I notice a difference in mileage. As you might be aware, I have needed to repair the rear end since I got this van. Currently it is at my dealer who pulled appart my rear end and discovered what I thought was an issue all along, problems with the pinion bearings.

The following is a list of what we are replacing:

1 Inner Pinion BRG Kit
1 Outer Pinion BRG
1 Outer Pinion Race (Race was scored) I suspect this was from sitting 3 years +
1 Crush sleeve
1 Pinion seal
1 Pinion nut
1 RTV (for gasket)
2 Fluid (coming from Chrysler dealer which should meet the TSB) Synthetic

Total for parts is $238.41

If I buy a rear end out of my local salvage yard or have one shipped in, I only get a 90 day warranty and have to spend about $800 on avg for the rear end which could have high mileage. In addition to that I would have to pay at least $200-$300 for the swap. I can do it myself but it just does not seem to be the best decision.

Deciding to do things this way I get mine rebuilt with new parts and I get a 1 year warranty. Also the dealer does the work and it seems to come out to be slightly less expensive.

Now after I get the rear end done, I think I will be able to report back more accurately on mileage and performance. The wires are premium Bosch wires sold at Auto Zone. They were put on using the existing wirelooms and following the existing pattern. So far the engine appears to run smooth. The Van will be tied up until at least after Tuesday getting the rear end repaired. As soon as its done I will report back. I also received the window regulator today to replace the one on my drivers side window.

My finance and I are getting married Sept 5th. We are driving down from Illinois to Florida so we should be able to give a good report on mileage, the Bosch Fusion plugs and wires.

Steve the cap was changed with the wires and I used a BWD or borg warner cap with brass contacts that I purchased at O reilys. The rotor is an Accel I bought at Auto zone.

Thank you black van and Mobile. I normally wait until I hear the pump stop and see the lights go off and then try to start. I have not attempted to cycle the key yet.

Jason

 

Steve, doing the TB mod of grinding down the front two walls makes me nervous. I will read through it again and give it some thought. This is a 318 with a 355 rear end so the most I expect out of it is about 16mpg. If I happen to get more I would consider myself lucky.

Jason

 

Removing the air horn should not hurt anything. Truth is , the manufacturer only added an air horn to reduce the sound of air rushing through the carb/tb. In the old days it also supported the choke but this is no longer relevant. I don't think removing it will change mpg much but racers do it and it should improve throttle response and top end hp. Steve's tips are all valid and I recommend them.

And congratulations! and I certainly hope your trip goes smoothly and without incident.