Changing one spark plug on my van (will do the other 5 some other time)
Difficulty Level (Easy, Medium, Hard, Insane):
Medium
Process:
A couple of weeks ago I started getting a check engine light on my 2011 Dodge Grand Caravan. After I scanned it I got a "P302 - Cylinder #2 Misfire". I was just going to ignore it but then I noticed that my fuel consumption went up from about 14L/100km to almost 17L/100km so I figured I'd better have a look at it.
After some research I learned that the P302 could range anywhere from a bad spark plug to fuel injectors having to be replaced. Before I decided to go out and spend another night in the shop working on my van I'd call the dealership to get a price. I couldn't believe it! They wanted over $300 bucks to replace 6 lousy spark plugs. To add further shock to my system, they wanted $22 bucks PER spark plug. Luckily I found some nice Iridium plugs at Napa for $15 bucks.
At first I was going to replace all 6 of them (which really, I should have) but decided just to try the one and see if it would make a difference. I am glad to say that it really just was the spark plug that caused the check engine light and replacing the #2 cylinder plug fixed the issue.
Whenever I get a new vehicle, the first thing I do is get a Haynes manual for that particular vehicle because taking paying $20 bucks once per vehicle is a lot cheaper than having to replace parts that broke during dis-assembly because I didn't know how to take it apart.
The job seemed daunting at first because I had never done it on this vehicle, but now that I've actually done it, I could probably do all 6 spark plugs in about an hour's time.
The steps were something like this:
1. Take off the air filter & housing (4 clamps)
2. Take off the engine cover (snaps right off)
3. Take off the resonator (snaps right off)
4. Unplug the electrical plugs (3 or 4)
5. Unhook various hoses (3 or 4)
6. Remove the upper intake manifold retaining bracket bolts (1 bolt, 2 nuts)
7. Remove the upper intake manifold front nuts (2 of them)
8. Loosen the upper intake manifold center bolts (7 of them)
9. Remove the upper intake manifold
10. Remove the ignition coil plug
11. Remove the ignition coil bolt
12. Remove the spark plug
Installation is reverse of removal
Update:
Unfortunately, the check engine light came back on a couple of days later with the same P302 code. After some more research I found out that apparently there was a very well known "#2 cylinder misfire" issue with thousands of dodge vehicles affected. It looks like the cylinder heads for some 2011 models (3.6L pentastar engine) had a design flaw which results in cracked cylinder heads and P302 errors.
I brought it to the dodge dealership to have it verified and they confirmed that this was the case with my van. It is currently in the shop where they're replacing the cylinder head (under warranty).
I'm so glad that dodge extended their warranty to 139,000km or to the year 2021 whichever comes first. Saved me a LOT of work there. I asked the service guy what this would have cost me IF it wasn't under warranty and he said about $1200 in labor plus about $800 in parts...Easiest $2,000 I didn't have to spend ever!
Pictures:
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| Right at the beginning before starting |
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| The cover is off |
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| After removing the upper intake manifold (7 bolts) |
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| Another view (you can see the 3 front ignition coils - #2, #4 and #6 from L to R) |
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| Covering the holes with a clean rag |
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| After the #2 and #6 ignition coils were removed |
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| Comparing the old with the new spark plug |
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| Close-up of the new spark plug |
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| Close-up of the old spark plug |
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| The engine as it was Friday night in the dodge dealership |
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| The service "bill" of $0 (no charge - n/c) |
Socket set
Screwdriver
Wrench set
Channel lock pliers
Work light
Materials:
1 spark plug
Cost:
$15.00
Time:
2hrs
Savings:
$285.00
Conclusion:
Worked like a charm
