Rough idle after changing plugs...

[6G72Galant]

Ok, so ive been having a "Cylinder 5 misfire". Today, i decided to tackle the spark plugs myself. I unplugged ALL of the wiring sockets on the passenger side of the plenum. I removed all the bolts. Removed the coolant lines under the throttle body (i noticed there was a bit of slack in the TB cable, so ill address that later). When i removed the cylinder 5 spark plug wire, i noticed there was a considerable amount of oil there. If i remember correctly, i coulve sworn i saw 1 drop of oil fall down into the cylinder (spark plug was still in the cylinder). After removing the spark plug i noticed there was some oil on the first few threads of the spark plug. I know ill have to replace the O-rings. Ive heard that oil around the top of the spark plug boot is a sign of bad rings. So ill be replacing them.

However, after re-assembling everything. I took the time to make sure everything was connected correctly. I started up the car. And now it runs like shit. The idle is horrible. The car doesnt stall, but the idle stumbles alot in Park. You can actually see the engine jumping a bit when the idle stumbles (i replaced the motor mounts, so i know its not them). I drove to the advance auto to clear the CEL. I cleared it, and then it seems as if the car ran shittier. It even stalled on me when i was trying to leave the parking lot (waiting in Drive). Any ideas as to whats going on? I also noticed a crack in my intake manifold (not the top part, the lower part). Ill post pics of the crack later. Could that be the problem? Or did i disconnect a wiring socket that shouldnt have been disconnected? I distinctly remember unplugging a red and black harness on the passenger side. Should i not have?

As always, thanks for any suggestions and help.

BTW, i used these plugs...

http://www.ngk.com/glossary.asp?kw=V-Power&manID=1&pt=1

NGK Vpower. The iridiums werent available. And i needed to have my CEL off so i could pass inspection. i thought these would do the job. Could these plugs be the problem? Should i begin kicking myself in the ass now?

[Gtsnapper]

I had this problem a few weeks ago after changing the spark plugs and wires on my car, luckily I found a thread about it.

My Haynes manual show cylinder 3 + 5 cables round the wrong way on the distributer. Maybe it's correct for an older model.

I swapped them over on the distributer, and it runs fine.

I don't know if this is your problem, but good luck!

Edit:

Firing order for my 8G, on the distributer respectively:


4-------3

2-------5

6-------1

[6G72Galant]

CEL just came on again. Now ive got the code "Random/Multiple cylinder misfire". I think its these plugs i bought. When i tried x-referencing the part number, theyre not even made for the Galant. Theyre made for the Montero and Raider. Both of which have different engines. I dont understand how the hell the parts warehouse i got these plugs from concluded that they would work on my car. I called asking for NGK plugs for a 03 Mitsubishi Galant with the 3.0L V6 engine. The Galant doesnt even have these specific NGK's listed as an option. So how the fuck did they think these plugs were the correct choice for my car? Argh! Ignorance is annoying.

Heres the crack i noticed. Could this be causing that "sigh" sound when i turn my car off?
http://i71.photobucket.com/albums/i130/6g72galant/SDC11602.jpg

[6G72Galant]

I had this problem a few weeks ago after changing the spark plugs and wires on my car, luckily I found a thread about it.

My Haynes manual show cylinder 3 + 5 cables round the wrong way on the distributer. Maybe it's correct for an older model.

I swapped them over on the distributer, and it runs fine.

I don't know if this is your problem, but good luck!

Edit:

Firing order for my 8G, on the distributer respectively:


4-------3

2-------5

6-------1

Hmm...thanks for the suggestion, but i didnt remove or unplug any of the wires to the distributor. I did double check to make sure they were connected correctly. But I shouldve changed the plug wires along with the spark plugs. Ill be sure to do them when i change my plugs, again.

[pinoyesv6]

first thing i'd do is get some better plugs. those copper plugs u bought will only last u a few months, but since you're gonna be getting your hands dirty, might as well buy some platinum or iridium plugs and change them now.

and with that said, i'd go ahead and check everything once more.

[6G72Galant]

first thing i'd do is get some better plugs. those copper plugs u bought will only last u a few months, but since you're gonna be getting your hands dirty, might as well buy some platinum or iridium plugs and change them now.

and with that said, i'd go ahead and check everything once more.

Im def getting iridiums or platinums tomorrow. I have a feeling that the plugs i got were wrong. Thinking back, even the gap was off. In the repair manual (Haynes), its telling me the plugs should be gapped from .039 -.043. Yet when i had pulled up some plugs in the electronic catalog at advance auto, the NGK iridiums come pre-gapped@ .044. Ive used those same plugs before and had no issues with them. I shouldve gotten the same plugs again.

I also noticed the tip on the V-Power plugs is completely different from the NGK iridium plugs.

The V-power tips were similar to this... l\/l
Where as the iridiums were similar to this... /\

Im hoping this problem will be resolved by swapping in the iridiums. I need my inspection done asap:sad:

[RedGalant2k1]

You don't want to be using copper plugs in our cylinder heads. The copper and aluminum can metal bond over time causing a lot more issues than a cel light. The best rule of repair is ALWAYS first check what you just replaced.

[6G72Galant]

You don't want to be using copper plugs in our cylinder heads. The copper and aluminum can metal bond over time causing a lot more issues than a cel light. The best rule of repair is ALWAYS first check what you just replaced.

Yeh. I know i shoudlve double checked the new plugs. But i was just assuming that the people working in an auto parts warehouse would have an IQ with double digits. Im still confused as to how they decided to give me plugs that werent even made for my car?!? Oh well. Ive got the NGK Iridiums and im installing them as we speak. Ill write back to let you guys know if everything worked out ok.

[6G72Galant]

Update: So after replacing the Vpower plugs with NGK iridiums, I didnt bother to reset the CEL. It remained on for about 50 miles, and I decided to reset it this afternoon. However, when I went to check the codes, I had 3 codes....

-Random/Multiple cylinder misfire
-Random/Multiple cylinder misfire [Pending]
-P0174 System too lean Bank 2 [Pending]

Im confused as to what the System too lean is? And why is it only pending? I was told by a mechanic that usually system too lean codes are related to o2 sensors. Where as system too rich codes, on both banks, are related to the MAF sensor. Any ideas?

[2kblkgalant]

maybe due to the crack you have in your intake sucking more air causing lean

[01blackG]

Clear the codes then drive the car for a bit. See if they come back. If they dont come back, then the lean code could have been created by the misfire codes. Sometimes you get more then one code for the same problem.

[WarmAndSCSI]

You don't want to be using copper plugs in our cylinder heads. The copper and aluminum can metal bond over time causing a lot more issues than a cel light. The best rule of repair is ALWAYS first check what you just replaced.

The plugs themselves aren't copper... the fucking electrodes are. The rest of the spark plugs are steel and ceramic. Plenty of aluminum head engines use copper plugs.

Why you don't want to use copper plugs is because of their relatively short change interval and the pain in the ass that the rear bank is to access. Other than that, copper plugs are great. The only metallurgical concern you should have is if you have cast iron cylinder heads and you fail to use anti-seize on the threads... but this of course does not apply to any modern Mitsubishi engine.

[6G72Galant]

Update:

I checked the CEL codes, and the P0174 "System too lean Bank 2" is gone. However, I had a code for P0300 "Random/Multiple cylinder misfire" and "Random/Multiple cylinder misfire [pending]".

Now, there were some very heavy rains on thursday evening. While driving with my CAI installed, Im assuming some water got into the engine because the idle was a bit rough. So I promptly stopped the car and let it sit for about 30 minutes. I switched out the CAI for my SRI and everything was fine. Is there a chance that the P0300 code was from the rain? Because I cant see that code coming from the spark plugs.

[GSpeed]

Are either of the following diagrams correct firing order / plug wire location for 2002 Galant 3.0 V6;
http://autorepair.about.com/library/firing_orders/bl-fo-1800.htm
http://www.fixya.com/cars/t2907906-firing_order_1999_mitsubishi_diamonte
Would 1-3-5 in the back from left to right and 2-4-6 in the front from left to right, while facing front of vehicle, be correct cylinder locations?

[ezekiel.glnt]

Update:

I checked the CEL codes, and the P0174 "System too lean Bank 2" is gone. However, I had a code for P0300 "Random/Multiple cylinder misfire" and "Random/Multiple cylinder misfire [pending]".

Now, there were some very heavy rains on thursday evening. While driving with my CAI installed, Im assuming some water got into the engine because the idle was a bit rough. So I promptly stopped the car and let it sit for about 30 minutes. I switched out the CAI for my SRI and everything was fine. Is there a chance that the P0300 code was from the rain? Because I cant see that code coming from the spark plugs.
fix the crack,im thinking the code is related to the crack u got.