Need some advice on check engine light.

[poky]

Hi, I'm new here, recently just bought a 2001 Galant ES with 88000 miles on it.

Every morning, when it cold starts, the car vibrate like crazy, even worst when you put it in gears.
You can feel the dash board is shaking bad.
But after you drive for a few second, it starts getting normal, but the CEL's on.
and it is only happened when cold starts, after that, it will runs fine for the entire day, but next day morning it's same again.

This happened to me these few days, and after I change the radiator (the old one has cracks)
And before change the radiator, I had the CEL for O2 sensor, and it has been replaced, and has been running good since last few days.

I've tried clean the MAF and TB, also put some seafoams in the gas tank also the engine oil.
I noticed the light went off after seafoam was in after driving 10 miles.

I went to the Autozone to get the code scanned, it was P0304 when it's first doing that. And second time when it came back it was a different one P0303

The spark plug has not been changed, do you think it might be the problem or any other advices are welcome!

Thanks!

[RAZ_76]

P0303- Cylinder # 3 misfire
P0304- Cylinder #4 misfire

This is my advice, replace all 4 spark plugs with factory ones, no aftermarket crap. Also replace the 2 spark plug wires. If that doesn't fix it, then replace the 2 coil packs and you are good to go.

[poky]

Thanks for the quick reply!
I searched the spark plug here, and someone recommended NGK's, but it has to be pre-capped.
But the factory one has already done that, so I don't need to buy a cap tool myself.
I think I might try that.

Thanks again for the advice!

[RAZ_76]

The gaping tool you can get from like Autozone dude for under 1 dollar, it's round like a silver dollar. Make sure and check them anyway to make sure they are gaped correctly.

[Gtsnapper]

^x2, if you had to go back to the dealer about any problems, they'd ask if you'd checked them.

It's easy and just takes a couple of minutes.

[ni2]

That would be good advice. One thing though. My gallant came from the factory with platinum tipped plugs. These last a very long time. I went to change mine at 85K and was very surprised that the plus were in very good shape. Actually left them in for another 50K and are now going to change them. These can also be expensive. The lowest price I was able to get was from sparkplugs.com. They sell the original NGK plugs used for the car. The dealer wanted $15 each. Since you don't know what is actually causing the problem, if the plugs look good I would suggest getting none platinum after market spark plugs just for experimentation. I think you can buy a set of 4 for about $5 bucks. If that solves the problem you can buy the correct plugs and drive away with a smile on your face. Oh, I almost forgot. You may want to look at your spark plug wires in total darkness. I know what you are thinking but once I was diagnosing a random misfire on a Nissan with a napZ engine. These have twin plug heads. One of the old timers came up to me and said "turn off the lights" and there it was. A tiny little spark coming of the wire. A new set of wires later the car ran smooth.

[RAZ_76]

Chenge the plugs and wires anyway, it's routine maintenace. Then go from there, if that doesn't fix the problem then you atleast have fresh plugs and wires and know that one of the coilpacks is bad. If it turns out that ut is one of the coilpacks, replace both.

Spark plugs you need are NGK PFR6G-11
GAP 0.039-0.043 inch

[RastaAlejandro]

Spark plugs you need are NGK PFR6G-11
GAP 0.039-0.043 inch

is that gap the same for the 6cyl?

[poky]

Just came back from O'Reily
I bought the NGK Laser Platinum spark plugs for $9.89 a piece, also got the gaping tool.
This will be my first time changing the spark plugs by myself.
I will keep update on how it goes after change.

Thank you guys!

[RAZ_76]

is that gap the same for the 6cyl?

Yes it is.

[poky]

I have installed the plugs and wires.
I also fill in the transmission fluid just to replace the missed fluid from the radiator replacement, only filled with half qt.
It was running fine for couple days.
Now the SES light came on again, went to Autozone, it says mis-firing on cylinder 3.
The car now is feel funny when put the gear in D, it feels like going to stall, and when giving gas in the 1st gear, the acceleration is sluggish, but other gears runs just fine after the 1st gear.
I've tried idle in N, and it idles just fine, would it be the transmission when I filled with the extra fluid?

Please help, thanks!

[poky]

I did some search on here.
Seems like the coil pack is bad, but since the SES only shows misfiring on cylinder 3, will it be cheaper just replace the coil boot?
Another question, if I ever get a coil pack, does it comes with coil boot?

Thanks!

[poky]

Guys, please help me out here!
I thought it was the coilpacks failure, so I go ahead and change it out, but does not help.
And I thought it was the newly installed Bosch plug wire(search says Bosch is bad in our cars)
So, I install the stock one back, and still nothing change.

One thing I tried today is unplug my MAF wire, it idles high at 1000rpm, and vibrate a little, but no sluggish feeling when accelerate from a stop.
Then I took the MAF off, use the MAF cleaner to clean again, re-installed back in, and wire plugged, the sluggish feeling came back again when take off from stop, the idle is at 800pm.

Could it be the bad MAF?

[RedGalant2k1]

Yes, it could be.

[poky]

Here I'm back again!
I've installed a new MAF, but the problem is still exist.
The car vibrate bad, but whenever I unplug the MAF connector it runs fine again.

Seems like a sensor in the intake system somewhere is bad.
This is my another guess.
Would it be a TPS?

The SES does not give me any error codes other than the random misfiring code.

Please help!

[RedGalant2k1]

Have you checked for vacuum leaks?

[poky]

Yes, I've check almost everywhere from the intake tube to manifold, can't find any leaks or cracks.
I'm going to the dealer tomorrow see what they can do for it, thanks for advice!

[guynlidia2006]

I think you would of saved alot of money if you just took it to a shop and let the professionals test and let you know what is wrong, yeah you would have to pay a diag fee but when your guessing it can become very expensive... You dont have to let them repair it but at least you know what the problem is... I mean how much have you speant and still the problem is there...

[poky]

^^^
That's so true!
Sometimes I just keep telling myself it might be just a small easy fix-up problem, and just keep doing and changing stuff out, and still don't get the problem fixed.
And yet, since you spent all these time and money, you don't want to give up.

I took it to the Mitsubishi dealer yesterday, they charged me $85 for dia. fee,
and half hour later, the mechanist told me the valve gasket was leaking, and causes the plugs, wires and coilpacks shorted out, he quote me everything for $495.
When I change the spark plug, I didn't aware of the oil leaking that leaks into the valve cover.
The manager told the guy who worked on my car has been work on Mitsubishi for 16 years, so this should fix the problem I had.

At same time, I also asked them to change the timing belt, car had 91000 miles already, might as well doing that while the car is there, that's for another 500ish dollars....ouch

Also, the manager recommended me to do the 60000 miles service, since I don't know the ex-owner's history, and I want to have a reliable car for school. This services included full car inspection, all fluids flush, I did ask if it's safe to do a tranny flush, I checked it last time myself, it was burnt and brown looking, I read on here said if your car has a high mileage it's not a good idea. But the manager said 91k is nothing compare to 150k.

And all this costs $1500...:smt091

I hope this does worth it to let me get through another 3 years of school.

Cheers!