Coil Pack Cel Codes

[jclemen]

The kid is away at college and calls me today saying the car is surging and idling rough while at a stop. I gave instructions to rent a code reader, the following codes are present: p0302, p0304, p0306 which are cyclinder misfires on cylinders 2,4, and 6 respectively. (I'll also add p0135 is there too, I was aware of this this past summer and havent gotten around to cleaning the ICV.)

I'm reading that the misfire codes potentially mean coil packs. I've done some searching on this site and have found a few threads, one where the coil packs weren't at fault but the wires of the packs themselves.

My question is; Is there one harness for the three packs on the even side of the motor or three individual wires to each pack? I'd look but the car is not in the driveway. I'm surprised the whole side is out and am thinking that if there's just one wire for all three then that's where I'd start.

Any feedback/direction is appreciated

I should add this is for a 94 ES300 with approx 130k miles.

Thanks

[jclemen]

http://images.google.com/imgres?imgurl=htt...sa%3DN%26um%3D1

Hmmmm. OCV perhaps?

[George_Jetson]

http://images.google.com/imgres?imgurl=htt...sa%3DN%26um%3D1

Hmmmm. OCV perhaps?

No, variable valve timming is for later engines. You state that it runs rough at idle, how does it drive otherwise? The first thing I would suggest it to check vac hoses. CLOSELY, hoses over time will dry and crack, especially at the ends. Don't forget to check the PCV valve hose, it is a little hard to see unless you are intentionally looking for it, very easy to overlook. How long since the last tuneup?

[jclemen]

Thank GJ - Tune-up is fair, it's time.

Will the tune-up/vacuum issues throw the CELs for all three cylinders? I plan on making the trip this Saturday and bringing whatever parts are necessary

to get it back to pre-CEL condition so I can get it home (60 miles) to the warm garage. The kid has a non-heated individual garage stall but when its 5 degrees, its not the most fun environment to work on a car.

[George_Jetson]

A leak could cause lean mis-fires, which is why I was asking about how it ran above idle. The coil packs are all tied to the same 12 volt source, the ignitor grnds the individual coils. Of course you can extrapolate that there is at least one splice for the wire that supplies power to the coils, and you can check it (should have 12v all the time the engine is on). If the engine runs reasonable above idle, then I would strongly supect leaks. Bring some assorted sizes of vac lines and some tape (in case the flex tube is leaking).

As far as tune-ups, I always recomend doing one if there is a driveability issue, and if it has been awhile. I used to work at a dealership, you would not believe how many cars came in with complaints, cel, yet had not had a tuneup in a long time. Part of this I attribute to the auto manufactures themselves, I believe that the advertisments that their cars can go 100k without a tuneup is BS. Missfires can damage cats due to unburned fuel burning inside the cat. There are also other issues, but suffice to say, if they really thought they could make it to 100k, why doesn't the warrenty extend that far?

[jclemen]

The car runs fine above idle so I'll start with the vacuum lines. I'll bring a tester too to ensure the harness is good. I appreciate the direction, no need to throw money at it just yet. I'll let you know how it goes.

Best Regards

[jclemen]

The car runs fine above idle so I'll start with the vacuum lines. I'll bring a tester too to ensure the harness is good. I appreciate the direction, no need to throw money at it just yet. I'll let you know how it goes.

Best Regards

I replaced only the front three spark plugs and sprayed some carb cleaner into the TB and down the hole into the IACV. The car seemed to run better but it still has the same symptoms. I'm still getting misfire on 2 and 4 but the code for 6 hasn't returned since reset. I'm ordering the intake gasket and a new pcv valve and will do the remaining three plugs when the car comes home for holiday break this week. I'll have a chance to tear it down and perform a more robust diagnosis.