when to replace the spark plug cord?

[leblancc99]

I am troubleshooting a big ignition problem on my almost new impreza (2 month out of warranty.

 

So far, I have to change the spark plugs, the electrode opened and the gap is now over 60mill!

 

The coil is to be replaced, the primary resistance (ECU side) is in the mega-ohm range and it should be 0.73ohm so the primary is burned. The secondary resistance (plug side) is 12.8kilo-ohm almost perfect

 

The wires look good, very good but they have about half the resistance when measured with a multimeter (in ohm):

#1 has 6.3 should be 10.6

#2 has 7.7 should be 13.7

#3 has 6.2 should be 11.1

#4 had 8.0 should be 13.7

 

Should I order a new set? seems that the resistance is negligeable compared to the arc produced by the plug (the air being a much bigger resistance)

 

Now the big question:

 

I have checked the resistance of my injectors: it is supposed to be 11-12ohm, I am getting 13, 13.2, 13, 12.9 are they toasted? this is the 1400$ question for me because that is what the dealer wants for this!

 

I am not really equipped to do the injector work myself, my car sits outside and I do not have that much free time

 

Please advice

 

original thread:

http://www.ultimatesubaru.org/forum/showthread.php?t=19346

[SevenSisters]

If it ain't broke, don't fix it.

 

After 13 years I still have the original wires. If you don't have a misfire code, I doubt if there is anything wrong at your car's low mileage and age.

As far as the fuel injectors go, I'd say the same thing. As I recall, all I needed to change one of mine that threw a code was a phillips screw driver. $100 and 15 minutes later I was done. Do the math for 4 of 'em.

 

Do you know if your VOM is reading correctly and set at a senstive range?

[leblancc99]

Unfortunatly, I am getting misfire code on all four cylinders, P301, P302, P303, P304. I explained in details on the other thread. The car almost doesn't run under 2000 rpm, after, it picks up, I have unburned fuel smell out of the exhaust, the engine vibrates alot at idle and when I can finally get the car moving, it produces blue smowe. CEL flashes then steady ON

 

I have decided to change the ingnition coil after testing the resistance of the primairy wires.

 

I will also change the spark plugs, the old one opened up, I put NGK Irridium IX and less tha one year after that, I have these problems, maybe the plugs have nothing to do with it but I am going back to regular platinum plugs.

 

I wasthinking about changing the spark plug wires as well but since they are still below their resistance, I will simply apply silicon on them.

 

As far as the injectors, they are pricey in my region, I could order then from a mail order if I can find one that will ship to Canada. There is some work to be done to replace them, I had to strip some thing out of the engine bay only to disconnect the wires of the injectors, I suspect that there is much work because the fuel rail has to be removed as well.

 

The good thing is that I found a service manual on the net

 

My VOM seems perfact, it is a numeric one , not the best quality but seems fairly precise. I have another one, analogic but is it only precise with current and voltage

 

I am hoping that the new ingnition coil and the new plugs with the proper gap will solve the problem.

 

 

 

If it ain't broke, don't fix it.

 

After 13 years I still have the original wires. If you don't have a misfire code, I doubt if there is anything wrong at your car's low mileage and age.

As far as the fuel injectors go, I'd say the same thing. As I recall, all I needed to change one of mine that threw a code was a phillips screw driver. $100 and 15 minutes later I was done. Do the math for 4 of 'em.

 

Do you know if your VOM is reading correctly and set at a senstive range?

[avk]

On a '00, the coil assembly also includes the ignitor. If you are certain the coil is bad and set on replacing it, you'll have both new windings and a new ignitor. Hopefully that will fix the problem. But are you out of the powertrain warranty?

Funny, those dealers. FSM has a lenghty description of misfire diagnosis, flowcharts and all. They don't think it was written for them.

[leblancc99]

First of all, I have 130000km on my car , way more than the 100000km warranty limit for the major component warranty. Second of all, the ignition is covered by the emission control warranty and the normal bumber to bumper warranty of 36 month 60000km

 

One might argue that is could fall under warranty if the coil were on the 5years/100000km warranty but since I am more than double the mileage and over one year past the std warranty, I am stuck with it.

 

I do not mind that much but now I feel that my local dealer is a crook, you can see the other thread for more info.

 

 

 

On a '00, the coil assembly also includes the ignitor. If you are certain the coil is bad and set on replacing it, you'll have both new windings and a new ignitor. Hopefully that will fix the problem. But are you out of the powertrain warranty?

Funny, those dealers. FSM has a lenghty description of misfire diagnosis, flowcharts and all. They don't think it was written for them.

[allairewannabe]

I just had my coil replaced -- and the new one is defective. If there is any snow or rain, the motor misfires and the CEL flashes. If I touch the coil while the motor is running, I get a pretty good shock off it. The dealer admitted the new one was a dud and said he'd replace it. (Of course, it was the only one they had in stock. So now I'm waiting for one to come in on back-order.)

[Setright]

The plug wire resistance is off, but consider that they operate at far higher voltage than your VOM tests them at.

Anyway, the real trouble with plug wires is when they break internally and cause misfires. This is often difficult to test for because the resistance measured using a low voltage VOM is usually okay.

 

One broken plug wire will often lead to a periodically lumpy idle, most often after the engine has been asked to do some hard work. It is possible that more than one of your plug wires is broken. If so, this would be consistent with your problem.

 

I doubt it's the injectors, you wouldn't get a fuel smell if they were staying shut.

[richierich]

Plug wires are pretty common problem on the Phase 2 engine. Subaru has dropped the price on the wires to retail of $35.00, compare that to the other wires that go for $42-59.00, and you know there might be a problem. Unfortuately, that is not your problem. You have to start with a coil pack. I can not see al the injectors going bad all at once.