Coil Pack and Spark Plug wire resistance ?

[ikle]

I did a search and it was said that a good coil pack resistance is between 11.5-13.0 ohm's. So I tested mine and this is what I came up with:
1-4 = 10.16 ohm's
2-5 =10.17 ohm's
3-6 = 10.47 ohm's
I did this cold with the battery disconnected.

I also tested two sets of spark plug wires the first was Magnacore: 1 = 4.52 ohm, 2 = 3.37 ohm, 3 = 3.36 ohm, 4 = 3.32 ohm, 5 = 3.70 ohm and 6 = 4.05 ohm

The secound set is Kirbans high performance wires: 1 = 0.66 ohm, 2 = 0.50 ohm, 3 = 0.47 ohm, 4 = 0.47 ohm, 5 = 0.50 ohm and 6 = 0.59 ohm.

How does the coil look ( do i need a new one since its not in the 11.5-13.0 ohm specs ) and which spark plugs should I use. Thanks for your replies, Kyle.

 

[Lil Truck]

Coil Pack testing is done at operating temp. Take it for a 20 min drive or more then check.

 

[earlbrown]

I've never seen a coil in the 10K range but that looks fine. They aren't shorted and they aren't open.

What kind of running condition are you trying to diagnose?

 

[ikle]

I've never seen a coil in the 10K range but that looks fine. They aren't shorted and they aren't open.

What kind of running condition are you trying to diagnose?

Rough idle and when I pulled the plugs #1 plug looked to be "Carbon Fauled" so I figured I would look at the coil/module and wires first. What do you think ? Also which spark plug wire, from above, is better ? The resistance of Kirbans wires are much lower when compared to the Magnacore wires so is that a bad thing or a good thing ? Thanks for your help, Kyle.

 

[TurboDave]

I did a search and it was said that a good coil pack resistance is between 11.5-13.0 ohm's. So I tested mine and this is what I came up with:
1-4 = 10.16 ohm's
2-5 =10.17 ohm's
3-6 = 10.47 ohm's
I did this cold with the battery disconnected.

I also tested two sets of spark plug wires the first was Magnacore: 1 = 4.52 ohm, 2 = 3.37 ohm, 3 = 3.36 ohm, 4 = 3.32 ohm, 5 = 3.70 ohm and 6 = 4.05 ohm

The secound set is Kirbans high performance wires: 1 = 0.66 ohm, 2 = 0.50 ohm, 3 = 0.47 ohm, 4 = 0.47 ohm, 5 = 0.50 ohm and 6 = 0.59 ohm.

How does the coil look ( do i need a new one since its not in the 11.5-13.0 ohm specs ) and which spark plugs should I use. Thanks for your replies, Kyle.

Just to correct symatics, I'm sure all your readings including the wires are actaully Kohms and not ohms. If they're all kohms they make sense.
Taking resistance readings on modern day plug wires is somewhat meaningless unless you're looking for an open wire.
Modern plug wires have no metal core or winding, it's all non metalic and consist of very tight windings to suppress RFI and EMI. The actaully conductor inside the wire is usually a carbon based fiberglass conductor that wound around a carbon core, and is hundreds of times longer that the physical length of the plug wire.

The only proper method (not available to us on the street) to measure wire performance is to measure its impedance, NOT resistance.

In short, trying to compare one modern set of wires to another using only your resistance measurements will tell you nothing of a particular set's performance, unless the readings are rediculously skewed high.

 

[TexasT]

So I believe your next step becomes compression and leakdown tests .
What kind of driving had these plugs seen?
Lots of sitting in traffic?
Stop n go around town?
Is your fuel pressure set high at the regulator?
Have your injectors been cleaned lately?
You might swap the one hole injector with another and see if your carbon foul moves with it.

Posted from the TurboBuick.Com mobile app

 

[Lil Truck]

If the plugs have some months use you may just want to get a new set and then check for any problems. I change mine a few times a year depending on conditions Street/Strip , leaded fuels ......

 

[ikle]

Ok here is some info:
Cold startup engine runs smoother and Vac gauge fluctuates slowly .5in of mercury. WB02 12.6-13.6.

Warm at normal operating temps engine runs rougher, Vac gauge fluctuates 1-2in of mercury but seems be fluctuate with rpm. WB02 14.6 @ idle and cruise.

ScanMaster #'s warm @ idle
AF 5
L8 33-38
Bat 13.6-13.9
Int 119-137
BLM's 125 also 125 @ cruise at 2,000 rpm
Clt 162
Ats 83
Rpm 725-850
TPS .44
Iac 19
Cc climbs up 1-4 counts steadily

Ohm coil pack warm set on 20k:
1-4 = 11.76
2-5 = 11.46
3-6 = 11.53

Checked spark plug gaps Autolite 23 are a tight 34 using wire type gauge, but when I check with disc type gauge its a tight 28, which would be accurate ? Thanks for all the help, Kyle.

 

[ikle]

Ok here is some info:
Cold startup engine runs smoother and Vac gauge fluctuates slowly .5in of mercury. WB02 12.6-13.6.

Warm at normal operating temps engine runs rougher, Vac gauge fluctuates 1-2in of mercury but seems be fluctuate with rpm. WB02 14.6 @ idle and cruise.

ScanMaster #'s warm @ idle
AF 5
L8 33-38
Bat 13.6-13.9
Int 119-137
BLM's 125 also 125 @ cruise at 2,000 rpm
Clt 162
Ats 83
Rpm 725-850
TPS .44
Iac 19
Cc climbs up 1-4 counts steadily

Ohm coil pack warm set on 20k:
1-4 = 11.76
2-5 = 11.46
3-6 = 11.53

Checked spark plug gaps Autolite 23 are a tight 34 using wire type gauge, but when I check with disc type gauge its a tight 28, which would be accurate ? Thanks for all the help, Kyle.

I also did a compression test, engine warm, throttle body opened at WOT, orange wire unplugged and ignition module unplugged:
1 = 172 2 = 170
3 = 172 4 = 174
5 = 174. 6 = 170
Thanks again, Kyle.

 

[ikle]

I also did a compression test, engine warm, throttle body opened at WOT, orange wire unplugged and ignition module unplugged:
1 = 172 2 = 170
3 = 172 4 = 174
5 = 174. 6 = 170
Thanks again, Kyle.

Also all spark plugs were remove.

 

[Lil Truck]

From what I can determine you have a big vacuum leak. 13-16 in is normal on my car with a 212/212 cam, stock cam may be higher.

 

[Lil Truck]

Have you checked the PCV ?

 

[ikle]

So I believe your next step becomes compression and leakdown tests .
What kind of driving had these plugs seen?
Lots of sitting in traffic?
Stop n go around town?
Is your fuel pressure set high at the regulator?
Have your injectors been cleaned lately?
You might swap the one hole injector with another and see if your carbon foul moves with it.

Posted from the TurboBuick.Com mobile app

Compression test done look at above post.
I drive the car once in a while on nice weekends days for a 1 hour cruise with some WOT blast.
Fuel pressure set at 42-43 lbs with Vac off
My 42 lbs injectors are 3 years old and when I store it for the winter I fill up the tank with fresh 93 oct and a full can of Sea Foam and I change the fuel filter every spring.
I would move the #1 injector to a different location and install new plugs if it is necessary. Thanks for your reply, Kyle.

 

[ikle]

From what I can determine you have a big vacuum leak. 13-16 in is normal on my car with a 212/212 cam, stock cam may be higher.

I am a little confused, my vacuum gauge reads around 18in ?

 

[ikle]

Ok I see where the confusion lies, I ment to say the vacuum fluctuates between 17.5-18.0in when cold and it fluctuates between 18-16in when at normal operating temps. Sorry for the confusion, Kyle.

 

[ikle]

Have you checked the PCV ?

I haven't but a couple of years ago I did install a Kynar check valve inline with my pcv.

 

[Lil Truck]

That is much better! The everything looks ok to me. The only time I had a similar problem was at the track when I sucked the MAF screen into the sensor. It was a stock MAF, car stumbled and ran rough. I see you have a LS1 MAF is it new?

 

[ikle]

Also spark plugs have less than 500 miles on them.

The three things that bother me about his car is:
1) rougher than normal idle
2) #1 spark plug showing signs of carbon when the others are clean
3) having an annoying ticking sound that starts at around 2,000-2,200 rpm's

When I do a WOT third gear pull it runs clean but it doesn't rev past 5,000-5,200 rpm's

 

[ikle]

That is much better! The everything looks ok to me. The only time I had a similar problem was at the track when I sucked the MAF screen into the sensor. It was a stock MAF, car stumbled and ran rough. I see you have a LS1 MAF is it new?

It's about 6-7 years old

 

[Lil Truck]

I have run plug gap all the way from .035-.020, tighter for higher boost levels. If you have a set of calipers you can check your gauges. Did all the plugs look the same?

I would clean or replace the PCV just to see.