not always firing on #1

[john h]

could check ohm resistance on your #1 plug wire, to see if you have an opencc

I m a nit of an idiot when it comes to electrical issues.  I do have a meter though.  Can you run through the procedures to test the new and old wire for comparison?

[john h]

Im a bit lost when it comes to electrical issues.  I have a meter.  Could you go through the procedure to test the new and old wire?

[72cudamaan]

Im a bit lost when it comes to electrical issues.  I have a meter.  Could you go through the procedure to test the new and old wire?

 I doubt you have 2 bad plug wires for the same cylinder but just turn your meter to the ohms setting.
 Touch each end of the wire to each lead of the meter. You should see a number if the wire has some resistance.
If the wire is broken then your meter will show zero resistance (an open).

[Bullitt-]

  and it would be a good idea to get a reading on another plug wire of similar length out of the same set to see if there is higher resistance in the suspect wire..... I've gotten extremely different resistances from one set to another.  Also wiggle the suspect wire while connected to the meter.
   Old trick used to be to run the engine in pitch dark....if you have bad plug wires you will see a little fireworks show from all the arching.

[cudabob496]

When check wire, resistance, obviously take plug wire off and over to the work bench for the test.
Most high performance wires could be around 50 ohm per foot.
Can also take number one wire off the plug, but leave it connected to distributor,
put in a spare plug on the wire, and
see if the plug is firing when you touch it near a ground point on the engine.

I assume you have a new distributor cap installed?

[john h]

I do have a new cap and rotor installed. I will try to pull the wire and do the resistance check tonight after baseball.  it gets pretty busy around our house during the week with a ton of kids activities.  I'm sure I can fit that in though. Thanks for all the help guys. I just wish I could get to trying out all the suggestions sooner.

Thanks.
John

[john h]

http://www.cuda-challenger.com/cc/index.php?topic=92838.0

Is this a possible cause for the not firing issue or would that cause all the cylinders to have issues or weak spark? (distributor pickup coil)

John

[72cudamaan]

http://www.cuda-challenger.com/cc/index.php?topic=92838.0

Is this a possible cause for the not firing issue or would that cause all the cylinders to have issues or weak spark? (distributor pickup coil)

John

The pickup coil would effect all cylinders.

[cudabob496]

gotta be a bum wire, or boot connectors

[Strawdawg]

If your timing light blinks consistently and the mark stays steady, I would say it was firing.

What is the compression on that cylinder?

[cudabob496]

If your timing light blinks consistently and the mark stays steady, I would say it was firing.

What is the compression on that cylinder?

a blinking timing light might not mean the plug is firing, if there are other grounds.
I'd take plug out and check for spark while holding plug on block.  Just don't touchee!!

[Strawdawg]

a blinking timing light might not mean the plug is firing, if there are other grounds.
I'd take plug out and check for spark while holding plug on block.  Just don't touchee!!

First page, Bob.  He stated he had changed the wire and the plug.

First post stated the timing light seemed slow on that wire compared to others....which leaves the distributor cap as a possible culprit is the post is bad, or maybe a hairline crack...but, I would check the compression because if it is substantially low, the cylinder will not fire completely and leave the plug a bit wet which can bleed the voltage across the insulator to the case making for an erratic spark

Given his comments that he saw little difference in pulling any wire, it may be the ignition box as well.  I am sure that Neil has asked about the air gap in the distributor, but it is worth verifying that it is correct on all the lobes as well.

I believe in proving things are okay so they can be eliminated from the equation-hence my question regarding the compression

[cudabob496]

First page, Bob.  He stated he had changed the wire and the plug.

First post stated the timing light seemed slow on that wire compared to others....which leaves the distributor cap as a possible culprit is the post is bad, or maybe a hairline crack...but, I would check the compression because if it is substantially low, the cylinder will not fire completely and leave the plug a bit wet which can bleed the voltage across the insulator to the case making for an erratic spark

Given his comments that he saw little difference in pulling any wire, it may be the ignition box as well.  I am sure that Neil has asked about the air gap in the distributor, but it is worth verifying that it is correct on all the lobes as well.

I believe in proving things are okay so they can be eliminated from the equation-hence my question regarding the compression

sounds reasonable!

[john h]

If your timing light blinks consistently and the mark stays steady, I would say it was firing.

What is the compression on that cylinder?

Compression on that cylinder is 140.  it's 140 on the one next to it as well.  the other 2 on that bank I have not checked yet because I need to remove the headers to get to them.  jsut had a small amount of time to mess with it.  I am taking the day off tomorrow so hopefully I can work on it until I get it worked out.  I wonder if I should pick up a new ECU and dist rebuild kit?  just to make sure.  I ohm checked the wire and I'm not sure what scae I should have been using, but I got nearly 9 on the meter.  the other (2) plug wires I checked were the same. I checked an old wire laying around and it was around 6.7  the difference was a 7mm vs an 8mm wire.  similar length.  The reason I checked the plug in the first place was the timing light was not steady and sometimes did not strobe at all. 
John

John

[cudabob496]

Compression on that cylinder is 140.  it's 140 on the one next to it as well.  the other 2 on that bank I have not checked yet because I need to remove the headers to get to them.  jsut had a small amount of time to mess with it.  I am taking the day off tomorrow so hopefully I can work on it until I get it worked out.  I wonder if I should pick up a new ECU and dist rebuild kit?  just to make sure.  I ohm checked the wire and I'm not sure what scae I should have been using, but I got nearly 9 on the meter.  the other (2) plug wires I checked were the same. I checked an old wire laying around and it was around 6.7  the difference was a 7mm vs an 8mm wire.  similar length.  The reason I checked the plug in the first place was the timing light was not steady and sometimes did not strobe at all. 
John

John

9 is okay, if the other wires are the same. On your distributor cap, does the contact for the #1 wire look any different than
the other contacts?

Also, does your #1 wire run without coming into a lot of close proximity to other wires? If its at least 1/2 inch away from other
wires, you should be ok.

Try setting your idle up around 1200 to 1400, and see if problem goes away. Some alternators are crappy at putting out the juice at low
rpms.  Also, replaced your voltage regulator recently? You said you lights dim way down at stop lights.