Wire Arc?

[mawint]

I recently changed plugs and wires in my truck and it ran great for the first few weeks. It then started to run rough at idle and hesitate on take off once the truck heats up.

 

Tonight upon checking things out, I found two of the plugs had loosened up (like a quarter turn). Tightened them back up and went for a drive, I would say it is probably 90% there but still idling a little rough and hesitating on takeoff. Not nearly as bad as it was though.

 

Rolled down the window to hear things and I can hear what seems to be arcing noises on the drivers side. I parked in a dark spot and looked for little blue arcs but didn't see any. Anyone had these kind of issues with new plugs and wires?

[txab]

2004 Avalanche? 5.3? Plug #, plug gap please.

 

Can't say I've ever had a properly torqued plug "loosen up" before. Wires touching the manifold anywhere?

[mawint]

Yup 5.3, gapped to .060. I will have to check on the plug number but they are champions.

 

I pulled all the plug wires off today and checked them, I didn't pull the plugs out however to check those since they are new. Putting them back on though I noticed one was a little hard to "click" on, one seemed a little soft to click on and the other two seemed normal on that side. At the time I just thought of this as varying degrees of grease on the plugs.

 

The plugs that loosened up were on the same side that I had a rich running condition from an O2 sensor. The old ones on that side were all carboned up.

[txab]

The plug is supposed to gapped to ..040 not .060. GM changed the recommended plug and gap to get better running performance. You would be better of using AC Delco Iridium

41-985 is now 41-110

 

 

Service Information 2000 Chevrolet Chevy K Silverado - 4WD | Sierra,
Silverado, Suburban, Tahoe, Yukon (VIN C/K) Service Manual | Document
ID: 1903277
--------------------------------------------------------------------------------

#03-06-04-060A: Information on New Spark Plugs and Gapping - (Feb 12, 2007)


Subject: Information on New Spark Plugs and Gapping


Models: 2004 Buick Rainier

2002-2004 Cadillac Escalade, Escalade EXT

2003-2004 Cadillac Escalade ESV

2004 Cadillac CTS-V

1997-2004 Chevrolet Corvette

1998-2002 Chevrolet Camaro

1999-2004 Chevrolet Silverado

2000-2004 Chevrolet Suburban, Tahoe

2002-2004 Chevrolet Avalanche

2003-2004 Chevrolet Express, TrailBlazer

1999-2004 GMC Sierra

2000-2004 GMC Yukon, Yukon XL

2001-2004 GMC Yukon Denali, Yukon XL Denali

2002-2004 GMC Sierra Denali

2003-2004 GMC Envoy XL

1998-2002 Pontiac Firebird

2004 Pontiac GTO

2003-2004 HUMMER H2

with 4.8L, 5.3L, 5.7L or 6.0L V-8 Engine (VINs V, P, T, Z, G, S, N, U -- RPOs LR4, LM4, LM7, L59, LS1, LS6, LQ9, LQ4)

 

Attention: Please disregard the Set Gap Per Vehicle Specification
statement on the side of an ACDelco® Iridium Spark Plug Box. The
statement will be removed from the boxes in the future.



--------------------------------------------------------------------------------

This
bulletin is being revised to bring attention to the Set Gap Per Vehicle
Specification on the ACDelco® Iridium Spark Plug Boxes. Please discard
Corporate Bulletin Number 03-06-04-060 (Section 06 -- Engine/Propulsion
System).


--------------------------------------------------------------------------------

•
A new spark plug has been released for use in the above vehicles. The
new spark plug has an Iridium tip instead of the current Platinum tip.
Due to the different tip design, the gap of the spark plug has also
changed.

• The new spark plug, P/N 12571164 with AC Delco P/N 41-985, is gapped to 1.01 mm (0.040 in) when the spark plug is made.


Notice:
The spark plug gap is set during manufacturing and should not be
changed or damage to the spark plug may result. Any new spark plug found
to not be properly gapped should not be used.

GM
bulletins are intended for use by professional technicians, NOT a
"do-it-yourselfer". They are written to inform these technicians of
conditions that may occur on some vehicles, or to provide information
that could assist in the proper service of a vehicle. Properly trained
technicians have the equipment, tools, safety instructions, and know-how
to do a job properly and safely. If a condition is described, DO NOT
assume that the bulletin applies to your vehicle, or that your vehicle
will have that condition. See your GM dealer for information on whether
your vehicle may benefit from the information.

WE SUPPORT VOLUNTARY TECHNICIAN CERTIFICATION


© 2008 General Motors Corporation. All rights reserved.

[mawint]

Really? Was not aware of that, when I looked it up everything I saw listed was .060 but maybe I didn't search for a specific year.

 

Is there anything wrong with the champion plugs in particular? Curious minds.

[txab]

Most people report AC Delco running better in these engines. If you want to stay with Champion, that's fine, but you need new plugs, you can't re gap what you have now.

Checking a couple of places ACD are cheaper than Champions

[mawint]

I will pick up some new ones tomorrow and put them in.

 

Thanks, never had this much difficulty with plugs and wires before. Getting ridiculous.

[mawint]

Switched out the plugs today with new pre-gapped AC Delcos. Purrs like a kitten now. When taking out the champion plugs the front two on the drivers side were almost white, more so than normal. Ticking went away too.

[txab]

[gmtech4]

champions suck in GM engines since .....1849 !!!

[mawint]

champions suck in GM engines since .....1849 !!!

Ha! Well if nothing else weird happens, I got another 100,000 before I need to change them again.

[Daryl LBZ]

Anything electrical be it plugs, wires or sensors I always buy AcDelco.

 

Sent from my Samsung Galaxy S3

 

 

[00Silverado4x4]

champions suck in GM engines since .....1849 !!!

Since always!!

 

You remember 1849? lol

[Silverado4x4]

champions suck in GM engines since .....1849 !!!

 

Was just gonna say take those junk plugs out a stick with OEM.

[mawint]

To be honest, I have used Champions in GM engines before without issue. It was however a 95 bonneville with the 3.8, but that engine was temperamental on plugs also. If you ran Bosch in it, it would throw a fit while Champions ran just fine.

 

Since I'm not new to the whole this engine likes this plug better than the other, it doesn't surprise me that the ACD plugs work much better than the Champions. Without coming here however, I wouldn't have found out that GM changed gaps and I would still be diagnosing this thing. Even if this didn't solve my issue, it would have helped my peace of mind to know the plugs are now gapped to spec and I would have changed them anyways.