smilexelectric
Full Access Member
Whatever the gap said on the fan shroud when I changed them. Which I believe was .035.
Cylinder 6 misfire
- Thread starter smilexelectric
- Start date
Check under your cap. If you changed it recently, it's possible you didn't get it seated just right and have moisture and c0rrosion in there.
smilexelectric
Full Access Member
Don't understand how it wouldn't be seated right. Their are 2 screws that have to be lined up right to be able to screw them in.
Kennyray
Full Access Member
Doesn't mean anything, they can still go on crooked.
Texas Jim
Texas..It's a Whole 'nuther Country
If the misfire is only on number 6... check the wire from end to end...
Make sure it is plugged into the distributor real good and make sure it is all the way down on the spark plug.
Also check the wire to see if it has touched the exhaust manifold.
If the plugs are gapped at .35... I think that is too small of a gap.
I believe that they are supposed to be at .60 if they are Platinum plugs... and .45 if they are "NOT" Platinum plugs.
I would highly recommend to use AC Delco Platinum plugs in it.
If it is gapped to .35... it may have fouled out.
You may need to pull that plug and check it.
Make sure it is plugged into the distributor real good and make sure it is all the way down on the spark plug.
Also check the wire to see if it has touched the exhaust manifold.
If the plugs are gapped at .35... I think that is too small of a gap.
I believe that they are supposed to be at .60 if they are Platinum plugs... and .45 if they are "NOT" Platinum plugs.
I would highly recommend to use AC Delco Platinum plugs in it.
If it is gapped to .35... it may have fouled out.
You may need to pull that plug and check it.
smilexelectric
Full Access Member
Checked the dizzy and all wires to each cylinder none are burnt or anything like that. Everything is in place and snug fitting.
junior3815
Get 'em, Got 'em, Good
CHECK THE PLUGS!!
A while back GM changed the recommended gap. Most vehicles went to a smaller gap, down from .060". I don't know how far back in model years the recommendation goes.
GM manual I looked in shows plug gap for the 4.3 to be .045." Online parts stores show .060"
Edit:
Here's the info about smaller gap, but doesn't apply in this situation. Only 4.8L and up
Subject: Information on New Spark Plugs and Gapping #03-06-04-060 - (10/24/2003)
Models: 2004 Buick Ranier
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)
--------------------------------------------------------------------------------
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 1.01mm (0.040 inches) when the spark plug is made. 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 manual I looked in shows plug gap for the 4.3 to be .045." Online parts stores show .060"
Edit:
Here's the info about smaller gap, but doesn't apply in this situation. Only 4.8L and up
Subject: Information on New Spark Plugs and Gapping #03-06-04-060 - (10/24/2003)
Models: 2004 Buick Ranier
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)
--------------------------------------------------------------------------------
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 1.01mm (0.040 inches) when the spark plug is made. 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.
Last edited:
Kennyray
Full Access Member
That could with any GM from that era or earlier. I still think he need to get rid of the Autolite plugs. GM motors don't like them. I have had fouling problems with them in the past in a GM motor and always on one cylinder. I'll bet #6 is a weak cylinder.
