New sparkplugs/air filter = bad mileage
Jan 18, 2007 | 08:50 AM
#21
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From: Connecticut (NY State of Mind)
There has been some discussion on the necessity of gapping dual electrode plugs. I installed some new plugs and the factory gap was in the .03_ range. I decided to leave the gap as set by the factory. My gas mileage has not been what it should so I just recently regapped to .04ish - more akin to the .044 spec. The jusry is still out on my gas mileage right now.
There is no good reason not to gap the plugs close to spec.
There is no good reason not to gap the plugs close to spec.
Jan 18, 2007 | 09:04 AM
#22
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From: Smoky San Diego
The factory plugs come out of the box at .034 and the factory specs recommend .043 or .044
I'm thinking that the sparkplugs for the 3.4L are used in different engines so that's why they manufacture the plugs with a .034 gap. Can anybody confirm this?
I'm thinking that the sparkplugs for the 3.4L are used in different engines so that's why they manufacture the plugs with a .034 gap. Can anybody confirm this?
Jan 18, 2007 | 11:14 AM
#24
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From: Siletz,Oregon
the negative one..... on a side not when i replaced my plugs in my truck for factory denso's i didint gap them and it runs like a champ and gets atleast 21mpg
Last edited by Elton; Jan 18, 2007 at 11:15 AM.
Jan 18, 2007 | 12:13 PM
#26
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From: Montreal, QC Canada
I have always installed them straight out of the box and never had any issues. Also keep in mind the gap grows as the plugs wear so being a little on the small side isn't bad either.
Jan 18, 2007 | 12:55 PM
#27
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From: NorthWest NJ
upon installation of mine i check the gaps, made sure they were good, some were off by a bit some by a decent margin, gapped em, and put em in, its really not that hard to gap em, takes 5 minutes max for all six
Jan 18, 2007 | 03:39 PM
#29
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Well, obviously there may be an anomaly here and there (pehaps in manufacturing supply, perhaps they had been changed at the dealer prior to delivery, etc). I would still maintain that if you have Densos on one bank and NGKs on the other, you're probably dealing with the original plugs on the vehicle.
Well, I wouldn't go as far as saying that isn't true; I had the same exact thing and I've heard of others having a 50/50 of Denso/NGK plugs from the factory...for instance, my '96 had Denso plugs on one side and NGK on the other. They were original...pretty much everything was original, actually, when I bought it....10 years after it was made 
Jan 18, 2007 | 03:52 PM
#30
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From: Connecticut (NY State of Mind)
ALso remember that with the dual electrode, the plugs should wear half as fast as single, as there is only one spark per firing. It takes a bit of time to wear them down when the engine is running right.
Jan 18, 2007 | 04:14 PM
#31
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From: Montreal, QC Canada
.....not as good as iridiums, but light years better than a standard single electrode plug.
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