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Changed Plugs = Fuel Consumption Increased by 15%... HELP!!!

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Old Jun 20, 2007 | 11:05 AM
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Default Changed Plugs = Fuel Consumption Increased by 15%... HELP!!!

Hello All,

I've just changed my 04s spark plugs with OEM ones.
Mileage is 20,000 miles.
Fuel consumption has shot up by 15%.

Should i change back to old plugs?

Don't have any Nissan dealerships catering to Zs in the country that i live in.

HELP!!!
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Old Jun 20, 2007 | 11:13 AM
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Double check the part numbers to make sure you didn't get plugs for another car, where the plug gap would be different. Double check the connections on your coil packs as well.

Do you notice your engine running rougher than usual?
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Old Jun 20, 2007 | 11:18 AM
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Originally Posted by jtabraham
Double check the part numbers to make sure you didn't get plugs for another car, where the plug gap would be different. Double check the connections on your coil packs as well.

Do you notice your engine running rougher than usual?

Thanks for the response...
The part numbers are the same..
Coil pack connections.. will check..

Engine is slightly rougher in higher revs..
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Old Jun 20, 2007 | 11:26 AM
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Bad plugs perhaps?
The plugs that you took out were OEM ones and your replacing it with OEM ones right?
Peace!
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Old Jun 20, 2007 | 12:16 PM
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why are you changing plugs that early in the mileage?
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Old Jun 20, 2007 | 12:19 PM
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Tell us about driving the Z in Pakistan
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Old Jun 20, 2007 | 12:34 PM
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Why did you change the spark plugs at 20k miles ?

They're supposed to be good until 105k miles...
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Old Jun 20, 2007 | 04:04 PM
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Sometimes an ECU reset will cause increased fuel consumption until it relearns the proper fuel trims... give it another tank of gas before deciding something is wrong...
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Old Jun 20, 2007 | 08:06 PM
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Originally Posted by Kolia
Why did you change the spark plugs at 20k miles ?

They're supposed to be good until 105k miles...
mine were fouled after 45k miles. An this was with a stock car.
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Old Jun 20, 2007 | 08:08 PM
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Originally Posted by jtabraham
Double check the part numbers to make sure you didn't get plugs for another car, where the plug gap would be different. Double check the connections on your coil packs as well.

Do you notice your engine running rougher than usual?
+1 You need to check the gap on the new plugs. I think stock gap is like .043.
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Old Jun 20, 2007 | 09:47 PM
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Originally Posted by zheartroad
mine were fouled after 45k miles. An this was with a stock car.

yeah +1 mines were poop at 30k the Z eats plugs real easy
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Old Jun 21, 2007 | 03:16 AM
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Originally Posted by gabez33
yeah +1 mines were poop at 30k the Z eats plugs real easy
that is true...my first set i changed out at 40k and they were fried...i changed them out again to another set of iridiums and they were actually still good...the car will run rich a little until it relearns...
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Old Jun 21, 2007 | 04:41 AM
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Very interesting. I'll have a look at my own plugs then.

The engine tone has felt a bit weird under loading in the past months...
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Old Jun 21, 2007 | 05:14 AM
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Try to do a ecu reset. Look at your exhaust and see if there is alot of black crap. Clean the tips - drive and look agian. If it has a gas smell and alot of black then one of the plugs might be bad or not firing.
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Old Jun 21, 2007 | 05:19 AM
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hey travis feel like turning a wrench on a tt install???
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Old Jun 21, 2007 | 06:47 AM
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PMed you
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