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Discussion Starter #1
Is this right? I always use NGK 6097's, usually with a .32 - .34 gap. I run methanol now so I gapped new plugs to .29-.30 and now I'm reading rich at normal driving conditions. It boosts great, but normal driving is around 11.5 AFR.

Idle is sitting at 10.2-10.6 even with the VPC leaned out at idle (just for testing).
It idles ok.

I used to run at ~14.7 under light throttle, now it's around ~12...
AFR o2 sensor is at the top of my downpipe, before the flange to midpipe. I didn't change anything but the PCV valve, new plugs and cleaned the coil packs.

Does this make sense? Either my car was firing wrong before, or these new plugs are firing too soon with this gap... in my head at least. Maybe I'm just paranoid and should be happy for the extra fuel? lol

-- Edit --

Oh yea, stock block/head, VPC, emanage, Profecb-ii, t-61, stock fuel system.
 
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Just to get a rise from you Bill.

I usually leave them at 12 accross the board.. but since I was getting a little hiccuping at idle, almost dieing and reading really rich, I just leaned out the idle knob to about 10:00.
 

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Adusting fuel would just mask the real problem so I wouldn't do that. It's way too rich, the O2 sensor and ecu should have the fuel fluctuating around 14.7 at idle and cruise as you probably know. Either the O2 has gone bad or you have a big enough vacuum leak making it overly rich to the point the ecu can no longer compensate. Plug gaps have nothing to do with it. Running that rich is eventually going to carbon up your plugs and the O2 sensor making things worse so it needs to be fixed. One other remote possibility is the vpc pressure sensor is bad, but it might be worth checking out.

Blinker fluid only controls how fast the blinkers flash so don't go changing that :)
 

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Might be a dumb question.. but when you say 02 sensor you are talking about the first primay sensor correct, not the one in the DP. Anyone have that link from awhile back with the write-up of how to check for vaccum leaks? My search button is broken ;) :D

I just want to know b/c my car is fouling plugs left and right, and is only BPU. Plugs gapped to .28 BTW Thanks in advance guys.
 

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Dan94TT said:
Might be a dumb question.. but when you say 02 sensor you are talking about the first primay sensor correct, not the one in the DP. Anyone have that link from awhile back with the write-up of how to check for vaccum leaks? My search button is broken ;) :D

I just want to know b/c my car is fouling plugs left and right, and is only BPU. Plugs gapped to .28 BTW Thanks in advance guys.

Primary sensor. Should be close to the turbo. Not the one underneath the car near the tail end of the trans.
 
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Dan94TT said:
Might be a dumb question.. but when you say 02 sensor you are talking about the first primay sensor correct, not the one in the DP. Anyone have that link from awhile back with the write-up of how to check for vaccum leaks? My search button is broken ;) :D

I just want to know b/c my car is fouling plugs left and right, and is only BPU. Plugs gapped to .28 BTW Thanks in advance guys.
When I said o2 sensor, I meant my aftermarket wideband. The primary o2 sensor is at the bottom of the midpipe. My wideband o2 is at the top of the downpipe.

I'll check for vacuum leaks, but something that big would be audible one would think.

I also noticed the car doesn't always idle that rich, usually only when warmed up. When the air was warmer out the other day, it seemed to idle a lot closer to 14.7.
 
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