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Discussion Starter · #1 ·
I seem to be over fueling right now, the exhaust smells a bit like it and has some white smoke (not wet, and I’m not loosing coolant before we go down that path)..

Here is the setup
Stock engine (intake, MAF, chip, etc)
No air intake side leaks (which would lean it out really)

NO CATS..
free flow muffler

This seemed to have started when I rebuilt the exhaust system so I’m thinking a lack of back pressure (?)..

I’m running 7 degrees advanced, plugs have 10k or so on them wires are new, coil 10k miles...


No tune resistor in a NAS truck that I know of so I can’t just go to the Saudi engine map spec.

Think advancing the ignition will help? I was thinking of bumping it up to 10 degrees and see from there.

It does occasionally lightly backfire when shifting up (indicates over fueling)

Thoughts?
 

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Boy, have you checked the oxygen sensors with your rover gauge? Also you can adjust the MAF to supposedly lean out idle, also the tune resistor is illusive but will help w/o catalytic convertors
 

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Discussion Starter · #3 ·
humm,
i'll plug it in tonight and see but as i recall the rover gauge can't make any changes and i am not throwing codes.. but then again the ECU is pretty stupid i could have an O2 out of range i guess - which would be funny now that i am not killing them with my drive shaft (why i went ahead and built the new exhaust)

how would you go about tuning MAF? I do have a spare new one, maybe i'll throw on and see if that changes anything - maybe just dirty (dunno)
 

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Clowns have snuck into the engine bay and turned up the fueling.
 

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Discussion Starter · #6 · (Edited)
Humm I’ll recheck that but it runs fine

Checked, not it...
 

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Sounds like you have the O2 sensor wires crossed or a bad O2 for that matter. 1 bad O2 will wreak havoc on a 14CUX system...2 bad O2's will get you high as a kite on fumes. Omitting the cats has zero effect on what you are describing. Check those items before you start Dicking with the MAF.
 
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