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Jacked Up Fuel Trims w/Scan

Lawngoose

Lawngoose

New member
I went from a Front PLOG, and DP to headers last week.

Before I had good trims thanks to the MAF tune... but now I notice at idle my LTFT's are 16.4025 :(

So I figured that I maybe I need to do a VE Tune. When I unplug the MAF I get Lean results not pig rich like expected.

I abandoned the VE Tune for the moment, however when scanning... on WOT I lock in at 0 every time.

Should I just scale the %#@! out of the MAF for the idling frequencies? Or should I put a DHP BIN on there and completely start over?

EDIT: Recent scan added RACETRACK_10-27-2008_9_26_51_A from lawngoose -- Scan Depot dot net
 


I didn't look at the entire scan because it was just wayyy to long. However from what i picked up it's not just your idle trims that are bad. Your cruising trims are also out as well As for the idling trims i would scaled them 11% add obviously since they are positive trims and scale the cruising trims by 4. Don't forget to smooth everything out so you don't have a jagged mountain looking maf scale.

The trims aren't that bad fyi, i've seen worse. I don't know exactly how out they are when your idling since that's the max. I would definitely check for a vac. leak before you start messing with the tune though. It's not abnormal at all for the trims to be out that much, adding stuff throws everything off. When i moved my filter 5in closer to the maf my fuel trims went completely wacko. Just takes a little fine tuning and you'll be on your way back to wot tunes. And you'll enjoy the hell out of the headers.
 
One other member mentioned to me, that I could have a exhaust leak (which I believe, since its pacesetters) and fresh o2 could be getting to the o2 sensor.

My MAP(kPa) looks similar to other scans, so I think its ok, but I will double check all vac lines to be sure.

Thanks for the post!
 
Welded the pacesetters, fixed a small egr plate leak... reset trims.... still reading +16 on idle.

Next we plugged the exhaust to see if it would get richer... it did not.

The o2 sensor has already been changed once... and I do have a zzp extension harness.

Any ideas or suggestions?
 


Interesting.... that may be it. I am emailing them now.


EDIT: Got a reply back from ZZP, they advised me that the o2 extension I bought for my front o2 sensor will work.
 
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