Tuning question/Running lean 650-680


New Member
Sep 19, 2006
I recently added some upgrades like:
TT 95 octane street chip
HP fuel pump/hotwired
42lb inj.
Accufab adj fuel regulator set to 43 lbs(vac line off)
Stock Turbo set to 16-18 lbs(aftermarket guaged)

Car already had headers,CAI and test pipe in

My O2 readings are in the 650-680 range when I get on it. Seems to me, the 650-680 range is lean, but don't know if it could be fuel (from the chip I just had made) ulnless I need to change the fuel FILTER or maybe even my spark plug gap??? Seems that it shouldn't be a fuel delivery issue as I have just upgraded the fuel stuff(all but the filter). Thanks guys
Now you know whats coming right? Change the filter! :biggrin:

Also has the weather gotten alot cooler where your at? Colder weather tends to need more fuel.

Who's chip? Is it adjustable?
Also make sure the MAF reading is at 255 (or close to it) when at full boost. The MAF is "AF" on the scanmaster.
Hi Eric,
You burnt the chip for me w/42 lb inj.! Install was easy. I installed the Adj fuel guage, pump and injectors and the chip. I'll change the filter next and look at the MAF numbers(AF). I'll let you know tomorrow what happens. Thanks a bunch!!
Also, while U R looking.. take a look at the FP and see if it's keeping up w/ the boost increases.