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mwebb · 10-05-2010, 12:45 AM

at 694 rpm air flow = 5.37 gm/s
too high - these have a MAF sensor ? i thought they were speed density ?
if speed density , intake vacuum is too low
if MAF it would be a digital MAF .

STFT = -8% and LTFT = 0%

whenever i see a vortech engine subtracting fuel , i think INJECTOR
those injector assemblies with the built in pressure regulators leak in to the manifold .... common failure , hard to prove without test equipment

can you get misfire counters ?
both current and history , if yes , display them at hot idle - i bet they will flag 1 or more cylinders

hi HC is always misfire or cat converter or both
hi nox , restricted EGR or some cylinders can be lean because the 02 sensor corrects for total fuel trim , if you are subtracting 8% , the system is correcting for 1 or 2 rich or misfiring cylinders and the rest of the cylinders are getting the same correction
so they are lean

bad cat also is suspect for hi nox but you need to resolve the subtracting fuel at idle thing first

what software are you using ?

10-05-2010, 12:45 AM	#2 (permalink)
mwebb Master EcoModder Join Date: Jul 2009 Location: New York Posts: 513 no nickname , it's just a car - '04 volkswagen golf tdi Thanks: 2 Thanked 101 Times in 74 Posts	air flow too high at 694 rpm air flow = 5.37 gm/s too high - these have a MAF sensor ? i thought they were speed density ? if speed density , intake vacuum is too low if MAF it would be a digital MAF . STFT = -8% and LTFT = 0% whenever i see a vortech engine subtracting fuel , i think INJECTOR those injector assemblies with the built in pressure regulators leak in to the manifold .... common failure , hard to prove without test equipment can you get misfire counters ? both current and history , if yes , display them at hot idle - i bet they will flag 1 or more cylinders hi HC is always misfire or cat converter or both hi nox , restricted EGR or some cylinders can be lean because the 02 sensor corrects for total fuel trim , if you are subtracting 8% , the system is correcting for 1 or 2 rich or misfiring cylinders and the rest of the cylinders are getting the same correction so they are lean bad cat also is suspect for hi nox but you need to resolve the subtracting fuel at idle thing first what software are you using ?