c5 issue

[HemitheKat]

run down:
2002
auto
3200 vig stall
stock short block
g5x3
afr 205 heads
60lb inj
bbk intake
bbk TB
cold air kit
runing on SD relocated IAT

issue is if you look at the scan at about 3min into it the afr drops to 12.0 for no reason that i can see. does not lean out at all during PT driving. fuel pressure is steady, inj pulse width stays the same, there are no adders enabled, map stays the same as it drops. any input??

[Bill@HPTuners]

weird, can't say I have an answer for you but I will give you a tip, when you disable STFT & LTFT you really have no need to log them in the scanner as all they do by doing so is have slowed your frame rate down from 10fps to 5fps.

I wonder if its an issue with your injector sizing tables, its rare you'll see NA applications running 60+lb injectors as you'd probably need to be making 700hp NA to actually need that large of an injector off the top of my head.

[5_Liter_Eater]

Thats a weird one. NB O2 mV's increase also which would indicate to me that it's not a problem with the WB sensor.

[HemitheKat]

yep it's a tough one, for the hell of it i just put on the stock inj and had the same results.

[HemitheKat]

tried using the vcm controls/afr control to make the afr 14.7 but it did the opposite went down to 11.5 and this is still with the stock 28lb inj. i also tired changing the software from the 2.2 update back to the 2.1.18 and had no effect. just trying to see if it was something in the software.??

[Proven Power]

I am tuning g5x3 cam also timing at idle was frist issue #60 injectors to big will cause problems could not get engine to lean always rich burn your eyes rich went down to #40 injectors and found more problems now

[HemitheKat]

I am tuning g5x3 cam also timing at idle was frist issue #60 injectors to big will cause problems could not get engine to lean always rich burn your eyes rich went down to #40 injectors and found more problems now

are you using 2.2 software?

[HemitheKat]

nobody?

[WS6FirebirdTA00]

does it happen every time at 67ºC ECT? Also, you are running some very low timing in there for that cam at idle. What is the IAC doing at this time?

Does it stay like this the rest of the time? Maybe your air pump on at startup is causing it to be lean.

[HemitheKat]

does it happen every time at 67ºC ECT? Also, you are running some very low timing in there for that cam at idle. What is the IAC doing at this time?

Does it stay like this the rest of the time? Maybe your air pump on at startup is causing it to be lean.

ect doesn't matter it happens at different temps. timing iac isn't changing my fuel and once once it afr drops it doen't recover back to 14.4. airpump is not enabled and its not on the car.

[WS6FirebirdTA00]

I know on my car that after a certain point on startup (mainly hot restarts) the AFR will take a step down back to normal. Only thing is my lean condition is about 16:1 or more when it was happening.

[HemitheKat]

so what else effects actual afr than the commanded besides ve

[WS6FirebirdTA00]

OLFA, PE, and all the startup adders.