Trying to tune MAF. Indicates rich when scanning, adjust MAF and still rich.
I have a 04 GTO 5.7 with a Texas Speed 227/234 .600"/.600" 114 LSA 111 ICL. I'm trying to tune the MAF and it always indicates rich with a lambda of 0.75-0.80 around idle and increases as MAF hertz increase. I'm working off of a stock tune setup for MAF tuning. I logged and multiplied by the full percentage because of the 10-20% MAF eq error. The second tune will show just as rich when logging. The 3rd is the same too. By the 6th when multiplying by the full percentage it will barely run (if I multiply by half % it will take 12 attempts). As I'm going through the process of tuning the MAF I noticed the car is getting slightly harder to start with each new tune loaded starting with either the 3rd or 4th attempt. When this is happening I start the car and see 1.3-1.5 lambda. After the car runs for a couple of seconds it suddenly swings back to the 0.75-0.80 range at idle. It's like the MAF changes are only changing fueling for the first couple of seconds after start up. The car runs smoothly so I don't suspect a plug or wire concern. Fuel trims aren't pulling fuel when fuel trims are enabled so I don't think I have an injector issue. Any thoughts?
I set the file up a while back and I was most likely setting up a VE tune too at the time. I'll deal with that and see what happens. It makes sense that it would be running for a few seconds on the MAF then fails and then runs super rich afterwards.
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