Any ideas on what is making this car go lean?
#1
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Any ideas on what is making this car go lean?
I tuned this car and I'm getting some strange behavior. You'll notice in both images that there are 10-15* sweeps in CLT temp (195-208*), TP is static, RPM is static, but AFR is going lean. Any thoughts on what to adjust?
#4
The only variables that do not stay constant during the lean spike are the AFR's and coolant temp. So either excess air is getting in (vacuum leak, even a very minor one can cause this....ask me how I know) or fuel that should be going in is either leaking or blocked but I have no idea how that would happen randomly.
#5
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When these sensors have a short, they typically give crazy readings like 500*, right? Ever see a bad sensor act like this? I haven't but I'm running out of ideas and I want this guy to be able to track his car sow I can show him the error in his supercharger ways. lol
Actually he missed the MSR-C track weekend because of the funky EFI behavior like this and he deserves better.
Actually he missed the MSR-C track weekend because of the funky EFI behavior like this and he deserves better.
#9
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Most of that is static but filtered. That slight amount of TP, even if not filtered, should not create a 1ms PW adjustment. If you look throughout the log you'll find that small amount of TPaccel does not cause AFR to go lean.
#13
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Can I please get some thoughts on this log regarding CLT, MAT, and BattV behavior on this supercharged car? I'm not sure if I'm chasing bad sensors, bad wiring, or something else. Please also review TP vs. TP dot and it's peculiar behavior. TPSdot threshold is set to 220%/s so I'm not sure why it's triggerting from 894-902s in the log.
Thanks.
Thanks.
#15
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I really want to help this guy out, he's been struggling for a while. Time to start replacing sensors or what?