FWIW, here’s my take after looking at the log file (have posted the log file in .xls format for viewing in Excel and rearranged some columns to aid in analysis).
Observations not in any particular order:
- TPS is not properly set nor is idle. TPS at idle shows to be 0.90v (should be less) while TPS%=46% which is way too high (should be 0%).
- Idle seems way high for a stock engine at 1000+. Properly setting idle and TPS will solve some things but that’s likely not the issue you’re seeing. At this point, not really sure what that is. Search for setting TBI idle.
- Before the alternator is “disconnected” at sample #972 (green line), things are clearly not right while it's "connected" regardless of whether in Open Loop (OL) or Closed Loop (CL):
- Idle RPM rises from 600 at 62*F to 1000+ at 130*F. Not right and just backwards of what should happen. RPm should drop as temp rises. Also, this takes 7 minutes (435 engine run seconds). Not right.
- BLM is 135 in OL before going into CL at sample #765 (blue line). Should be 128 in OL
- After entering CL, BLM rises from 135 to 159 and stays there, while INT changes slightly for a few samples and then locks at 128. Not right.
- Takes 15 min to go into CL. Not right.
- KPa is in low 40’s = seems too high for a stock engine running at 1000 PRM in P/N (= no load).
With alternator “connected”, it seems fueling is being improperly managed and/or reported by the ECM.
Then when the alternator is “disconnected” at sample #972, things seem to become normal:
- After disconnection, BLMs immediately drop from 159 to believable, slightly lean values in the low 130s.
- Also, note that kPa’s drop from low 40s to mid 20’s which is more believable at 1000 no-load RPM. So RPM stays the same at approx 1000 after disconnect, but kPa’s drop to mid-high 20s with no change in load. Not possible unless ECM being affected (by the alternator wiring???)
- IAC position now seems OK at mid 40s with the idle RPM. Should be much lower, but that will be fixed by properly adjusting idle and TPS.
- Throttle tap between samples 1077 and 1099 seems normal looking at the log.
- Battery volts drop to just over 12v from over 14v at sample #972. This seems normal as it is not uncommon for single volt alternators at idle or slightly above to require a certain higher RPM (1200+) to initiate charging in excess of 12v (see: http://www.powermastermotorsports.co...rnators.html#1). So, approx 12v at 1000 RPM seems right.
- Finally, it seems that the alternator is properly hooked up after you say you disconnected it. I’d check wiring. See also above link for details + additional searches.
So bottom line, all seems normal with the alternator “disconnected”. Do a log while driving it with “alternator disconnected” and describe what occurs.
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