Any Suggestions?

[RBruton]

I'm throwing this out there to see if any have any suggestions. I'm running into a lean situation with the following readings on my scanmaster. After the motor has gone into closed loop the INT is reading 128, the BL is 150 and the IAC is 00(these readings are steady). The TPS is set at .44. I am getting retard readings just building 5 psi of boost of 3 or more points and more if I stay in it alittle longer. I am running 93 octane plus alcohol injection that I rarely even get into because I back out of it when I the scanmaster showing some retard. I have tried increasing fuel pressure even to 50 psi with no improvement. I even tried some 100 plus octane with alcohol and am still get similar retard building 5 psi of boost. I am not getting any retard on the knock guage. I first thought it might just be a false reading because the exhaust or down pipe vibrating in the firewall or frame but that still doesn't explain the readings on the scanmaster. I have been told that when the BL is above the ideal 128 +/- 5 that a lean situation is detected and the computer is adding fuel I have been told its possibly a vacuum leak or chip has gone bad or possibly my fuel pressure gage is not giving me an accurate reading. I am going to change to my racing chip, run some 114 octane through and see if anything changes but I just can't put my finger on it just yet. Any replies would be appreciated.

 

[suicide six]

Knock Problem Check List
1. Start-up knock? Normal and usually caused by the starter engaging the flex plate. Usually sets off 1-3 lights.
2. Possible bad ECM or ESC module. Test with good working units.
3. Exhaust rattle – check the down pipe, tail pipes, and have engine tie down strap
4. Boost creep especially top of 1st gear on 1-2 shift.
5. Lean air/fuel mixture.
6. To low octane gas – bad pump gas – try some race gas
7. Too much timing in chip for fuel used. Try different chip.
8. Try cooler spark plugs – use only AC Delco (R43-TS or R42-TS)
9. Gap plugs to .035
10. Check torque converter bolts to make sure they are tight
11. Loose harmonic balancer. Make sure torqued to 200 ft/lb Is keyway secure?
12. Check internal engine noises like timing chains (roller), lifters/rockers, etc.
13. Damaged knock sensor
14. Check fuel pump pressure and volume
15. Proper torque on knock sensor – 14 ft/lb
16. Check Alternator voltage: 13.8 - 14.5v
17. Check computer power wire - they can break internally.
18. Troubleshoot the computer connector power wires and ground wires.
19. Swap coil pack, wires, plugs w/known good units.
20. Swap MAF with known good unit.
21. Check battery ground connection @ block (clean/inspect).
22. Check/change battery cables (both).
23. Are there MAF leaks in the inlet tube?
24. Are there vacuum leaks. Use carb cleaner or WD-40 & spray everything. Does the rpm change?
25. Disconnect the main injector harness - inspect, WD-40. Check for moisture in main connector.
26. Disconnect the coil-pack connector - inspect pins & spray w/WD-40.
27. Is the cat still installed? Is it good?
28. Have you performed a leak down check?
29. Do the rockers open/close? Do we have a wiped cam lobe?
30. Is the boost/vacuum steady @ idle?
31. Is the engine over revving? Should be 4,800-5,200 rpm
32. Carbon in cylinders? Clean with GM engine top cleaner
33. Inter-cooler dirty? Clean inside inter-cooler and fins
34. Oil in intake tract?
35. Check for exhaust leaks, cracked header
36. Battery good?
37. EGR valve in working order?
38. Check that no cables, wires, etc are touching the knock sensor
39. Blown head gasket? Compression test. Should be around 150.
40. Injectors flowing/working correctly?
41. Check vacuum line to fuel pressure regulator for cracks
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[RBruton]

Thanks Suicide Six for the reply, looks like I have my work cutout for me