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05 Chevy astro p300 and p1072

300 Views 1 Reply 2 Participants Last post by  AstroWill
broke down and took it to a shop for a 200 dollar diagnostics... they didn't come up with anything except doing a crank relearn with there fancy scanner and clearing the codes... bummer
also with the fancy shop tool they were able to tell me most of the misses were on 1 with some on 5...
fuel trims are still way negative aboout -10 but can go as high as -17
this makes me want to go check out the spider and the fuel pressure regulator and its the only thing i have not done.
Only problem is KOEO it holds 60psi for 20- 30 mins so i don't think there is a leaky injector or fuel pressure regulator...
My thought is that maybe under vacuum something is leaking/going wrong in there that doesn't happen KOEO...
Im a time crunch and need it tip top in about 3 weeks any and all suggustions welcome! THANKS!
For those just joining
P300 at highway speeds
p1072 -10 to -15 LTF on both banks now

New filter and pump KOEO 60psi for 30min before it slow starts to blead down
New cap, rotor, distributor, plugs, wires, coil, ignition control module
New mass air flow
New crank position sensor W/sim and relearn
o2 sensers 30k ago all read good on torque app

unplugged upstream cat no difference.
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Checked your air filter/intake?
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