jeremy.yeager81

Hoping someone here can point me in the right direction. 2000 Astro RWD with the 4.3L and 98k miles on the clock, been sitting for the last 7 years without being started. Here is what was done so far, then i will add the current scan tool data. Every part that has been replaced is with AC Delco recommended equipment. Here is the simplified version of work completed thus far

1. new battery and oil change, no fuel pressure on test
2. new AC Delco fuel pump and filter, starts, barely runs, fuel pressure steady at 65 PSI and holding. Tank was drained, no trash in it
3. new AC Delco plugs, wires, cap rotor Check for excess lash in the distributor, no issues
4. Idles much better, P0304 code, bad spark knock, flashing MIL under load. Confirm spark cylinder 4
5. Replace CPFI with upgraded AC Delco MPFI conversion, spark knock cleared, now have a P0300 with flashing MEL under load
6. smoke test for vacuum leaks, all clear, tear down again to confirm all injectors are correct, test again for vacuum leaks-none

There has been Seafoam in the gas tank, Marvel Mystery Oil in the oil and some starting fluid to get her running at first

There are no other codes showing. here is the data captured on the scan tool at idle

ABSLT TPS 0%
RPM 604
CALC LOAD 3.1%
MAF 0.71%
MAP 11.8 HG
COOLANT 192F
IAT 95F
IGN ADVANCE 22.5
ST FTRM1 0.0
LT FTRM1 9.4
ST FTRM2 0.0
LT FTRM2 7.8
SPEED 0 MPH
FUEL SYS1 OPEN
FUEL SYS2 CLOSED
02S13(V) 0.080
O2S21(V) 0.795
ST FTRM21 1.6%
PTO STATUS Dise

Any direction will help. Again, the only codes that have shown have been a P0304, then a P0300 after replacing the spider

kevinkpk

With what I read, if you can keep it running for 1/2 hour it might clear up, again, great post just not sure of the run duration.

jeremy.yeager81

10-4, it has about 2 hours idle, roughly 20 driving miles on it. I just get nervous pushing it on the road. Really don't want to be replacing the cat next. I will say that the fuel trim leveled off considerably. it was 20%+ on both banks for a while and that did calm down with some driving. I know the van was running like a champ when it was parked, Close friend of mine used it as a work van since it has a cage, shelves and ladder rack. He just got out of the business and forget to start and move it until it was too late

jeremy.yeager81

How is this for dumb, crossed wires on 3 and 5. Took 60 seconds on the Tech 2 scan tool and $40 to find out that dumb mistake. Runs like a champ now. Derp