It ran like this before I changed the pump and spider injectors. I don't want to have to change the pump again. It was a real PITA.
No codes stored or active. I have Scan XL and can do real time data logging.
2nd gear is when it is the worst. If I downshift to second at 40ish it really lays over. I have nothing until it gets to about 55 and then picks up a little.
Low rpms are the worst. I have to ease into the throttle. If I just mash it to the floor it just lays over. If I ease into it there is a point at about 3/4 throttle that it picks up.
I have run the TPS test a bunch of times and don't see a dead spot on the DMM and my scan program shows a smooth curve up to 4.5 volts.
More help than you think. Sometimes you just have to talk it out with someone. I didn't know about PE mode. What does PE stand for?
Thanks
Sorry PE mode, stands for Power Enrichment mode. AT low throttle engine warm, you are in closed loop reading teh O2 sensors, open loop running 100% NOT using O2 sensors. When hat and you nail teh throttle, the engine needs more fuel so a PE Mode table is read and O2 sensors are ignored. For that short time the engien is in Open Loop/PE mode, or replying on MAF PCM table input for WOT fueling. You dont have to be at WOT, there are a bunch of qualifiers that need to be met before PE mode is entered, such as TPS%, temp, rpm etc and time.
Now, the 2001-2002 Vans with Vortec 350 have the more advanced 512kb dual 80 pin connectors PCM with the last 4 digity sbeing 0411. This PCM was used with your GEN 1E Vortec 350, but also in some Vettes, Camaros, trucks. This is special because the Vortec 350 uses a 4x reluctor(or every tim ethe crank spins 1 revolution, the Crank Position Sensor0CKP sensor is triggered 4 times. Now in the GEN 3 engines they use a 24x reluctor so 24 pulses per crank rev. This is important for those who want to do a 4x to 24x conversion on the Vortec 350 which can allow the newer 8 coil Coil Near Plug ignition, instead of the Vortec 350's single coil/distributer setup.
Big clue that the issue was there before your did the spider upgrade and fuel pump swap.
Sometime when its dark, start the truck, shut off the headlihghts and look around teh plug wires and distributercoil ofr arcing. I could actually hear the coil snapping when it was failing, new coil all better. I suppose you would have to pull the doghouse to check out the coil/distributer.
FYI If you think you are flooded, hold down the throttle wide open and then crank. So long as the TPS is WOT the injectors wont fire thus clearing the combustion chambers.
Also check the under hood fuse box for a blown ENG B fuse.
I just had a thought, this all could be an upper intake leak as well. I did some work and the seal around teh throttlebody pinched and it wouldnt run right.
So much stuff I have had with tehse L31's.
The intermittent part is a bitch though.
peace
Hog