Ive been running a Holley Sniper for a about four years now. In the last year I have been struggling to fix a consistent hesitation I get under acceleration after it warms up. After this starts, it also develops a problem idling, by surging and slowing until it stalls. If I take a ten mile drive, it might not start giving me a problem until I am over half way through the drive or more.
Set up:
Chevy 350 w/ MSD ignition Street Fire CDI. New plugs and wires. Tanks INC EFI fuel tank and pump. All 4 years old with less than 1000 miles.
Here is what I have done so far:
- Sent data log to Holley. They didn't see anything but suspected a bad ECU, so I sent in the whole thing in and they rebuilt it for free (kudos Holley).
- Found and repaired an exhaust leak upstream of the O2 sensor at the manifold donut.
- Replaced all plugs, Ohm tested all plug wires
I have ordered a new O2 sensor since idling and acceleration are my two trouble areas.
Iv'e surfed the Holley forums, but it descends into pouring over data logs and AF/R numbers and I don't understand why I would have to tweak settings on an engine that ran fine for three years, this seems more like a component failure. The nature of the hesitation feels more like gas than spark. Especially obvious when it can't idle. Its sort of like vapor lock, but I drove this car for three years in Texas summers with no issues.
Any ideas on where I should go next if the O2 sensor doesn't help? Coolant sensor? Of do I have to start posting my data logs on the Holley Forum??
Set up:
Chevy 350 w/ MSD ignition Street Fire CDI. New plugs and wires. Tanks INC EFI fuel tank and pump. All 4 years old with less than 1000 miles.
Here is what I have done so far:
- Sent data log to Holley. They didn't see anything but suspected a bad ECU, so I sent in the whole thing in and they rebuilt it for free (kudos Holley).
- Found and repaired an exhaust leak upstream of the O2 sensor at the manifold donut.
- Replaced all plugs, Ohm tested all plug wires
I have ordered a new O2 sensor since idling and acceleration are my two trouble areas.
Iv'e surfed the Holley forums, but it descends into pouring over data logs and AF/R numbers and I don't understand why I would have to tweak settings on an engine that ran fine for three years, this seems more like a component failure. The nature of the hesitation feels more like gas than spark. Especially obvious when it can't idle. Its sort of like vapor lock, but I drove this car for three years in Texas summers with no issues.
Any ideas on where I should go next if the O2 sensor doesn't help? Coolant sensor? Of do I have to start posting my data logs on the Holley Forum??
