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2B32 · 04-14-2017, 01:26 PM

I finally got my Sniper installed, starting & idling well with parameters within range according to the startup guide. Timing is 11° BTDC, IAC +/- 5%, Hot Idle bounces around 850 RPM +/- 30. I went for a test drive today and it seemed to be running well until the engine reached about 175°. After the engine got hot it started cutting out/sputtering/lurching under acceleration. If I kicked in into neutral it seemed to smooth out, but I would have to rev the engine much higher than normal and ease the clutch real slow to take off again. Even then it would cut out/sputter/lurch to get going again; it even died a couple of times. On restart, it would crank but it would not fire up right away like it did cold, and I would have to depress the gas pedal slightly to get it to fire (to my understanding I should not have to do that with EFI). I let it sit and cool off, then repeated the process a couple more times. I have a datalog of my last drive, but I don't know how to read the data (I know how to access the data, but I don't know what any of it means). Every time I try to upload the datalog here I get an "invalid file" error message.

Any Ideas what could be causing my acceleration issue and hard hot start?

04-14-2017, 01:26 PM	#1
2B32 Registered User Join Date: Jun 2015 Location: Northeast Missouri Posts: 71	New to Holley Sniper, Anyone With Experience? I finally got my Sniper installed, starting & idling well with parameters within range according to the startup guide. Timing is 11° BTDC, IAC +/- 5%, Hot Idle bounces around 850 RPM +/- 30. I went for a test drive today and it seemed to be running well until the engine reached about 175°. After the engine got hot it started cutting out/sputtering/lurching under acceleration. If I kicked in into neutral it seemed to smooth out, but I would have to rev the engine much higher than normal and ease the clutch real slow to take off again. Even then it would cut out/sputter/lurch to get going again; it even died a couple of times. On restart, it would crank but it would not fire up right away like it did cold, and I would have to depress the gas pedal slightly to get it to fire (to my understanding I should not have to do that with EFI). I let it sit and cool off, then repeated the process a couple more times. I have a datalog of my last drive, but I don't know how to read the data (I know how to access the data, but I don't know what any of it means). Every time I try to upload the datalog here I get an "invalid file" error message. Any Ideas what could be causing my acceleration issue and hard hot start?