Engine won’t start -good spark and fuel

[txboiler]

I have just shy of 100miles on BPE 347 with Sniper EFI. Had it out last weekend for an other short Confidence run around town (approx 10 miles). Pulled it into the garage and let it run for about 30-45 sec until I turned it off. Went to start it the next day and it cranked but did not start, normally it starts right up. I turn the key back to ign on and heard the fuel pump run and tried to crank it again for about 3-5 seconds before it finally started. It ran about 2-3 seconds before it died. Tried starting again and it did, ran rough, and I gave it a little gas and it died. I got out and checked engine for any obvious loose connections etc, none noted. I tried starting again this time with hood open and it started but rough and I noticed a white “cloud” come out intake (it was not smoke and smelled of fuel).

I pulled a plugged and checked it, it is dry and has blue spark.

I have called BPE and they are supposed to call me back this week.

I didn’t want to start checking timing etc as I changed nothing after the previous successful drive.
Looking for any suggestions.

[65 Cobra Dude]

Maybe a bad load of fuel?

Henry

[Papa]

Are you sure the distributor bolt was tightened? If not, it could have let the distributor move and your timing could be off.

[Railroad]

If you think it is rich/ flooding on start up, you might try holding the throttle wide open while cranking.
On fuel injection this normally shuts off the fuel and gives the engine time to clear up.
When it starts, let up on the throttle and let it idle. Hopefully it will clear up and idle normally.
I had this happen on a TB fuel injection. The injectors were leaking into the engine after shut off.
After a short shutdown the engine would be flooded. Long shut downs things evaporated off.
I ran some continuous tanks spiked with cleaner, all seems right.

[Papa]

If you think it is rich/ flooding on start up, you might try holding the throttle wide open while cranking.
On fuel injection this normally shuts off the fuel and gives the engine time to clear up.
When it starts, let up on the throttle and let it idle. Hopefully it will clear up and idle normally.
I had this happen on a TB fuel injection. The injectors were leaking into the engine after shut off.
After a short shutdown the engine would be flooded. Long shut downs things evaporated off.
I ran some continuous tanks spiked with cleaner, all seems right.

To add to Henry's response, the Sniper (assuming that is what you have) dumps a ton of fuel into the engine when starting cold. This caused me to foul plugs several times before I realized what was happening. The Sniper is also hypersensitive when running without the side pipes, which I belive caused the Sniper to think it was lean and caused it to dump even more fuel into the engine.

[John Ibele]

I don't know if BPE ships their engines with their own tune (what Holley calls a 'Config' file). If so, the call to BPE is the right place to start.

If they ship with one of the standard Holley configurations loaded and you haven't changed anything, you've got a very rough tune. And quite likely running rich, as Papa said.

If you don't have the Holley cable to hook a laptop up to the Sniper, I would start a datalog on the handheld, crank the engine and let it run for as long as it can or up to 30 seconds or so, take the chip out of the handheld and pop it into my computer, and look at the datalog in the Sniper software. There you can open the datalog and pull up a large number of parameters which can tell you what the Sniper was seeing and doing while the engine was running (rough).

You may know this, but for others less familiar with the Sniper, it 'self-tunes' in only one respect: it populates a 'learn table' under certain operating conditions based on its comparison of the actual air-fuel ratio (AFR) gathered from the wide-band O2 sensor to the desired AFR stored in the AFR table. The learn table is always used to adjust the base fuel table to determine how much fuel is injected into your engine. Everything else is set by the user in the config file, including the desired AFR, the spark timing, cranking fuel, after start adjustments, temperature adjustments, idle adjustments ... too many more to list here. So it shouldn't be considered self-tuning. And for most, spits out enough extra fuel to make your eyes water with the base configuration.

I am pretty far down the engine tuning journey with the Sniper. So I could share a bunch more, but don't want to assume you don't already know it all or that you would want to read it. But happy to share here or in a PM if desired. Good luck.

[txboiler]

Railroad thanks for the suggestion of holding wide open during start. I was not aware of the feature, on Holley Sniper, you mentioned.

[txboiler]

To add to Henry's response, the Sniper (assuming that is what you have) dumps a ton of fuel into the engine when starting cold. This caused me to foul plugs several times before I realized what was happening. The Sniper is also hypersensitive when running without the side pipes, which I belive caused the Sniper to think it was lean and caused it to dump even more fuel into the engine.

Papa. Thanks for suggestion about side pipes and distributor bolts. I will need to check the distributor when I get back in Town later this week. The side pipes have been installed for last 100 miles while doing confidence runs.

[txboiler]

I don't know if BPE ships their engines with their own tune (what Holley calls a 'Config' file). If so, the call to BPE is the right place to start.

If they ship with one of the standard Holley configurations loaded and you haven't changed anything, you've got a very rough tune. And quite likely running rich, as Papa said.

If you don't have the Holley cable to hook a laptop up to the Sniper, I would start a datalog on the handheld, crank the engine and let it run for as long as it can or up to 30 seconds or so, take the chip out of the handheld and pop it into my computer, and look at the datalog in the Sniper software. There you can open the datalog and pull up a large number of parameters which can tell you what the Sniper was seeing and doing while the engine was running (rough).

You may know this, but for others less familiar with the Sniper, it 'self-tunes' in only one respect: it populates a 'learn table' under certain operating conditions based on its comparison of the actual air-fuel ratio (AFR) gathered from the wide-band O2 sensor to the desired AFR stored in the AFR table. The learn table is always used to adjust the base fuel table to determine how much fuel is injected into your engine. Everything else is set by the user in the config file, including the desired AFR, the spark timing, cranking fuel, after start adjustments, temperature adjustments, idle adjustments ... too many more to list here. So it shouldn't be considered self-tuning. And for most, spits out enough extra fuel to make your eyes water with the base configuration.

I am pretty far down the engine tuning journey with the Sniper. So I could share a bunch more, but don't want to assume you don't already know it all or that you would want to read it. But happy to share here or in a PM if desired. Good luck.

John. Thanks for all this information. I will DM you more on the tuning process. I have been ready up on this and is something I have been hesitant to jump into this but realize it is a necessary part of this journey.

[Jeff_J.]

Lot of good suggestions here. I would have checked the coil as well as Papa suggested as well as the pink wire from the sniper to the Ignition switch, it sounds like you have spark and the pump is energised but a good place to start. I'm leaning towards Fuel delivery system; If you have an external fuel pressure regulator and gauge I'd check that as well, snipers are finicky on fuel pressure. If you are have the internal sniper fuel pressure regulator those have been known to fail without warning which can either add too much or too little fuel to the system. Did you purchase fuel lately - cobra dude mentioned bad tank of gas or maybe a plugged fuel filter, maybe from crud still in the fuel tank after flushing the system before first hookup to the sniper.
Air, Fuel and spark are the basics and where I start especially if it was running correctly before you shut it off.. That being said there are some really good points above. Good luck none the less.

[Papa]

As John stated, the Sniper's learn table is the only thing that the Sniper self-adjusts. If that got corrupted, it's very easy to simply clear it and start back with the base tune. BPE doesn't, at least when I got mine, provide any tune with the Sniper. You create that initial base tune when going through the setup wizard, which you can re-run at any time. Just save the current ECU stored tune with a name that you'll recognize later if you need to re-install it. I kept a notepad with names and dates and notes of the files I was creating for later reference. Once you get it running smoothly, save that tune so that you can always get back to a known good point if things start going south down the road. I started a thread a couple of years ago on Sniper tuning. I see if I can dig that back up for you.

Found it: https://thefactoryfiveforum.com/show...-Holley-Sniper

[Norm B]

Maybe I missed it but, what distributor and air cleaner are you using? If the above suggestions and BPE don’t solve the problem, try reloading the base program from the hand held and wrapping the distributor with aluminum foil before attempting another start.
That was what the Holley technician had me do when I had an issue remarkably similar to yours. It solved the problem and I made a permanent shield for the distributor. The Sniper is poorly shielded and doesn’t tolerate loose electrons under the hood very well.

HTH
Norm