Engine Running Rich?

[BeePea]

Hello all!

I got my engine to finally start last weekend for the first time, was a great feeling! Couple things I was hoping you could help on (Forte 363 with Sniper EFI)...


I get a strong gas smell from the headers (no side pipes installed yet), is that normal? Doesn't seem like it should be. It's strong enough that you can't stay around it for long before you can't breathe anymore. (car is in a garage, door open)
I don't have my vacuum advance hooked up to anything, I assume I should... Do I route that directly to the sniper?
The idle is pretty rough, maybe related to the above? IAC % got to 10 at 130F, started to see a coolant leak so I stopped it there to fix that.
What temp does the fan turn on? Don't think mine has yet (max temp 130F so far).


I'm sure I'll have more questions as I get them, thanks for the help!

BP

[egchewy79]

I would think you’d want the side pipes on for the EFI to accurately determine AFR. where do you have your O2 sensor currently placed?

[Papa]

I had the same issue when the car was run without side pipes. Also, the Sniper will add fuel when the engine is cool and will gradually reduce the enrichment as the coolant temp comes up.

[Jeff Kleiner]

If your O2 sensor is at the end of the header put the sidepipes on. As Papa Dave said when I had his car with me for body and paint with the pipes off it started running pig rich. When I put all back together it quickly healed itself. Our hypothesis is that the exhaust pulses would pull fresh air back up the end of the header making the sensor report lean and the ECU kept dumping more and more fuel.

Jeff

[BeePea]

Thank you all! I'll put the pipes on this weekend. Makes sense with the O2 sensor location.

What about my vacuum advance, should that be connected? Currently it's just open at the distributor.

[Papa]

Thank you all! I'll put the pipes on this weekend. Makes sense with the O2 sensor location.

What about my vacuum advance, should that be connected? Currently it's just open at the distributor.

I'd connect it. If you don't want to connect it, be sure any unconnected ports on the Sniper are capped. It's not a problem if the pot on the distributor isn't capped.

[BeePea]

I'd connect it. If you don't want to connect it, be sure any unconnected ports on the Sniper are capped. It's not a problem if the pot on the distributor isn't capped.

Thanks, sniper is capped at the moment. I'll just focus on the side pipes and coolant leak.

[hineas]

It looks like your first questions were answered already.

As for the rough idle, that also may be due to the side pipes as well. It could also be due to the IAC not adjusted correctly. I found it was difficult to get the IAC adjusted using the instructions in the manual. It just seemed I was either too high or too low and it was difficult for me to get it dialed in. I found this link on one of the Holley forums and it really helped me get the IAC adjusted.

https://www.efisystempro.com/efi-pro-hangout/holley-sniper-installation-startup-troubleshooting

As for the temp the fan turns on, that is something you can set yourself. The manual says the EFI is pre-set to turn the fan on at 190F. Mine came preset to turn on at 190F and turn off at 180F. You can adjust this on the hand controller in the tuning section under outputs.

[rich grsc]

If your O2 sensor is at the end of the header put the sidepipes on. As Papa Dave said when I had his car with me for body and paint with the pipes off it started running pig rich. When I put all back together it quickly healed itself. Our hypothesis is that the exhaust pulses would pull fresh air back up the end of the header making the sensor report lean and the ECU kept dumping more and more fuel.

Jeff
This is 100% correct. I learned this when setting up my stack EFI