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Way too rich Sniper

GreatCJ8

Charter Member
Gold Member
City
Lynchburg
State
VA
OK so the Holley tech said, according to the readouts, that it was due to the (new) 02 sensor.
So It's still never run right, out of the box.
I mean it runs but way too rich & severely plugs the sparkplugs. 1 had completely crossed the gap with buildup.
 

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Check to see if it is sucking air. That thing is a thermal vacuum switch. It will have at least one source of manifold vacuum. The other nipples go out to various things, like the EGR valve.

That could be vacuum leak, but I would think you might have a high idle, too, unless the IAC can compensate. At any rate if it is a vacuum leak fix it.
 
Check to see if it is sucking air. That thing is a thermal vacuum switch. It will have at least one source of manifold vacuum. The other nipples go out to various things, like the EGR valve.

That could be vacuum leak, but I would think you might have a high idle, too, unless the IAC can compensate. At any rate if it is a vacuum leak fix it.
I'll see if it's sucking air. I temporarily put a screw in it & tested it, no difference. I can barely make it up hills it's so bad.
I understand why the tech was lead to a faulty 02 sensor, but it's new.
 
I would suggest going through the entire vacuum hose system. I did that when installing the sniper on the Overlander. After fixing my kinked fuel supply line, it has been driving great. Idles around 13.5:1, afr, under load around 13:1, light throttle cruise 14:1. Trims are around +1 to -3. It is still in learning mode, but the trims and adjustments to the table are very small now. Drove it around for 2 hours in varied traffic (heavy street, light street, highway), and it did not skip a beat. Ran like a top. Transmission, not so much. Really need to rebuild one and swap it out.
 
I'll see if it's sucking air. I temporarily put a screw in it & tested it, no difference. I can barely make it up hills it's so bad.
I understand why the tech was lead to a faulty 02 sensor, but it's new.
I would not use a screw, those valves can crack easy, then you must replace the entire valve. Better to get the proper cap for vacuum fittings.


(no idea why the Dorman link shows a bolt, click it and it takes me to assorted vacuum caps)

If the O2 sensor goes, the system will not work. These are wide band O2 sensors, and are more sensitive than regular ones in OEM vehicles. If they get damp, they are ruined. Touch the sensor end, ruined. To prevent condensation, they must be mounted in the top 120 degrees of the exhaust pipe. If mounted level with the ground, or pointed towards the ground, they will fail quickly. Best place on a stock 4.2 is the original O2 port. It allows it to be pointed up and not have condensation collect on the sensor element.

I would trust them, if they think an O2 sensor is the issue, probably correct.
 
Have you monitored the fuel pressure at all when the problem is happening?
No, TBH. Kindof a handful driving it. Needs an alignment too
I did fill it up with fresh gas, $70 bucks ouch. Thank goodness my new job is 3.8 miles away
 
The son has one on his Scrambler, It was very sensative to grounds. He had a ton of issues with teh Holley fuel pump. Also Bad gas. If that ethanol blend sits for a while it really absorbs water.

He did not have much of an issue with Vaccum but I would just brab a good cap at teh parts store. Or cut a new piece of tubing andput the bolt in that. Here in Va you can probably just make a plate and do away with that vaccum plate.


Carl
 
Suggest you post a log and the config file, sounds like there's enough of us with Snipers to maybe spot something off.
 
Check to see if it is sucking air. That thing is a thermal vacuum switch. It will have at least one source of manifold vacuum. The other nipples go out to various things, like the EGR valve.

That could be vacuum leak, but I would think you might have a high idle, too, unless the IAC can compensate. At any rate if it is a vacuum leak fix it.
It is a vent, it is not supposed to be plugged.
 
That could be vacuum leak, but I would think you might have a high idle, too, unless the IAC can compensate. At any rate if it is a vacuum leak fix it.
That's what it is sounding like after an hour on the ph with holley.
Holley says, after I bought a new 02, that it's either fuel pressure or intake leak. Chasing intake leak tomorrow after work. I want to drive it, not chase it!
 
Now you need to save/download and post up the current calibration that goes with that data log.
 
Two of your data logs are just key on with no RPM(no real useable data). The other is just an unsupported log.
 
Two of your data logs are just key on with no RPM(no real useable data). The other is just an unsupported log.
welp, found an online user manual. that's as far as I got tonight. =) Tomorrow's another day. I'll read up on my breaks
 
Two of your data logs are just key on with no RPM(no real useable data). The other is just an unsupported log.
Yep - This is what we see, looks like the log stopped before you went anywhere.




VirtualBox_Win10_26_09_2022_21_06_09.png

The config file and datalog should look something like this
VirtualBox_Win10_26_09_2022_21_16_45.png

Preferably without the dropped out AFR trace though :unsure:



Anyone have an intuitive guide to understanding a sniper kit?

The Holley Sniper forum is a really good place to start.

To get there -
Make a log file
Download the saved configuration from the Sniper to the memory card
Memory card to PC

Save both log and config file locally on PC - they are in different places
Config is probably in something like Sniper EFI/Holley/FW0101/Saved GCF
Datalog is in Sniper EFI/Saved Datalogs

Open the config first - then the datalog

In the config window - Datalog - Activate Overlay - so you can see where in the log the tune is at any rev/MAP pressure

Here's part of a post from the forum

I find the most helpful datalog function, is overlaying the datalog on your Config File.
I'm in the habit of using the datalog Overlay feature every time I review a datalog.
Click on "Datalog" (on the top Toolbar), "Activate Overlay", then "Open Data Log".
You can literally "playback" a recorded event, and watch it as it happened on any screen.
Minimize (shrink) the datalog window, and move it to the bottom of any Config File screen.
Then click & scroll anywhere on the datalog, and watch it playback on your Config File (EFI software).
http://documents.holley.com/techlibr...9r10543rev.pdf (Holley EFI Datalogger Instructions)
https://forums.holley.com/showthread...s-amp-Datalogs (Datalog Information - Read "NOTES")
https://www.youtube.com/watch?v=iqHO...C6FEA0BB99AF17 (How To Record & Email A Datalog)
https://forums.holley.com/showthread...7531#post77531 (Closed Loop Datalog Tuning - Posts #2, #4 & #6)
(Holley Sniper EFI Datalogging Tech Video)

quote_icon.png
Originally Posted by Danny Cabral
 

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Yep - This is what we see, looks like the log stopped before you went anywhere.




View attachment 105567

The config file and datalog should look something like this
View attachment 105569

Preferably without the dropped out AFR trace though :unsure:



Anyone have an intuitive guide to understanding a sniper kit?

The Holley Sniper forum is a really good place to start.

To get there -
Make a log file
Download the saved configuration from the Sniper to the memory card
Memory card to PC

Save both log and config file locally on PC - they are in different places
Config is probably in something like Sniper EFI/Holley/FW0101/Saved GCF
Datalog is in Sniper EFI/Saved Datalogs

Open the config first - then the datalog

In the config window - Datalog - Activate Overlay - so you can see where in the log the tune is at any rev/MAP pressure

Here's part of a post from the forum

I find the most helpful datalog function, is overlaying the datalog on your Config File.
I'm in the habit of using the datalog Overlay feature every time I review a datalog.
Click on "Datalog" (on the top Toolbar), "Activate Overlay", then "Open Data Log".
You can literally "playback" a recorded event, and watch it as it happened on any screen.
Minimize (shrink) the datalog window, and move it to the bottom of any Config File screen.
Then click & scroll anywhere on the datalog, and watch it playback on your Config File (EFI software).
http://documents.holley.com/techlibr...9r10543rev.pdf (Holley EFI Datalogger Instructions)
https://forums.holley.com/showthread...s-amp-Datalogs (Datalog Information - Read "NOTES")
https://www.youtube.com/watch?v=iqHO...C6FEA0BB99AF17 (How To Record & Email A Datalog)
https://forums.holley.com/showthread...7531#post77531 (Closed Loop Datalog Tuning - Posts #2, #4 & #6)
(Holley Sniper EFI Datalogging Tech Video)


quote_icon.png
Originally Posted by Danny Cabral
k, it's running now...
Is it normal, while in closed loop, to occasionally blip to open loop then return to closed loop?
I noticed it doing that occasionally. Here are my logs: attached
 
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k, it's running pretty good now.
Is it normal, while in closed loop, to occasionally blip to open loop then return to closed loop?
I noticed it doing that occasionally. Here are my logs: attached
I would say yes, I think if you turn the self learn feature off it will stop doing that, but not sure. I just let it keep learning and adjusting to current conditions.
 
k, it's running pretty good now.
Is it normal, while in closed loop, to occasionally blip to open loop then return to closed loop?
I noticed it doing that occasionally. Here are my logs: attached
i don't think you attached the logs
Is it normal, while in closed loop, to occasionally blip to open loop then return to closed loop?
There maybe some electrical noise going on,maybe it just needs to learn more?
 
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