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1967 Nova SS
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Discussion Starter · #1 ·
Anybody download the Holley EFI software to Apple Mac? Only option I found on Holley.com was for Microsoft operating platform?
I'm trying to resolve the "rough" engine running with my Sniper. The engine never smooths out, seems like it's surging or stumbling especially with light throttle application. Doesn't matter what speed your running. Doesn't go dead, idles (although rough), starts just not clean or smooth.
 

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Recheck the firing order, check the spark plug wires themselves and the spark plugs. It may not be a Sniper issue.
 

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Recheck the firing order, check the spark plug wires themselves and the spark plugs. It may not be a Sniper issue.
Agree
Always check for firing order, vacuum leaks, no cracks in spark plug wires, etc. I fire it up: get it hot: spray water on headers if running rough to look for dead hole. Could turn off garage light to look for sparks if necessary. Make sure the timing is right. Then I’d chase rfi.
if everything looks right restart the wizard parameters? You can Google sniper trouble shooting algorithm. These things appear pretty simple. I was worried about it but my sniper install worked out so far. Hope yours does too.
 

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These things appear pretty simple. I was worried about it but my sniper install worked out so far. Hope yours does too.

I have a friend that I'm going to try to help on a sniper and it is a RFI problem. We are working on my friends 60 Biscayne also. It has a small RFI problem but we have been working and tried some things today. Haven't had time to get it out and drive to see if we helped it or maybe even fixed it. I've installed or helped on close to ten EFI units now and they are pretty simple until the issues start. Holley knows they have a problem with RFI interference and after speaking with them twice last week I've come to the conclusion that they don't know any more about how to go about finding and fixing the problem than the average Joe out there scratching their heads wondering what's wrong with their new FI unit. You cannot see RFI. There isn't any way that I know of pinpointing just what's causing the interference to the ECU on the throttle body and to be honest you really can't know if you have fixed your problem until it just doesn't happen again. We are going to try to take steps on new installs to see if we can't keep it from being as much of a problem in the future. Many more problems and we will just refuse to install them. A few things that we are doing is we are making sure to go overkill on grounds. We are also trying to isolate the FI wires and sensors as much as possible. Everything is wrapped in some form of loom. When running a ignition box we are trying to keep them as far away from the throttle body as possible.
 

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I put these on and it cut down the RFI . They come in different sizes.
stardrift 10-Pack 9mm Diameter Snap on Ferrite Core Bead Choke Ring Cord RFI EMI Noise Suppressor Filter for HDMI DVI VGA Cable Black (9MM)
 

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I put these on and it cut down the RFI . They come in different sizes.
stardrift 10-Pack 9mm Diameter Snap on Ferrite Core Bead Choke Ring Cord RFI EMI Noise Suppressor Filter for HDMI DVI VGA Cable Black (9MM)
How did you know what sizes to order and would it matter where you installed them on a wire. Could you describe just what wires/sensors you used these on.
 

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Have you looked at any of your data logs or recorded any data logs? One of the greatest thing about the Holley is being able to save data logs of your car.
 

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1967 Nova SS
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Discussion Starter · #10 ·
I started this thread because of my Nova running rough. New Motor, new plugs, new wires, new HEI, new Sniper kit. Going to check plug wire connections and timing again tomorrow. What I have done is take a Data Log on the last trip. Spent all afternoon trying to upload data file and get it in format to add to this post. Would appreciate any and all input as I got a lot to learn in how to read what I got.

Data Log represents about 1 hr 45 min drive. Radio and A/C going strong during the trip account that's how I ride. From start up with top speed about 80 MPH.
Graphs from top to bottom are: AFR, RPM, IGN Timing, TPS.
Not sure how to make much of this information but my primary goal was to see if there was any RFI issues.
The reading for sensors shown are:
Start Up: AFR - 14.7 RPM - 822 Ign Timing - 32 TPS - 12%
Idling after start up: AFR - 13.7 RPM - 706 IT - 18.1 TPS - 0%
Crusin: AFR - 14.3 RPM - 1959 IT - 15 TPS - 8 %
Idling at End of trip: AFR - 14.4 RPM - 673 IT - 17.5 TPS - 1%

So based on what I have read with no overlapping or erratic swings in readings, there doesn't appear to be any RFI issues. Anyone agree or disagree?



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Discussion Starter · #11 ·
Got to thinking after I made the last post that the RPM numbers don't really mean anything. Timing is not controlled with the Sniper. Ignition is straight HEI.
 

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Discussion Starter · #13 ·
Well I don't know what I don't know. In post #11 I meant to say Ignition Timing not RPM. I will agree that timing is important, just don't understand I guess how the Sniper is reading the timing level.

Relative to RFI. Do you think that is not a problem based on the graph or is there another sensor reading I need to look at. My "tech" knowledge is ZERO.
 

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I have absolutely no knowledge of the Sniper system. I know there are many here who do know a ton! There's also the Holley Sniper Forum you could peruse:


Maybe someone there will know the answer to your query and get you the info you need.

Best of luck, hoping it's an easy fix! I do know any time you have any voltage anywhere near any of the EFI wiring or CPU. it wreaks havoc on the system. Even the wiring to the handheld (near the antenna or other powered lies under dash?) can cause tuning issues from what I've seen and heard here and elsewhere.
 

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1963 Nova w/ Pontiac OHC6
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Well I don't know what I don't know. In post #11 I meant to say Ignition Timing not RPM. I will agree that timing is important, just don't understand I guess how the Sniper is reading the timing level.

Relative to RFI. Do you think that is not a problem based on the graph or is there another sensor reading I need to look at. My "tech" knowledge is ZERO.
The Sniper is not reading your timing at all. Those numbers are for the canned program that comes with the Wizard tune and will be displayed on the handheld and in the datalogs but mean nothing. If you are not using the Sniper to control timing, you need to disable timing control in the System ICF. Go to the Idle ICF, then IAC Settings and turn off Idle Spark. Then go to the System ICF, Basic I/O and turn off the fan and A/C controls if you're not using them. The less things the Sniper has to think about, the better (as long as you're not using those functions). When you do a datalog, do yourself a favor and run a MUCH shorter log. It is really hard to see what's going on with a datalog that long. Log specific examples of problem areas as well as a couple of known good areas. It will be a lot easier to compare data when you're not looking at an hour and a half worth. As for posting your logs here, I would try to put both the datalog and the Config file into a .zip format and upload that. Just don't forget to download the tune file from the Sniper first so that whoever is looking at your config file can see what's going on with the Learn Table. Also, always make sure that you post both the datalog and config file together. Without the config all anyone can really do is guess.
 

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Discussion Starter · #16 ·
63 bomb - Thanks for the feedback. Got a lot to learn about this EFI stuff.
I didn't think the timing numbers meant anything with the timing not being controlled by the Sniper.
I got a Holley tech guy on the phone and he was most helpful. With his help and looking at "smaller" data segments I feel good about not having RFI issues. No skips, no huge swings, no movement right to left in data segments for multiple sensor reading.

I'm going to look at spark plug wires (although their new), voltage and whatever else I can think of. I'm beginning to think it's not a Sniper issue.
 

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63 bomb - Thanks for the feedback. Got a lot to learn about this EFI stuff.
I didn't think the timing numbers meant anything with the timing not being controlled by the Sniper.
I got a Holley tech guy on the phone and he was most helpful. With his help and looking at "smaller" data segments I feel good about not having RFI issues. No skips, no huge swings, no movement right to left in data segments for multiple sensor reading.

I'm going to look at spark plug wires (although their new), voltage and whatever else I can think of. I'm beginning to think it's not a Sniper issue.
The 60 Biscayne we had at the show had a brand new bad sparkplug wire. Although we made up one of the ends the other was already made up out of the box. By just pure dumb luck I found it. It did run better afterwards but with the weather he hasn't really got to get it out and drive. We have some of the RFI noise filters ordered for the truck. Hoping they help.
 

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63 bomb - Thanks for the feedback. Got a lot to learn about this EFI stuff.
I didn't think the timing numbers meant anything with the timing not being controlled by the Sniper.
I got a Holley tech guy on the phone and he was most helpful. With his help and looking at "smaller" data segments I feel good about not having RFI issues. No skips, no huge swings, no movement right to left in data segments for multiple sensor reading.

I'm going to look at spark plug wires (although their new), voltage and whatever else I can think of. I'm beginning to think it's not a Sniper issue.
What engine is this mounted on? Is it a fresh rebuild or an older build? There are a lot of things that can make it run rough that revolve around the tune file in the Sniper, but there are just as many that can cause the same revolving around the engine itself. The biggest thing to remember about aftermarket EFI is that there is no "direct link" to the engine. With a carb, the engine tells the carb what it wants and the carb responds. With EFI, it will do exactly what it's programmed to do... even if it's wrong for the engine. I've learned a lot about these units in the year I've had one on my car but am still by no means an expert. That being said, I'd be happy to take a look at your files if you can post them up here.
 

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Discussion Starter · #20 ·
Engine is new 350 Pace Performance crate. Rated 390 [email protected] 5800, 420 Torque @ 4000.

Right now I can't figure out how to attach the data log. I'll have to do some research. Tried attaching, copy/paste. No luck.

I do appreciate your willingness to look at the file.
 
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