#81  
Old 05-22-2022, 09:53 AM
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I would at least attempt cleaning it. And post up a log, and I'd bet FJ would take a look and compare with the 2 units he has in operation to see how far off you are. That definitely looks like the engine has been fat at some point. It could've been due to the injector issue you had initially, or it could be still, or both.

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  #82  
Old 05-22-2022, 09:56 AM
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Quote:
Originally Posted by Scott65 View Post
FJ, do you know if there's a free version of Holley software that allows looking at datalogs? I'd like to check it out, and be able to help others. If the OP were to post a log, you could probably tell between the 2 you use if his idle pulsewidth is in the ballpark huh?
You can download it to your PC from here.

https://www.holley.com/support/fuel_...ion/sniper_efi

I think all you need is software V1 . 1.3

Yep it's starting to sound like a datalog is going to be the best way to diagnose what's going on. Yes it will show injector pulse width and help narrow down the problem.

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  #83  
Old 05-22-2022, 10:01 AM
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Cool thanks. I have no data from a Holley to compare to at least currently. But since you have 2 well tuned versions, you'd probably be able to spot a far off situation in the OP'S.

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  #84  
Old 05-22-2022, 10:11 AM
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What software are you currently using Scott? I thought it was Holley based?

I've never seen or used FiTech and pretty sure you aren't using that, but I know JLmounce has a lot of experience in that. Between all of us I think we can get it figured out.

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Old 05-22-2022, 10:21 AM
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I use Megalogwiewer, which is what is used for Megasquirt, and I think BigStuff3, which is about obsolete now I think. That link had the dreaded 404 error... Their page is not easy for me to navigate, but perhaps I'll stumble on it eventually. For now I'll leave Holley to those who have it available...
ETA: I think maybe I now have it. It was a later version I think... we'll see when someone posts a log I guess.

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Last edited by Scott65; 05-22-2022 at 10:37 AM. Reason: Addition
  #86  
Old 05-22-2022, 12:59 PM
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What do the plugs look like? The o2 will almost always have soot on it to an extent. However the fact that your o2 is covered on one side heavily does indicate a rich run situation.

Having a lean reading at the computer with an actual rich condition at the engine screams exhaust leak before or near the oxygen sensor.

You should have a minimum of 18” of pipe after the sensor before the pipe exits to atmosphere. Another thing that tends to trip people up is using the clamp on o2 bung supplied with the unit. It’s radius is made for a 2.5” pipe. If you are clamping it to a 3” or 3.5” header collector, it will almost never seal.

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  #87  
Old 05-22-2022, 03:04 PM
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I tried to do a data log but nothing saved from my attempt. There were 5 data logs on the sd card from the previous owner. I will pull the plugs after it cools down. I am running Exhaust manifolds and a pypes 2.5 inch exhaust with a x pipe.

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Old 05-22-2022, 03:05 PM
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M<aybe someone can call me? 708-204-7341 Thanks John

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  #89  
Old 05-22-2022, 03:06 PM
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FJ I couldnt download the software from the link you posted there was a 404 error.

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Old 05-22-2022, 03:25 PM
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I have 28" from the o2 sensor to the x pipe.
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  #91  
Old 05-22-2022, 04:00 PM
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I found it under technical resources, Sniper. Whether it's right or not Im not certain.
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  #92  
Old 05-22-2022, 05:25 PM
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I think I'll change the plugs 1st.
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  #93  
Old 05-23-2022, 06:27 PM
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All 8 look the same.
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  #94  
Old 05-23-2022, 08:28 PM
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Do you have a way independent of the Sniper to check fuel pressure? Something is not as the ecu expects. If you've ruled out vacuum leaks, and exhaust leaks ahead of/ immediately after the O2 sensor, either something in the prompts that determine the baseline is wrong, or the fuel pressure is higher than the ecu thinks it is. This also assumes the ignition system is healthy.

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  #95  
Old 05-23-2022, 11:45 PM
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We really need a log. I’d want to see what your fuel trim and fuel learn is doing.

There’s a disconnect between what the ecu thinks is happening and what is actually happening.

I’d also like to know what size line your return line is. One easy way to increase fuel pressure artificially is to use an undersized return line.

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  #96  
Old 05-24-2022, 05:58 AM
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The gauge on the fuel line going to the throttle body said 70 psi. The line kit I bought from holley and both sides are 3/8.

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  #97  
Old 05-24-2022, 06:01 AM
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Picture.
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  #98  
Old 05-24-2022, 06:30 AM
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Is base pressure 58psi on this system?

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  #99  
Old 05-24-2022, 10:09 AM
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Is that standard 3/8" fuel hose on the car, or is that pushlock style efi hose that you added a clamp to?

70 psi is too much fuel pressure, you should be running around 58 psi, unless the regulator is being vacuum referenced in which case it should be more like 43 psi at idle.

Start looking for an obstruction in your return line or how the fuel enters the tank. Is it possible you have your feed and return lines backwards at the fuel hat?

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  #100  
Old 05-24-2022, 10:10 AM
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Yes base pressure on the Holley should be 58 psi.

3/8 for a return line could be on the small side, depending on the size pump you are running. 3/8 would probably work up to about a 255 LPH pump, anything bigger than that I'd want to see 1/2", but I always run 1/2" anyway regardless just in case of a future pump upgrade, I don't want to have to go back and revisit it. But of course I run full length returns on my stuff. If it's a kit from Holley I would assume it's a very short return back at the fuel tank somewhere....

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Last edited by Formulajones; 05-24-2022 at 10:18 AM.
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