I will try to video with the timing light, should be ~12*, we verified at the beginning of this journey.
Holley Sniper 2GC to 2F Install using Mosley Motors adapter
- Thread starter KY Longhunter
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Hey John, @desmocruiser
I must have called Holley tech line at least 8 times in the course of 3 weeks. It is a real pain in the ass as you are on hold as many as 35 minutes when you call mid-day. I’d put the phone on speaker in the garage and go about doing stuff u til the countdown clock said there was 1 caller ahead of me. Most of the time I came away from the phone call feeling smarter but still getting the same results. If you decide to go this route with a call….do it a few minutes after they open or a few minutes before they close
I don’t know that you’ve asked them anything but may be worth a try just to gain another insight or rabbit-hole to go down. I will say you’ve got me inspired to try again to set my system up. EVEN THOUGH it is damn near perfect as is…what causes that in people?
I must have called Holley tech line at least 8 times in the course of 3 weeks. It is a real pain in the ass as you are on hold as many as 35 minutes when you call mid-day. I’d put the phone on speaker in the garage and go about doing stuff u til the countdown clock said there was 1 caller ahead of me. Most of the time I came away from the phone call feeling smarter but still getting the same results. If you decide to go this route with a call….do it a few minutes after they open or a few minutes before they close
I don’t know that you’ve asked them anything but may be worth a try just to gain another insight or rabbit-hole to go down. I will say you’ve got me inspired to try again to set my system up. EVEN THOUGH it is damn near perfect as is…what causes that in people?
Hold off on panicking or calling Holley! We’ve taken a week to to do a 20-30 min process.
We keep stopping right before we have the chance to see it work or not work and then have to start all over from scratch each time because we throw in the towel
It’s time to lock in and focus and be a dickhead about details mattering
It seems close now. The IAC is tracking with warmup conditions. There is more data to support it working properly than there being a problem. The throttle blade is a hair closed too much. Needs a little more air. It IS finicky. You can do it.
1) Adjust it hot now, see how close you can get it and then drive it. Check and adjust again. Drive it. See if the IAC stabilizes. See if it drives ok.
2) show the timing in a video
3) This will reveal something
We keep stopping right before we have the chance to see it work or not work and then have to start all over from scratch each time because we throw in the towel
It’s time to lock in and focus and be a dickhead about details mattering
It seems close now. The IAC is tracking with warmup conditions. There is more data to support it working properly than there being a problem. The throttle blade is a hair closed too much. Needs a little more air. It IS finicky. You can do it.
1) Adjust it hot now, see how close you can get it and then drive it. Check and adjust again. Drive it. See if the IAC stabilizes. See if it drives ok.
2) show the timing in a video
3) This will reveal something
This is a totally valid and normal experience
We can take the magic out of it and as long as we know how to make it close to perfect, we can choose what level of perfection is acceptable.
We can take the magic out of it and as long as we know how to make it close to perfect, we can choose what level of perfection is acceptable.
I had a few successful short drives last evening, I plan to get back out today for a longer up to temperature drive and check again after full warm up!
I will upload a couple of videos of the processes and keep everyone posted, thanks again for all the support, technical advice and mechanical therapy!
Here is the latest:
A few drives this weekend and all seems good!
Restart this morning after not driving since Saturday and it had a moment of odd running, but recovered.
After it recovered all seemed well and I was able to put a few miles on the truck so that I could make a fine tune adjustment (IAC 2% to ~6%) and get a timing video. However, before I could get home it acts up and I have to pull over.
Odd occurrence after drive 2 - https://youtube.com/shorts/xfTjrosQp5w?si=sCEK_BpToLrOVhx-
I let the truck sit for a few minutes and it restarts without issue an all seems well and get gas, drive home all is good.
I adjust the IAC up slightly as planned.
Increase IAC 2-6 - https://youtube.com/shorts/uwjHqbLYdsU?si=pWjeFeezMK6vIeOs
Take a drive all seems good, grab a video of the timing.
Timing - https://youtube.com/shorts/gXf0Y1FlLu8?si=q0ThicTrIjzDBWhM
A few drives this weekend and all seems good!
Restart this morning after not driving since Saturday and it had a moment of odd running, but recovered.
After it recovered all seemed well and I was able to put a few miles on the truck so that I could make a fine tune adjustment (IAC 2% to ~6%) and get a timing video. However, before I could get home it acts up and I have to pull over.
Odd occurrence after drive 2 - https://youtube.com/shorts/xfTjrosQp5w?si=sCEK_BpToLrOVhx-
I let the truck sit for a few minutes and it restarts without issue an all seems well and get gas, drive home all is good.
I adjust the IAC up slightly as planned.
Increase IAC 2-6 - https://youtube.com/shorts/uwjHqbLYdsU?si=pWjeFeezMK6vIeOs
Take a drive all seems good, grab a video of the timing.
Timing - https://youtube.com/shorts/gXf0Y1FlLu8?si=q0ThicTrIjzDBWhM
Grab a snack, decide to take another drive with no further adjustments and it goes back into crazy mode!
So I am as perplexed as ever why it occasionally jumps into this mode?
So I am as perplexed as ever why it occasionally jumps into this mode?
I had something on Saturday I know has not happened before. My hand held display is always the same series of numbers, same duty cycle, same air..etc
Saturday I start it and run about a mile. As I am looking to watch the magical temperature rise to over 160. I noticed the IAC was all over between 30 -100 and the duty cycle was bouncing around as well. mAF/s was also wonky…. It was as if it was interfered with by a strong electrical field disturbance…yet, the truck ran as perfectly as always.
I pulled off the road, shut it down and restarted….normal reading.
No idea it was the first time ever in the last 2 years and I am questioning whether or not you are getting some erroneous data display and the truck has a hiccup somewhere electrically….. JUST THROWING THE DICE at this point for you.
Saturday I start it and run about a mile. As I am looking to watch the magical temperature rise to over 160. I noticed the IAC was all over between 30 -100 and the duty cycle was bouncing around as well. mAF/s was also wonky…. It was as if it was interfered with by a strong electrical field disturbance…yet, the truck ran as perfectly as always.
I pulled off the road, shut it down and restarted….normal reading.
No idea it was the first time ever in the last 2 years and I am questioning whether or not you are getting some erroneous data display and the truck has a hiccup somewhere electrically….. JUST THROWING THE DICE at this point for you.
Might want to take 20 minutes and make sure that the fuel injector clips haven't broken or came off. It appears from the screen that you're going lean. (AFR in the 20's and 30's) Classic symptom of the fuel injector not being secured. If that's not it, you've lost virtually nothing. It's a "thing." It's happened to me with similar symptoms. I chased my tail for a week trying to figure it out. This is what mine looked like when I got in there. If you do this, just go ahead and run a small zip tie around both of them now. This will give you some peace of mind in the future.
Thank you! I will check that out,
After reading more about this issue I was optimistic it could be the smoking gun I have been in search of.
I was disappointed to find they all looked snug and intact, I zip tied them none the less since it is a known issue.
I was disappointed to find they all looked snug and intact, I zip tied them none the less since it is a known issue.
Of course with this issue, it starts and runs perfectly after reassembly!
Until doesn’t and goes back into a running poorly with erratic readings.
I'd start from scratch- test coil, load test battery, test alternator, test compression, timing, plug wires to correct cylinder, dist cap/rotor in good shape, valves, head bolts,vacuum leaks, fuel pressure, wiring hygiene.......
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One more thing I would suggest. Look down the throat while it's running and make sure that both injectors appear to be firing evenly. It should be apparent. Especially try to do this while it's running rough and going lean. Each time you do something significant, (like making sure the injectors are 100 percent secure) start over with a new configuration. Act like you just pulled it out of the box. Although a lot of your videos show it not up to operating temp, it has still learned some bad habits from trying to keep it running during the troubleshooting process. Those bad habits bleed over and will make it not run correctly even if you've corrected the problem. Also, stick with it. You'll get it. And it can/will be rewarding. I had a lot of problems in the first year. It was a completely new platform that I had no experience with. I basically daily drive mine and haven't touched a thing in almost 3 years after finding the "sweet spot."
It is certainly becoming more perplexing,
This morning I rechecked the wiring and vacuum leaks, changed out the IAC valve for the original one and dialed it back in to range (I had replaced it back last Summer during the initial diag) reran the wizard, all with the exact same result.
What does recheck entail?
I have just gone back over the wiring and connections, confirming they tight and clean, for vacuum, I use carb cleaner. A couple of times I was able to do the checking process while it was running poorly to see if I could get anything to change, no luck so far.
Whats your voltage look like on a multimeter?
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