brettzo007
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Those have been checked thoroughly and tightened. There is no play/rattle.What about the bolts on the header collectors? I heard others with this problem.
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Those have been checked thoroughly and tightened. There is no play/rattle.What about the bolts on the header collectors? I heard others with this problem.
If the fuel system/pumps was bad for any reason, you'd see that in the logs too. Can't wait to put my return system in when I get time and fire up my PBD tune.If my knock is indeed false, it only appears when the return fuel system is running fuel. It's still in the car outside of the pump and the return line off the fuel rail. What about those is going to cause knock if not the tune? Again, it's either tune, bad 350 pumps from Sai (that start and idle the car just fine independently) or FPR. Literally only options.
UPDATE: I re-flashed back to stock and then the most recent Lund revision today and knock for the most part is gone and timing is being added in most instances. The car feels significantly better today after the changes noted earlier in the thread completed a couple of days ago. I just drove for over an hour and night and day difference. The car actually pulls now, hard, compared to a slug yesterday with 9.99* being pulled on almost all WOT pulls.
Changes that helped to rectify:
-Remove AC bracket mount bolt (there were signs of contact with headers). Instead of trimming the bolt, I removed it and zip tied to completely rule out the possibility of it making contact again in future.
-Removed header high flow cats. When pounding one of the cats with my hand while under the car, there was a strong rattle noise present. When removing the cat and inspecting inside the piping, the cat was loose and moving around slightly. It was failing and I'm glad it's now off, especially with boost.
-Tighten all exhaust connections, trans mounts, inspected motor mounts - all were good.
-Flash back to stock/re-flash Lund tune to car.
For now my issue is gone and as several others have been experiencing this, I thought I would share. The AC bracket bolt and rattling cat is what I suspect were the culprits. After fixing all of this and re-flashing the tune, things seem to have completely resolved after completing the above changes.
Hoping this helps others...I will be monitoring/logging the car closely to ensure it's gone for good, but man do I feel good at the moment after several weeks of troubleshooting this. Knock sensors have not been desensitized and the same tune that was previously showing 4 to 9.99* retardation is now running much better.
2 logs from today below. Night and day difference from a knock perspective performance/feel of the seat. No more hesitation when accelerating, aside from a couple of blips here and there when changing gears, but then goes back to adding timing. This is the exact same fuel and tune that I had logged in my previous post, only difference being a re-flash after the changes made.
Log 1: Idle and WOT
https://www.dropbox.com/s/rhcr0pa27jpittk/datalog1%20sept%209%20idle%20wot.csv?dl=0
Log 2: Idle, WOT and a bit of cruise
https://www.dropbox.com/s/qivpogqurwfpsos/datalog1 sept 9 wot and cruise.csv?dl=0
Its a really good way to get a rough idea on HP.In watching this video, does anyone know whether multiplying MAF flow rate x 10 as explained at 7:06 would provide a pretty good flywheel HP estimation?
The "gap" is normal, that has about .000001% effect on boost.Before the install I had looked inside the valve and did notice some gap around the flap and wondered how it wouldn't leak. Race bypass valve a good option? Have read mixed reviews on the new version.
Thanks. Then I have more digging to do.The "gap" is normal, that has about .000001% effect on boost.
Don't worry about that, its designed like that.
As long as your valve opens and closes, you are GOLDEN
No, otherwise I would be making 860 hp on my 93 tune that dyno'd at 660. The max Maf lbm per minute the MAF can read is capped at 86.68. I reach peak reading at ~6500... If his calculation was correct and I followed the line up to my shift point I would have >1000 at the flywheel on e85 and 93.In watching this video, does anyone know whether multiplying MAF flow rate x 10 as explained at 7:06 would provide a pretty good flywheel HP estimation?
[ame]