5.3LS won’t rev?

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louu

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Yes. I have it set up on my bench with Tunerpro to do the initial OS setup for my build. You can use universal patcher to do a VATS and Rear 02 delete without even needing to find an XDF or anything for your particular OS.
Awesome, thank you. I'm going to order it right now
 

rusted nuts

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At this point all I’ve got left is drill it out or replace it, the joint had a leak so I bought new studs and the last stud that had threads lost them during disassembly. I need to get this fixed then I can finish out my 2.5” exhaust since apparently dual 2” is too small lol
2" ex. Is plenty big
 

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wuznme

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Have you done everything needed in the ECM for removing all the electronic transmission configuration?
 

iamtherealJayy

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As far as I know everything was removed for the trans, and I have the vss wired in. I took the teuck on a drive today, first time it’s left the house in almost two months. Other than while sitting stopped the idle surges a little bit and it stalled once the truck ran alright.
 

iamtherealJayy

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Oh I had one code, po507 I believe, IAC rpm higher than expected? Or something along those lines.
 

Camar068

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just a quick google search.

check for vacuum leaks with starter fluid around intake/vacuum lines? Spray here and there and if the idle changes....home in on it.
That code could be:
• Vacuum leak
• Leaking air intake after the throttle body
• EGR valve leaking vacuum
• Faulty positive crankcase ventilation (PCV) valve
• Damaged/failed/dirty throttle body
• Failed EVAP system
• Failed IAC (idle air controller) or faulty IAC circuit
 

iamtherealJayy

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I do have one vacuum line that I suspect but it’s one of those special end lines that’s rubbery plasticy garbage. I can wrap electrical tape around it in the morning and replace it tomorrow. It’s too late today and that’s my only option to get to work tomorrow
 

iamtherealJayy

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Does anyone have a tachometer recommendation? I have all working gauges except tach and speedo. I need atleast one of those to work and I figure tachometer will be the easier one. Also with my idle surge, I’ve currently got the throttle cable to fully closed, the idle is really low in my opinion, if I had a tach I’d say probably 400-500, I wonder if I turned it up to around 700? if the idle surge would stop?
 

iamtherealJayy

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350, 350, 350
I’ve put roughly 35 miles on the truck so far and the only two codes I have that returned are cyl4 misfire and iac rpm higher than expected. I replaced the plugs and wires this morning, 1 looked awful, 7 wasn’t even the same as the others, and 2,3,4,5,6,8 looked fine. 8 was a real pita to get out, I went through the fender with an extension to get it. I also put electrical tape over the end of that one hose I suspected could be an issue, I believe it’s the pcv, it runs from the passenger side of the throttle body down to a rail that appears to vanish into the valve cover. The only issues I’m having right now are those two codes, and I melted my speedo cable so that doesn’t work, but I got the vss hooked up(vss adapter pushed speedo cable out around 3” and exhaust touched it) after I get the misfire fixed I need to put mufflers on it. I hate the way it sounds at Lower rpms.
 

iamtherealJayy

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Got all my issues resolved except for two. Still getting a po507 high idle code, and if in neutral and I try to rev it too high it goes to limp mode. I’ve got all gauges finally working besides tach and speedo. Dropping the truck off at muffler shop this week, going with stock manifolds 2.5” dual exhaust to flowtech raptor mufflers with axle dumps for now. Straight pipe is way too obnoxious.
 

iamtherealJayy

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350, 350, 350
Finally decided on a muffler and I’ve got my exhaust clamped together dropping it off Monday to get welded up. Ended up going with manifolds 2.5” pipe and thrush mufflers with 4” tips 90° out the back behind the tires. Fairly quiet at idle little louder when really on it. I noticed when fully warm I’ve got <10psi oil pressure. Always pleasant surprises. Hopefully it’s something simple and not a complete replacement
 

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