LS1 intake installed engine runs but.. Tuning?
LS1 intake installed engine runs but.. Tuning? LS1 intake, LS6 injectors, Stock valley cover with opsu mod, stock airbox with super crap angle going into the throttle body. I'm using a 1/2 tb adapter.
Engine fired right up and was kind of pissed of for a few mins. No vacuum leaks. Only problem is that my engine doesnt want to rev. I can barely get it to hit 5k and it takes forever. Is this a tuning issue? Feels like its in 4 cylinder mode which its not cause I removed the PB vacuum sensor and the DOD connector. I think that my intake elbow is throwing the Maf way off due to its extrem angle. Any tunners wanna chime in? I was thinking that my car would still be driveable. Not!
Engine fired right up and was kind of pissed of for a few mins. No vacuum leaks. Only problem is that my engine doesnt want to rev. I can barely get it to hit 5k and it takes forever. Is this a tuning issue? Feels like its in 4 cylinder mode which its not cause I removed the PB vacuum sensor and the DOD connector. I think that my intake elbow is throwing the Maf way off due to its extrem angle. Any tunners wanna chime in? I was thinking that my car would still be driveable. Not!
Thanks JDMC5
I'm stuck in 4 Banger mode. I unplugged the dod connector so I am throwing 3401,3425,3441,3449 code. I guess the computer limps into 4 cylinder mode. No fuel or spark. I've got a tuner coming over once I get my air intake ducting squared away. Its way worse then nate's car was, due to my thick *** adapter. My tuner wants to redo the map tables or something like that. He needs the car for s few days.
I'm stuck in 4 Banger mode. I unplugged the dod connector so I am throwing 3401,3425,3441,3449 code. I guess the computer limps into 4 cylinder mode. No fuel or spark. I've got a tuner coming over once I get my air intake ducting squared away. Its way worse then nate's car was, due to my thick *** adapter. My tuner wants to redo the map tables or something like that. He needs the car for s few days.
TECH Regular
Joined: Nov 2009
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From: Farmington Hills, MI
When I swapped intake manifolds I didn't change injectors. I only changed them after the cam, and that brought a whole world of hurt because our ECMs apparently handle fuel pressure and flow rate calculations a bit different than the other DOD/AFM and non-DOD/AFM cars. The change in the elbow and thick adapter are hurting your tune without a doubt, but that is compounded by the injectors. They flow about the same as ours, but all of the offsets and adders are different because they are physically different. Generally, the best practice is considered to be using some known good fuel injector data (say from an LS6 Vette) and tuning MAF and VE to get the commanded AFR.
On The Tree
Joined: Dec 2010
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Thanks JDMC5
I'm stuck in 4 Banger mode. I unplugged the dod connector so I am throwing 3401,3425,3441,3449 code. I guess the computer limps into 4 cylinder mode. No fuel or spark. I've got a tuner coming over once I get my air intake ducting squared away. Its way worse then nate's car was, due to my thick *** adapter. My tuner wants to redo the map tables or something like that. He needs the car for s few days.
I'm stuck in 4 Banger mode. I unplugged the dod connector so I am throwing 3401,3425,3441,3449 code. I guess the computer limps into 4 cylinder mode. No fuel or spark. I've got a tuner coming over once I get my air intake ducting squared away. Its way worse then nate's car was, due to my thick *** adapter. My tuner wants to redo the map tables or something like that. He needs the car for s few days.
Yea I tried to do the same thing when I put my LS6 intake on. You have to have the DOD connector properly wired and connected with a stock tune otherwise it is automatically in V-4 mode.
I started mine with the DOD connector not connected and immediately could tell it wasn't right.
TECH Enthusiast
Joined: Nov 2008
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You have to physically turn the DOD off in the tune/computer, then it will run on 8 always.... and you dont have to disconnect anything. You need oil pressure sensor it is used for more than oil press and DOD, and you need the booster vac sensor same goes for it.
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Verdad Gallardo TECH Enthusiast
Joined: Nov 2008
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off the top of my head ... when to activate V7mode, activete/deactivate V4 mode, limp mode ,abuse mode, oil life system (Oil pressure/specific gravity)conjunction. I would have to look up more, sometimers is present!
Yea I tried to do the same thing when I put my LS6 intake on. You have to have the DOD connector properly wired and connected with a stock tune otherwise it is automatically in V-4 mode.
I started mine with the DOD connector not connected and immediately could tell it wasn't right.
I started mine with the DOD connector not connected and immediately could tell it wasn't right.
On The Tree
Joined: Dec 2010
Posts: 109
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Yes, if you don't have a catch can, get one now! It's unreal how much oil mist will enter back into the engine!
As far as a vacuum source I used the factory ls6 intake nipple for the pcv, and drilled and tapped my TB adapter for the brake booster vacuum source.
If you don't have a thick enough adapter plate to do that, then look at a 4-6-8 cylinder fox body mustang vacuum block. You can run the ls6 intake vacuum source to that vacuum block and tee both the brake booster and pcv to that.
As far as a vacuum source I used the factory ls6 intake nipple for the pcv, and drilled and tapped my TB adapter for the brake booster vacuum source.
If you don't have a thick enough adapter plate to do that, then look at a 4-6-8 cylinder fox body mustang vacuum block. You can run the ls6 intake vacuum source to that vacuum block and tee both the brake booster and pcv to that.
So are you running the LS6 PCV valve into a catch can from the intake nipple?
I've got my PB hose going from the intake to booster (I drilled out the stock nipple and tapped the hole and installed a 11/32 fitting) and my PCV going from my tapped tb adapter to the rear valve cover without a valve cause I do not know what to do/use
Nice install BTW! I thought about putting my MAP sensor up front too. I put it in the rear where I can't get to it without pulling the intake
On The Tree
Joined: Dec 2010
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Thanks for the pic, and I will get a catch can. I am well aware of the oil coated intake manifold that I have pulled off 3 times now LOL.
So are you running the LS6 PCV valve into a catch can from the intake nipple?
I've got my PB hose going from the intake to booster (I drilled out the stock nipple and tapped the hole and installed a 11/32 fitting) and my PCV going from my tapped tb adapter to the rear valve cover without a valve cause I do not know what to do/use
Nice install BTW! I thought about putting my MAP sensor up front too. I put it in the rear where I can't get to it without pulling the intake
So are you running the LS6 PCV valve into a catch can from the intake nipple?
I've got my PB hose going from the intake to booster (I drilled out the stock nipple and tapped the hole and installed a 11/32 fitting) and my PCV going from my tapped tb adapter to the rear valve cover without a valve cause I do not know what to do/use
Nice install BTW! I thought about putting my MAP sensor up front too. I put it in the rear where I can't get to it without pulling the intake
Yea, I wanted the MAP where I can see and get to it
On The Tree
Joined: Dec 2010
Posts: 109
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Check it out. Just for me and you I destroyed my stock ls4 intake because I don't like the idea of not having a pcv valve if I had one before...
Look at the pictures. That nipple on top of the intake is just that, there is no actual valve, so you and I can rest easy now....
This is good news. From What I've read, its in the intake. Funny pics man. Just what were you going to you with it? LOL. Destroyed the crap out of that manifold.
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David gxp, maybe I dont get it... you keep saying the LS4 pcv is in the intake?
The LS4 has an integerated PCV system built into the front end of the rear valve cover, it is a non serviceable unit. The vacum source is from the LS4 intake manifold.
I have diagrams of the vacum connection at a fitting just behind the throttle body and also another application showing it at the nipple atop the LS4 intake.
Also some of these engines came with a vented oil filler cap and others did not have the vented cap, the vented one is directional.. outside air in.
hope this helps...
The LS4 has an integerated PCV system built into the front end of the rear valve cover, it is a non serviceable unit. The vacum source is from the LS4 intake manifold.
I have diagrams of the vacum connection at a fitting just behind the throttle body and also another application showing it at the nipple atop the LS4 intake.
Also some of these engines came with a vented oil filler cap and others did not have the vented cap, the vented one is directional.. outside air in.
hope this helps...
Last edited by Ill_Born_ss; Jan 20, 2011 at 06:58 PM.