Can VATS turn itself back on?
Thread Starter
On The Tree
Joined: Nov 2014
Posts: 102
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From: NW Florida
Can VATS turn itself back on? So I've had the truck running for almost a year, completely trouble free and now it won't start. I got a set of intellitonix gauges and swapped them in a couple weeks ago but the oil pressure wouldn't work so I got the 45 degree 1/8NPT adapter I needed and threw their sensor in and now it starts for about 1/2 a second and dies. Sounds like the VATS but it's been turned off and hasn't given me a lick of trouble since I got it on the road. Is it possible the VATS somehow got turned back on? I can't think of anything that swapping the sensor and plug would have done to make the truck not run. I didn't mess with anything else except pulling the gauges back out to pull the illumination bulbs out of the back of the gauge cluster because I forgot to do that when I swapped in the gauges and I really can't see how that's related.
Truck is a 1991 chevy with an LS3/TR6060 from a 2012 camaro (see build thread in my sig block) and is my daily driver so I need this thing running ASAP, any help is appreciated.
Truck is a 1991 chevy with an LS3/TR6060 from a 2012 camaro (see build thread in my sig block) and is my daily driver so I need this thing running ASAP, any help is appreciated.
On The Tree
Joined: Oct 2017
Posts: 184
Likes: 17
From: napanoch ny
what oil pressure switch did you have originally? the one from the truck with an adapter or the camaro one? i only ask because i believe the truck oil pressure switch is also a fuel pump cut off, where if it doesnt see oil pressure it wont let the motor run or start. otherwise i dont believe vats can turn itself on.
Thread Starter
On The Tree
Joined: Nov 2014
Posts: 102
Likes: 0
From: NW Florida
what oil pressure switch did you have originally? the one from the truck with an adapter or the camaro one? i only ask because i believe the truck oil pressure switch is also a fuel pump cut off, where if it doesnt see oil pressure it wont let the motor run or start. otherwise i dont believe vats can turn itself on.
I did notice that the volts was dropped to around 10 volts while I was trying to start. I put meter on battery and its 12.1 volts, even after throwing it on the charger for a while so I'm going to take that to get load tested, maybe it's just not throwing enough juice to the fuel pump? It is over 4 years old and with the cold we've had here recently maybe it just crapped out. Yes I know cold in Florida
but it's gotten below freezing (I know that's a heat wave for some of you out there) and that's not normal for here so maybe it did it in.Rock
Last edited by rockusaf; Jan 26, 2018 at 02:52 PM. Reason: .
Thread Starter
On The Tree
Joined: Nov 2014
Posts: 102
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From: NW Florida
So battery did have a dead cell so I swapped it out and...same ****. Poked around with the meter and it seems to be getting power to everything like it should and I can hear the fuel pump turn on when I turn the key to on. Not sure why but I decided to unplug the MAF sensor and it ran for 3-4 seconds before sputtering and shutting off, when I plug it back in it just turns over, seems like it wants to start but nothing. I'm really at a loss as to what to look at since that oil pressure sensor isn't going to the PCM or anything so it shouldn't affect the engine at all.
On The Tree
Joined: Oct 2017
Posts: 184
Likes: 17
From: napanoch ny
Did you make the LS motor standalone when you wired it? If you did, just make sure that the fuses are good and that the terminals in the backside of the fuse block are pushed in to the fuses all the way. I had an issue once before where my terminals weren't snapped into the fuse block all the way and when I put a fuse in, it just pushed the terminal down and it wasn't hooked to the fuse.
Thread Starter
On The Tree
Joined: Nov 2014
Posts: 102
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From: NW Florida
Fuel pressure was fine (55 psi with key on and 59-60 psi cranking) and yes the motor is stand alone, it turns out I'm an idiot. In my defense I've been dodging raindrops trying to troubleshoot this since I can't get it in the garage (my woodworking hobby has me building a new bed and it's taking up a substantial amount of real estate in the garage right now). Turns out I somehow popped a fuse and when I was checking it had power but I obviously missed checking the other side of that fuse so power coming in doesn't equal power going out of the fuse is blown so none of the sensors (O2, MAF, etc...) were getting power from the fuseblock powering the motor. 
Anyway, a fuse swap and she fires up and runs like a champ again. I had checked those fuses and would swear I checked both sides of each while my wife had key on, off and trying to start but obviously I missed that F!@#ing one.
I appreciate everyone's help, maybe this will help someone else, always check voltage on both sides of the fuses, especially the ones on a tight fuse block that are tough to see.
Rock
Anyway, a fuse swap and she fires up and runs like a champ again. I had checked those fuses and would swear I checked both sides of each while my wife had key on, off and trying to start but obviously I missed that F!@#ing one.
I appreciate everyone's help, maybe this will help someone else, always check voltage on both sides of the fuses, especially the ones on a tight fuse block that are tough to see.
Rock
