Idle-Up Valve 3.4l

@Speedytech7 no o2 sensor, that's about the only thing I'm missing from the first schematic. Other schematics im getting lost

 

@Speedytech7 maybe that o2 sensor is underneath by that cat, diagram made it look like it was on the headers where that bung plug pic was taken. Everything looks to be good, do I just need to tap in to some other vac lines?

 

This seems to be the routing for the Idle-Up VSV. Looks like it comes from filtered air and then connects to the PCV hose? Hard to tell if it connects to the PCV hose or somewhere else. I don't know what that box thing is on the intake.

Thanks for the help.

 

Yeah the idleup goes from the resonator on the intake tube to the nipple on the front of the intake manifold, but yours is all hooked up wrong and has the wrong nipple, so you'll need some vacuum line and a couple vacuum tees.

 

@Speedytech7 This schematic makes it look like the P/S and the Idle-Up look like they are sharing the line

 

Yeah they both go to filtered air from the tube and then dump into that nipple on the intake manifold (your nipple should have two inputs but doesnt)

Ignore the other stuff that's entirely different, but see my intake manifold has two inputs on that front nipple?

 

@Speedytech7 yeah i see that is a completely different intake than I have. It seems since I don't have a port to install the Idle-Up and P/S. would the Idle-Up effectively be running in its off position?

PS: That turbo is awesome. I bet that thing Juices!!!!!

 

No, if it's missing and nothing is feeding to that nipple then it isn't the cause of your high idle. Probably worth getting the power steering hooked up right though, it should be going to the front nipple too and appears to not be

 

@Speedytech7 The more I thought about it the more it seemed like the vac routing is not the case of the high idle. Thanks for the confirmation. Still on the hunt to fix that high idle though. I'll hook up that power steering line too! Thanks for all the help! Greatly appreciated

 

@Speedytech7 Fuel Trims are -14 at idle and 0 while on the throttle. So the truck is running rich at idle. So vac leak doesn't seem likely. Is it normal to see fuel trims different from idle and throttle?

 

Yeah it isn't uncommon. Is the fuel pressure regulator vacuum line going through the VSV or direct to manifold.

 

@Speedytech7 Fuel Pressure Regulator Vac Line is going directly to the manifold. Should it be on a VSV?

 

yeah 95-97 models use a fuel pressure regulator VSV to determine whether it sees manifold vacuum or atmosphere. Still shouldn't make a huge difference though

 

@Speedytech7 Where would the Electrical Connection be in the loom? The VSV must have been removed by the previous owner.

 

Yeah usually has a red/orange plug hidden behind the manifold in back

 

@Speedytech7 cool I'll give it a gander. Thank you for all the help. I'm so glad this forum exists and has helpful members like you who are willing to help people like me!

 

Absolutely man, glad to help. I have a spare one of those VSVs too somewhere if you need it. I took most of the weird 90s electronics off my truck when I changed to an aftermarket computer.

 

Question. I have a semi-rounded screw at the bottom of my IAC valve from trying to get it off without a JIS screwdriver. I got three screws off but the last one started to strip so I quit the job and put everything back together. I think I might’ve ruined the screw. Where can I get new ones?

Also here is a really helpful video all about the IAC valve. https://youtu.be/agIRNNA-6cs