Emissions Help Needed! (1 Viewer)

[NocalFJ60]

You sure a fuse wasn't pulled out when it was desmogged? Double check all your fuses. Measure voltage across them with the truck running. They should all be zero. The emission board provides a ground from what I remember. Unplug each VSV and measure the plug coming to it with your meter. How did you measure 12V last time? Did you measure with your meter across both pins? If the board is not closing the ground path then you will get nothing. Try measuring each pin separately with your other lead on a good ground point in the engine bay. You should measure 12V on one of the pins for all the connectors that supply power to the VSV's. If you don't then you got a power problem with a bad fuse or wiring.

Next check your ground on pin 7 on the board with it connected. One lead on pin 7 and the other on a good ground inside the cab should show ~.6 ohms.

I agree it is a lot of time but I can talk you through this you don't need to take at some where yet unless you are just done with it.

 

[toyodafj40]

There is a vacuum sensing valve located on the left side inner fender well it has 1 vacuum hose and 1 single wire that plugs into it which grounds the signal wire from the computer,use a test light on it and slowly rev the engine up and see if the signal becomes grounded .make sure there is vacuum to it and it's properly routed.

 

[LAMBCRUSHER]

bump in new conductors from comp to VSVs: crimp a pair of alligator clips to the ends of each wire, carefully strip a piece of insulation from the the end of the factory wire that solders to the comps ground to the VSVs clip one end of new wire w/ clip to the stripped conductor piece of the comps connection point and the other(wrapped around a pillar and into fender well outside vehicle) to the ground wire connection at the VSVs. This is a temporary wire, use it to see if the comp operates the VSVs. If it does with temp wire on, then you have an open conductor in the harness from comp to switches.....

 

[AdamKFarmer]

You sure a fuse wasn't pulled out when it was desmogged? Double check all your fuses. Measure voltage across them with the truck running. They should all be zero. The emission board provides a ground from what I remember. Unplug each VSV and measure the plug coming to it with your meter. How did you measure 12V last time? Did you measure with your meter across both pins? If the board is not closing the ground path then you will get nothing. Try measuring each pin separately with your other lead on a good ground point in the engine bay. You should measure 12V on one of the pins for all the connectors that supply power to the VSV's. If you don't then you got a power problem with a bad fuse or wiring.

Next check your ground on pin 7 on the board with it connected. One lead on pin 7 and the other on a good ground inside the cab should show ~.6 ohms.

I agree it is a lot of time but I can talk you through this you don't need to take at some where yet unless you are just done with it.

I haven't checked all the fuses, I didn't think there was one that controlled the E board. I just measured each plug with a good ground, the + side always had 12V. I checked the ground with the side of the truck, but only continuity. Ill check resistance. I'm taking it in for a few things but if we can figure it out itll save me a few bucks! Im all for that!

 

[AdamKFarmer]

Norcal- Maybe you can school me on some fuses. Why would the voltage be 0 while the truck is on? I'm confused!

 

[NocalFJ60]

Norcal- Maybe you can school me on some fuses. Why would the voltage be 0 while the truck is on? I'm confused!

If the fuse is bad or open, then you will measure 12V across the fuse. If they are all good, the you should not measure any noticeable voltage across the fuses. This is done with the truck on so be careful where you put the leads. You can also pull fuses and measure continuity.

So the VSV's are not getting a ground? You can confirm this by measuring no continuity from the ground lead on the VSV supply connector to ground with the engine on. This means the board is not grounding the VSVs to actuate them.

 

[NocalFJ60]

You find the problem?

 

[AdamKFarmer]

You find the problem?

Not yet, the shop is still working on it, I will post up the answer as soon as I find out!

 

[AdamKFarmer]

Okay. Answer found! I got it back from the shop running like a top. The entire problem? The PO hooked the seatbelt sensor into the cat thermo sensor and the thermo sensor in the seatbelt. This was causing the entire problem. I didn't even think to check that!