Bill,
The following post is cut-and-pasted from my other home, the 3FE list at Yahoo Groups. It's rather long, but it addresses your issue pretty much exactly.
BTW, John Hocker is the 3FE list's version of C-Dan.
Good luck,
Curtis
91FJ80, 234K
Hocker sent me the 3 VSV's Vacuum Supply Valves for a FJ80 as the ones for the FJ62 are discontinued. My Air Injection VSV was shot for sure according to the tests in the FSM.
Just that one is available but its $67 whereas the whole mount with all 3 is $105 from the esteemed Senior Hocker.
Here is the difference, the FJ62 VSV's mount horizontally and have perminent wiring on two of them. The FJ80 ones mount vertically and all can be unplugged.
I used the mount rail from the FJ62 and just swapped the new VSV's to it, they unscrew easily.
Another difference is that in the diagrams the #1 and #3 VSV's are in opposite locations on the diagram which I will attempt to attach and will post in a writeup in the files section when I get a minute.
That is to say I needed the forwardmost VSV (closest to the front bumper) which is the Air Injection one. In the diagram it is called #3. However, in the diagram for the FJ80 it is labeled #1 and is the rearmost one. I will try to get the actual part number off of each and post what they do in my writeup.
The old ones from my FJ62 had perminent wiring on number 1 & #3 VSV's, the middle one #2 just unplugged. I tried to dig out the silicone to see if there was a plug underneath but the wires were clamped onto the posts so I diked them off.
I used blue butt wire connectors on the diked off ends and had to trim off the flared end of the butt on the side that goes into the VSV. They fit snug and I believe will stay. After I am sure I will probably fill the area with di-electric grease and seal it off.
Results. If you look back at the symptoms I was seeing, sluggish or flat acceleration through about 23k rmp then turbo kick in like jump on up. Also, my idle was about 950 rpm at idle which is a bit high. I was getting dismal mpg as well. Jon Held said this sounded like what his rig was doing when his EGR system laid down. I had just replaced my EGR and vacuum modulator so I figured it was something else. I had checked my timing and it was retarded. Perhaps because my CEL due to the fried O2 sensor wiring for the front one. After I replaced the engine wiring harness my truck was CEL free but the symptoms began.
I am thinking the ECU reached an equalibrium with the fried harness and the timinmg was set accordingly. Regardless, after I advanced the timing performance improved but the problem still existed, it just moved higher up the power band.
With the new VSV's I Warmed up the truck and test drove it. It idled at about 550rpm smoothly. It pulled consistently through the power band without the flat area I saw before. It still pulled harder above 2700rpm but I think that is just the nature of the beast. It is really noticeable in 3rd gear when I hold it and shift at 4k rmp. For those who do not know I have a H55F Toyota five speed transmission. From 3k to redline the thing really goes.
My hot rod is baaacck!
Dunbar
Oh, and death to bin Laden.
