I bought a 1990 4runner 3VZE SR5 5sp. that had dropped an intake valve, so i got it for cheap. Good looking truck . Had a few things otherwise to fix but the guy/guys who owned it before were some top quality hacks. I beleive in you fix it right so that you fix it once. I have learned that though years of being an engine machinist. But on to my problem. Someone ripped the battery out of this thing once and riped some of the grounds and the main power to the computer or fuse box I think. Someone spliced in a smaller wire to the white power wire and that broke yesterday so yay!! I got to fix it. So i look at the other side of the battery and notice from the battery post there is one ground running to the firewall, one to the block and there is only 2 inches coming out of the battery post from an old wire and I am wondering if that goes to the computer or fuse box or something. I keep getting code 52(knock sensor) and code 43(starter signal) so i replaced the knock sensor and the pigtail (both brand new), and still get code 52. When i measured the voltage coming off both connectors that go to the knock sensor pigtail i got 756 volts on both. So I don't know if that's good or bad. Anybody have an Idea of what the voltage should be at? Second of all is there anything else further up besides the knock sensor and pigtail that could cause the problem?
Before I start it for the first time after reseting the computer, when you jump the terminals to get the code, the light is already flashing malfunction. So needless to say I am getting tired of it. I was hoping maybe that negative ground that goes nowhere might hold the key.

Any assistance would be greatly appreciated.

Thanks guys

 

you should not get any voltage reading from the knock sensor, the knock sensor sends a voltage to the computor if the engine knocks. The knock sensors makeup creates a small voltage from the vibration which is measured with a ocilliscope. Probably will need to replace the knock sensor wire the the computor. It is a shielded wire . The wire coming from the battery post if it is a small one probably bolts to the fender well right next to the battery. The computor grounds bolt directly to the intake at the back and are brown.

 

That voltage reading should be point 756(.756) of a volt. Not 756 volts as in my first post. That is the volts I could measure from the harness (computer) side, on the terminals that run back to the computer.