fastcam91

ttt

Injuneer

I tried to make sense out of your data, but its totally unclear. I suspect this is why you aren't getting any responses.

Lets clarify what it appears you did - you put the red lead from the volt meter on the TPS end of the gray wire, and the black lead from the volt meter to pin B6 of the PCM, and "the volts shoot all the way up past 5V"? What was the exact reading?

Or were you reading acrosss pins B6 and B28?

Now you are at the TPS end of the harness, you are touching the red lead to the gray wire, and the black lead to the black wire, and the meter reads "about 4.5V". What was the exact reading? You should have 5V at this point, reading it with the harness connector unplugged.


Unclear what points you were measuring. If you have the connector unplugged from the PCM, why would you get any readings at all on the wires?

In the reference to the diagnostic post, appears you have now measured the voltage using a scanner. You indicate you got "yes" on step 1. That means you saw 0.2V or less on the scanner. What was the exact voltage?

Then you shorted the gray reference voltage wire and the blue signal wire together, and the scanner read more than 4V?

Is this correct?

With no wires shorted, what does the scanner read at WOT? When you move the throttle blades slowly open, does the voltage change smoothly?

fastcam91

For the first question I had the the connector plugged into the pcm. I also had the key turned but engine not on. I put my red lead on the gray wire from B6 and the blk lead on the black wire on B28. The volts jumped all the way up to where there wasnt an exact reading. I am using a meter with a needle not digital.

Second question I touched the red lead to the gray and the blk lead to the ground of the connector. The volts were at about 4.5v.

Third, I didnt use a scanner just he same meter I am using. I also didnt short a blue wire. I justknow that I got 2volts and no more. I tried moving the throttle about everytime I checked voltage numerous ways and it never did increase volts at all.

Thanks for your patience I am just very stupid when it comes to electricity, since I have never worked with it ever.

Injuneer

Do not back-probe the PCM with a low impedance analog (needle) meter. You need a high impedance digital meter, or you can do damage.

You said you did the tests using the diagnostic logic chart. That chart is based on using a scanner that is pulling the voltage reading from the PCM. Step 2 required shorting the two wires (blue and gray) together. If you didn't do that, it isn't a valid test.

I think you need to take it to a shop, where they have the right equipment, and are comfortable with electrical issues.

fastcam91

how could it do damage to the pcm? Anyways I guess I will need to when I get back from deployment. Would my engine be fine if it sits for 6mo and doesnt get started, I dont want to do any damage to the engine the way it is misfiring and all.