Significant Loss of Power - Help Diagnose

[Wicked_Sludge]

That appears to be the plug but I'm guessing that's on a V6.

'93 3.0

 

[Mutant Pony]

The symptoms to me sound like low fuel pressure. Has the pressure been tested?

 

[wmcclay]

Is this a calif. truck? they are a little different than the other 49

 

[unclewolfie]

Ah, thanks for the photos; that, along with some additional reading, I found it. Quite obvious, as it does stick out of the wiring harness right next to the ICM. Although I don't have my timing (in between moves and it is packed away at a buddy's house; I know, that was dumb) I did remove the SPOUT connector, started the engine and then when I plugged it back in, the RPMs went back up, like they should. So, I believe I have timing advance; although, I was really thinking that was the problem.

I did run tests for codes again, since I have done a few things. KOEO test now revealed a Power Steering Pressure Switch open connection or circuit failure (code 519). I'm assuming this is unrelated, although interesting.

In running the KOER test, it came up with no problems found.

I'm taking the truck to a recommended mechanic tomorrow (Thursday), as I'm about out of things that I am willing/able to do, unless someone comes up with a new suggestion.

 

[unclewolfie]

Yay, Hurray, Yippie! FIXED. Not sure it ended up being one specific thing, but the things that were replaced that may have contributed to this problem were; new fuel filter, one new coil and new plugs and wires. The last thing done was the plugs and wires and that really made the final difference. It was believed that one of the plug wires had gone bad. So, there ya go.