You need to back probe the connection. By "back probe", I mean to use a long, thin probe with a nicely rounded tip (so as not to cut/tear the weather pack seal) to push past the seal in the connector while still connected to the TPS sensor. As stated in many other threads discussing TPS sensors, there will be a ground, +5V reference, and the sensor return to the ECU. You can determine which is the sensor return through a process of elimination since this terminal should be ~0.5V at closed throttle and ~4.5V at full open throttle.

 

I believe it is working best I can tell. I am getting about .6v closed and 4.7v open.

 

I talked with a mechanic today and without him really looking at it he seems to think it is the fuel filter. After sitting up for years he says it will create gum and trash in the fuel tank and lines and it will clog the filter quickly. Guess I will try replacing it and see what happens.

 

sounds like an EGR problem if the TPS sensor doesn't work

 

Atvwarrior and my mechanic friend called it. I never would have suspected the fuel filter since it was only 2 months old. It never dawned on me the trash/rust and gum that has been building up in the fuel lines and tank for last several years of sitting.

I pulled the filter and rusty fuel oozed out of the input side of the filter. I removed it completely and flushed it backwards with fuel. I couldn't believe all the trash coming back out. Though it should have been obvious after knowing how rusted the sending unit and fuel pump were.

I'm not going to change the filter just yet. I figured I would let run another tank full or two before replacing it to make sure I get the majority of the trash out.

 

I suspect I may have a clogged fuel filter. 91 Blazer 4.3 4wd is backfireing and stalling out. If I turn it off for a min. it starts and runs fine for a couple min....then starts the bog down, backfire, stall thing again.

Question: can I clean a fuel filter out with water and let it dry in the sun? Do I have to flush from a specific side of the filter. Thanks for any help.