check ur ohm readings on ur TPS sensor mine does the same ลลลล and its the TPS newone fixed the problem.

 

i find it very hard to believe a 1/2 full tank (maybe it it were 1/2 empty) would affect the distibutor. bushing 'contacts' for what? there are no points involved, only spinning bits (rotor and p/u) that if they were making contact u'd know immediately, check for shaft movement or unusual wear under the cap.

 

Any new updates?

 

whats a tps?

 

Throttle Position Sensor. It's a variable resistor (potentiometer) that is tied to the throttle body. By reading the output (read: resistance) of the pot the computer is able to determine what throttle position the throttle plate is at. This information is used to compare against tables that are programed into the ECU that dictate timing and fuel adjustments. When the ECU recieves the wrong information is usually makes adjustments that are less than desirable.

 

have you checked the main distributor wire??? or the plugs and wires or the Cap and rotor... bet it's electrical... check your main Plug Wire (center wire from the coil) if it's got a short or a break in it that can happen. But TPS sounds very resonable too.

 

Unfortunately no updates yet... Just surviving. As long as I keep the tank over half full the truck runs fine. Still on the case though and I hope to get to the bottom of this soon!!!!

 

TS86 anythihg yet?

So I have a similar problem, BUT much more random. So I noted that if I kept from tightening the gas cap all the way say go to full lock then back off a 1/4 turn I had no stumbles. I wonder if there was too much vacuum in the system so much so that the pump could not push fuel anymore. I know it makes no sense, but I went about 5 tanks of gas with no stumble. I then tightened to full lock and lo and behold a stumble.

I am leaning towards the distributor, but I checked and was pretty close to spec.

JJ