replaced.

 

With the the truck in neutral (not moving), how does the throttle react when you:

1. accelerate from idle to WOT smoothly
2. hold throttle at various RPM's
3. let off throttle completely from high RPM's

Does it hesitate or sputter at all under any of the above situations? Does it return to idle smoothly when you let off the accelerator?

 

sputters around 2000 rpm. I assume this is the "dead" spot in the throttle on the highway. Everything else normal.

 

Does it still seem to be running rich? Any power issues?

 

no power issues and no rich running conditions.

 

yeah id replace that thingy there that way it will drive like no other ya know?

 

Hate to take you in circles, but it sounds like a "non-linear" spot in the resistive tract on the TPS. I would be tempted to mark the on the throttle body that corresponds to position where you are at 2000 RPM's and measure the resistance as you slowly sweep past that point. Look for resistive spikes or drop-outs around that point. Your thoughts Matthew?

 

You may be right. What makes it difficult is that this problem is not always present... Maybe 1/2 the time. I will try to check the calibration this weekend to see if I get the linear resistance as I should.

 

Linear resistance test? Sounds like the throttle angle (VTA) sweep test I've mentioned.???

If so, yeah...that's a good idea. I'd hate to suspect the new TPS, so I'd also check at the ECU on the related terminals to see if the signals are getting there proper like. Just hook the ohm meter to the back of the terminals at the ECU....with the connector unplugged, of course. Run the same test as you would at the TPS. Might need some other hands and eyes to do this, unless you're meter stretches pretty far to where you can see it as you're working.

If the TPS passes, but the wiring harness test fails then it's the connector at the sensor or the wiring itself. You'd then need to inspect you're connector and/or test the wiring for continuity/resistance.

If the wiring test passes, then check the ECU itself. Cross that bridge if you come to it

 

Well for whatever reason, I haven't experienced any issues for the past few days. Problems never go away, they just hide, so I'll wait until it starts happening again before troubleshooting. I also suspect TPS.

I went and adjusted the valves after I got home from driving the truck on Friday. (HOT!) No noise now. Sounds great!! Anyway, filled up for the first time since getting everything lined out and was able to granny out a respectable 22+ mpg. Granted this was 75% highway driving and I never held it over 65mph for very long at all, but with gas prices like these, I'm good with it!

When I get my camera back home (left at office) i'll take another video of how nice and quiet she runs!

 

The problem may have cleared up, Kyle. At the risk of being redundant, ECU's to have to adapt/reset themselves to sensor input and operation patterns.

Do you think adjusting the valves has anything to do with not experiencing the stuttering?

 

don't think the adjusted valves did it because today is the first day this week I drove it to work with the valves adjusted.