Not that I can find, Magnet. I spent a long time looking yesterday afternoon. I hope to get home before dark tomorrow, maybe get another look at it. I don't hear or feel any odd vacuum problems under the hood either. Truck is running fine, has a little more power than it did before the tune up. The idle seemed to settle down some this afternoon coming home, was barely goosing up just a bit and then coming back down. Maybe the PCM had to re-learn the old IAC after I had moved the pintle shaft like I did. I am hoping this new one will settle down too.

Jimmy

 

when in doubt, I'd say just leave it.

 

Hey Magnethead, or anyone else who might know...one thing I just thought of. Yesterday when I pulled the plug wires off a couple of my plugs, the wire boot was stuck on there pretty tight. I mean I had to yank on it hard to get it loose. I wonder if those 2 wires might have stretched the wires inside so now they don't make as good a connection? Can an engine still run OK or maybe run with a slight problem like a weird idle fluctuation with a couple plug wires that might be stretched like that?

Thanks

Jimmy

 

I don't think so. Just means there was no dielectric grease on the connections, so they oxidized/welded together. With the right angle boots, it would be hard to pull the wires loose from the connector.

 

Drove it to work today, idle was fine until it warmed up to operating temp. After that when I would stop at a red light the idle was back to surging form 700 to about 850 then back down again. It does it about every 10 seconds. I don't think the plug wires are bad, there is no spitting, hesitation or sputtering, no lack of power. Truck runs fine, just has this weird idle problem that showed up after I did the tune up.

I may try a new TPS. Thanks for your help.

Jimmy

 

I picked up a new TPS at Auto Zone on my way home from work tonight. I installed it a few minutes ago, it *appears* to have solved the problem. When I first put it on, I still had the fluctuation in RPM at idle. I let the truck run a few minutes, held the throttle at 1500 and 2000 RPM for a few seconds each, let it off, it idled back down to 700 and is now idling steady at 700 RPM sitting still in my driveway at normal operating temperature. I hope this is the final piece of the puzzle, that it really is fixed now. I have to drive it to work tomorrow to know for sure.

Thanks for your help Magnethead. I sure hope I am done with this problem for good now.

Jimmy

 

I think dodge designed these trucks around the "fun factor". Fun to drive, fun to work on, and fun to chase weird stupid issues that crop up randomly, most predominantly in the electronics systems.

 

Spoke too soon..idle is still pulsing up and down every 10 seconds or so, but is not as bad as it was before. I guess I need to keep looking for a loose or cracked hose or some other vacuum leak. That is the only thing I can think of that would cause this idle fluctuation...I will leave it alone until the weekend, try to see what I can find in the daylight on Saturday. I am pretty tired of it right now.

Jimmy

 

Maybe I spoke too soon again....

My truck ran beautifully coming home from work, I can definitely tell the new TPS made a ton of improvement. The throttle response is much more crisp and precise and the dead zone at 60 mph is long gone. I could not really test that in the morning commute traffic today but I was able to get on it coming home. My truck is a lot more responsive now.

Coming home when I stopped at a red light 4 or 5 miles from work the idle was normal, precisely at 700 RPM and steady. There was no fluctuation at all. Same thing at a couple more lights here in town and the same thing also happened in my driveway when I got home. Steady 700 RPM. The gas needle does not look like it is dropping as fast now either.

I am thinking/guessing the PCM needed more driving time to learn and calibrate the new TPS. I am calling it done and leaving well enough alone unless it starts the wonky idle again.

Thanks again for your help Magnethead.

Jimmy

 

Did you reset the PCM after changing these sensors? That may have just been the problem after changing the tps. But at this point it's almost learnt the new sensors and re-adjusted itself