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Discussion Starter #1
Hello, new to the forum. I hope through this post we can narrow down my problem and also help some other along the way that might be searching for a resolution.

The problem:
My truck will sometimes die at idle, lets say once out 30 trips around town. It will also feel like it is going to die and I have to pump the gas for a few seconds to get it back to normal, usually when just pulling away, say once every 15 trips around town. If I am in park and try to keep the idle at 1000RPM I will get hesitation and surging between 900 to 1100 RPM. Also, if I try to keep it at 1000RPM and turn the wheel to add some load, the idle will drop to @600RPM and surge [email protected] RPM when I let go of the wheel. IF I am in drive, other than the occasional die I can't reproduce the hesitation and surging if I keep it at 1000RPM. No codes (using the key on-off 3 times and also the trip button while turning the key on methods).

Here is what I have done to try to solve the problem (truck has 66,000 miles):
plugs
oxygen sensors
TPS
PCV
removed and cleans TB and IAC, neither of which struck me as being very dirty.

Most of the posts I read say "replace the TPS" or "replace the IAC" without a whole lot of explanation behind the suggestion. To help with the investigation I did the following tests:
TPS unhooked
IAC unhooked
TPS and IAC unhooked
TPS and IAC both hooked up

Results:
TPS unhooked and IAC hooked up
Idles a little rough at 600 RPM
If I keep it at 1000RPM it stays pretty steady. If I turn the wheel it will drop to about 900 RPM and surge to @1100 RPM when I let go of the wheel.

TPS unhooked and IAC unhooked
Idles rough at about 400RPM
harder to start
If I keep it at 1000RPM is stays pretty steady . If I turn the wheel it will drop to about 900 RPM and surge to @1100 RPM when I let go of the wheel.

I just realized the results of the above two are pretty much the same except for the initial idle.

TPS hooked up and IAC unhooked
much harder to start, need to give some gas to keep it going initially.
If I keep the idle at 1000RPM it hesitates and surges between 900RPM and 1100RPM. If I turn the wheel it will drop to @600RPM and when I let the wheel go it surges back to @1200RPM and then back to 1000RPM.

Both hooked up
Starts fine and idles smooth at 600RPM.
If I try to keep it at 1000RM it fluctuates between @900 to @1050 RPM. If I keep it at 1000RPM and turn the wheel it drops to @600RPM and then surges back to @1200 RPM before returning to 1000RPM.

I just realized the results of the above two are pretty much the same except for the initial idle.

So, I am not sure what to make of all that. Anyone have any thoughts? And, thanks in advance
 

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I have the same engine and can address the surging when you turn the wheel. That is the power steering pump wanting more power so the computer gives it a little more. As far as the truck wanting to die at idle, mine has done that on occasion, and I chalk it up to that's just what it does. Doesn't happen as often as yours, but it has happened.
I gotta ask, why are you trying to keep your idle at 1000rpm? Mine idles great between 5 & 6.
 

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Discussion Starter #3
I don't think I was real clear on keeping the idle at 1000. My normal idle is around 600. I don't experience any fluctuations if I just leave my foot off the gas. However, if I raise the idle slightly by keeping my foot steady on the gas, I experience the fluctuations. It seems that if I try and keep it around 1000 I see the most fluctuation. The higher I raise it about 1000 I see less an less fluctuation. If I get up to about 2000 the fluctuations almost go away. So, foot off the gas, pretty good idle. Try to keep it around 1000 the RPM fluctuate.
 

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Discussion Starter #4
Also, it may just be a progression of the issue but we have had a few really warm days over the last week and it seems like the issue is slightly worse.
 

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With the heat making it worse, that points to the AIT (Air intake temp.) sensor.
 

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Discussion Starter #6
Thank you for the response. I'll search around but do you know if there is a way to test it? Being a temp sensor I doubt it but the question is worth a shot. Maybe functionally testing it like unhooking it?
 

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Discussion Starter #7
And just to be sure, the AIT is the one plugged into the big black box (that's a technical term) on the top of the motor, right?
 

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And just to be sure, the AIT is the one plugged into the big black box (that's a technical term) on the top of the motor, right?
Don't wanna get too technical now, so we'll go with the big black box, yes. Pull it out and clean it up a bit. See if that helps any.
 

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Not off hand, I don't. Bumping it to the top so someone else may see it.
 

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Discussion Starter #12
Just to add... Running around town today it died once and felt like it was going to die 2 other times. All three happened when backing out and going from reverse to drive. As soon as I started to pull away in drive the hesitation/dieing happened.
 

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Discussion Starter #13
I also have the airbag light on. It is on most of the time but every now and then will go away for a few minutes. I didn't think this was relevant but I happen to come across some other information that indicated some components in the airbag system (the clock spring) might cause issues with a TPS.
 

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Discussion Starter #15
I tried a new IAC from autozone but I had a hard time keeping an idle. It would idle at @500 RPM and die every now an then. I put back in the original IAC and also put back in the original TPS since the new ones seemed to make the issue worse.
 

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Discussion Starter #16
Well, here's the story. One of the things I did a few months ago was to replace the O2 sensors. I used Bosch Premium. I couldn't remember if the stalling and wanting to stall happened before I replaced them or not. I put back in the original O2 sensors and the problem I had of wanting to die seems to have gone away. I post again if the problem comes back.

Also, and I have no idea why (any opinions would be appreciated), as soon as I put back the factory O2 sensors, by airbag light went out (has been on for a month or so solid). I think the airbag light originally came on some time after I replaced the sensors.

Thanks to those that took the time to respond to my posts. Hopefully this can help someone out.
 

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That's really weird about the airbag light. That's a real head scratcher...:4-dontknow:
 

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Discussion Starter #18
Airbag light has came on and went off a few times since. It appears to be an odd coincidence.
 

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Airbag light has came on and went off a few times since. It appears to be an odd coincidence.
I saw on youtube that there is a connection on the back of a seat (driver or passenger) and that connections gets loose sometimes.
I have airbag on on my truck but I had dealership to fix it for me. It was a faulty connection.
 

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Airbag light has came on and went off a few times since. It appears to be an odd coincidence.
This has happened with my truck since I bought it. I am so used to it now that I don't even hear the "ding" most of the time when it comes on.
 
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