[Durango_Traveler]

Well, the Fastman TB installation has been completed. All I can say: Wow! The truck feels much peppier now. Works nicely with John's z-tube setup and the 9" ProFlow filter.

The only bummer: Now, whenever I get the truck past 2,500 rpm, it hunts for the correct idle speed. At idle, it'll fluctuate between 400 and 800 rpm. Interestingly, when I first start the truck, it'll idle perfectly @ 500 rpm. As soon as I drive around and pass the magic 2,500 mark, it'll start hunting when I come to a stop.

I spent three hours today at the dealership, working on a few other things (replacement of rear bumper support being one) and had Chris and Larry (their senior mechanics) look into the issue. No vacuum leaks were found, PCM wouldn't show any fault reading. I'll head back there on Monday and we'll hook up the truck to a bunch of computers to see what it's going on between the PCM and the sensors whenever the truck hunts for the correct idle speed.

My initial suspicion is that the IAC is on its way south. It was a pain in the rear end to get it out and off the stock TB and I DID not clean it before putting it into the Fastman TB. If cleaning doesn't do the trick, a new IAC it's. I'll keep you all posted how this plays out.

Best,
Nico

 

[EyeSpy]

It may also take a little time for the 'puter to learn about the new TB? I had much the same issue when cleaned my TB for the first time? eratic idle, would stay opened up to 1500 rpm, but after driving it around for a little bit, the computer learned how a clean TB should be and all smoothed out? Give it 50 miles or so and see what hapens? if all the same, new TPS/IAC might be in order?

 

[jimbo]

You might also check the Throttle Position Sensor. A dirty/worn TPS will cause fluctuations at idle. They're relatively cheap, around $26, and available through AutoZone, Wells TPS333. The TPS333 is the exact same sensor as DC uses, it even has the same numbers laser marked on it.

A dirty/worn TPS won't usually throw a MIL code.

 

[FSTDANGO3]

Another Thought

There was a situation a while back with Z tube owners having IDLING or Surging Problems Sorry I don't remember the fix or if it justr went away after PCM recognized the changes.
If that isn't it I'd go with TPS as well
Steve
VP
DOC

 

[skitzo.d]

Mine was doing that soon after I bought it with 27000 miles on it. I also installed a TB and replaced the IAC and TPS when I did the swap. no problems after that. I too had it at the stealer and they found nothing so they gave me the death flash. that was the last time they touched my truck? :wall:

 

[Thunderchild]

Well I just orederd mine?

I had one on my 2K and when I traded it in I left it on sseing as how I gave my core back to the Fastman. Now I have ordered one for my 2K3. I look forward to this install. Easy and straight forward. GOOD MOD!!!