High idle problem

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Ratpatator

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I have a small problem with the truck idling high after I touch the gas pedal whether I'm in any gear but most noticable in park or neutral because it revs to 2 grand for about 30 seconds then idles back down to normal.

I just put kooks long tube headers, y pipe, bbk intake, s&b cold air, new lower spark plugs, misimoto oversized rabiator and a 170 degree thermostat and tunes from 5 star.

The truck ran great for the first two days then after a 8 hour round trip the truck now wants to idle high when in park or neutral. I'm lost at this point.
 
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Ratpatator

Ratpatator

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Who did your tune?

5 star tuning.

I've been talking with one of there guys and sent him a few data logs so they can see what's going on. He said it looked like a throttle body issue so I switch back to the original tb and he sent me a new tune for that and it still runs the same. I've also tried several of the tunes and returned to stock and it doesn't fix anything so I don't think it's a tuning issue.

I've put a new maf on new front o2 sensors checked wiring and plug-ins checked hoses and for vacuum leaks can't find anything.

The last thing I did before I noticed something wrong was fuel up. So tried some Lucas additive this morning hasnt helped it yet.

I'm lost at this point....
 

B E N

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I did not have a great experience with my 5 star tune, lots of problems. I think it's been mentioned by ohters as well. I did my own tune with Hptuners and it works well. Some time I need to sit down and analyze what they changed that made it go all crappy
 
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Ratpatator

Ratpatator

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I did not have a great experience with my 5 star tune, lots of problems. I think it's been mentioned by ohters as well. I did my own tune with Hptuners and it works well. Some time I need to sit down and analyze what they changed that made it go all crappy
How much control do you have with the hptuner. I was messing with my sct and the only aftermarket option it had on the diy tune was a cold air.
 

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Hptuners gives you the option to adjust nearly every engine and transmission parameter, but it doesn't have any pre-loaded tunes. You have to write your own, or get someone to write one for you. You can also read the tune from 5 star and modify it. If you have the SCT already and don't want to get into hardcore tuning there are some tuning vendors people have had better luck with.

I have nothing against 5 star btw, I had their tunes in my ecoboost and they were excellent. I am not sure what the disconnect with the raptor is.
 

MTF

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HP Tuners never came up with a calibrated Tune for the Gen 1

Did you do all the mods and Tune at the same time?
If you did it's going to be hard to pin point what mod is giving the problem.

I would say it's not the Tune, at least that's NOT the first thing I would think is the problem.
You would have problems right out of the gate not two to three days later.

First thing I will ask, are you using the Pedal Commander?

Are you making sure you have upgraded to the latest firmware for the SCT device?
Are disconnecting the battery for 15 minutes after flashing the 5 Star Tune?

To me, it seems like you have unmetered air entering or exiting the emission system.

Did you connect the rear O2s, I know the Tune has them turned off but you still need them connected.
You can always do the rear O2 extenders so you can leave the rear O2s on.
 
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Ratpatator

Ratpatator

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Hptuners gives you the option to adjust nearly every engine and transmission parameter, but it doesn't have any pre-loaded tunes. You have to write your own, or get someone to write one for you. You can also read the tune from 5 star and modify it. If you have the SCT already and don't want to get into hardcore tuning there are some tuning vendors people have had better luck with.

I have nothing against 5 star btw, I had their tunes in my ecoboost and they were excellent. I am not sure what the disconnect with the raptor is.

I might look into that. I like the way the truck runs with the 5 star. The only problem that I have noticed with it is I don't like the way the trany shifts and the shift points. I have a good friend who's brother owns a high performance diesel shop but still does gasers depending on who and what they are and said he would put mine on a Dyno just havent had time to go in with work and everything else
 
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Ratpatator

Ratpatator

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HP Tuners never came up with a calibrated Tune for the Gen 1

Did you do all the mods and Tune at the same time?
If you did it's going to be hard to pin point what mod is giving the problem.

I would say it's not the Tune, at least that's NOT the first thing I would think is the problem.
You would have problems right out of the gate not two to three days later.

First thing I will ask, are you using the Pedal Commander?

Are you making sure you have upgraded to the latest firmware for the SCT device?
Are disconnecting the battery for 15 minutes after flashing the 5 Star Tune?

To me, it seems like you have unmetered air entering or exiting the emission system.

Did you connect the rear O2s, I know the Tune has them turned off but you still need them connected.
You can always do the rear O2 extenders so you can leave the rear O2s on.

I did do everything at once and I agree I don't think it's the tune because it ran good for the first two days. And because when I returned it to stock tune it still did the same thing.

No I'm not running a pedal commander never really liked the thought of it basically tricking the throttle control.

Everything is up dated now it wasn't at first, I didn't even think about that but that was one of the first things the 5 star guys said to do. Disconnected the the battery, and the rear o2 are hooked up and tuned for. It has the high flow catted y pipes.

A vacuum leak was the next culprit I looked and felt around all the hoses and even sprayed some throttle body cleaner around everything with it running at a last resort and there wasn't even a flinch. There is a hole in the front of the new throttle body that intersects with one in the back, looks like a defect from the factory but I plugged it and no change.

A friend said it almost sounded almost exactly like a bad fuel problem or bad fuel pump issue she had on her truck so I added some Lucas fuel additive. Now if the truck sits for several hours it will idle fine for a few minutes and then start acting up again. As soon as I get this tank drained down I'll make sure I get some good fuel in it with more additive. On a second note it ran fine untill some time after the last fill up and the tank was under a quarter full.

Man I miss carburators, distributors and timing lights...
 

MTF

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High-Flow or the Kooks Green Cats?
Stock cats are the best then Kooks Green Cats, both usually need rear O2 extenders.
the cheaper high-flow ones usually require the rear O2s to be turned off.

If you think you might have some bad fuel, I would get some Star-Tron Enzyme fuel treatment.
I use this twice a year, once in the spring and another treatment in the fall.

Finding a small vacuum leak is tough on these new engines.
That is why they do smoke tests now.

I'm like you, it was much easier back in the day, all you needed was some starter fluid an if she raced up you knew.

I don't believe I've ever heard any one that tried the BBK TB say it was good, all had problems.
You don't need it, there is nothing you're doing to increase the engine's capacity to suck in more air.
The stock TB can deliver more than enough air for increase air/fuel mix in the Tune.

Also I want to add that there have been times when switching Tunes or adding a revised Tune that glitches have happen.
Sometimes I has to reinstall twice to three times.
You need to pay attention to not have anything running, nothing on, open or close doors and windows, step on the brakes....ect...
I usually keep a battery tender on while doing a flash.
 
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