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2018 Jeep Trackhawk
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Discussion Starter · #1 ·
From day one, my TH has not felt much more powerful than my last SRT8 with the 6.4l. it now has 2500 miles on it and have been testing launch mode at all RPM ranges and the best time is 4.2 seconds. I'm running the Pirrelli stock 4 season tires at 30psi. Noticed today that with launch mode enabled it is showing zero boost psi, and after launch it showed a maximum of 5 psi. Any ideas what might be going on here?
 

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2018 Jeep Trackhawk
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From day one, my TH has not felt much more powerful than my last SRT8 with the 6.4l. it now has 2500 miles on it and have been testing launch mode at all RPM ranges and the best time is 4.2 seconds. I'm running the Pirrelli stock 4 season tires at 30psi. Noticed today that with launch mode enabled it is showing zero boost psi, and after launch it showed a maximum of 5 psi. Any ideas what might be going on here?
Maybe the belt on the pulley is slipping?
 

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From day one, my TH has not felt much more powerful than my last SRT8 with the 6.4l. it now has 2500 miles on it and have been testing launch mode at all RPM ranges and the best time is 4.2 seconds. I'm running the Pirrelli stock 4 season tires at 30psi. Noticed today that with launch mode enabled it is showing zero boost psi, and after launch it showed a maximum of 5 psi. Any ideas what might be going on here?


My max boost under load is 11psi. What are your max HP and torque numbers under performance pages?
 

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Thought this was a duplicate post from other forum until I noticed the dates.

He used the Uconnect to datalog hp/torque and boost. It peaked at ~400 and ~ 5psi boost. Jeep rep had to come to diagnose and I think the issue was programming and key fob related? He is running low 3's now...
 

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Discussion Starter · #5 ·
I'll be trying the other key fob tonight, I haven't analyzed the HP and other screens yet, just times and boost for starters. I had a 2014 SRT8 that was faster than this TH, so I know there are problems. Hoping it is the same faulty key issue!
 

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Key fob was the problem, switched to my other one today and I'm hitting 11psi boost and 3.4 sec 0-60 consistently! Thanks for all the help!
Awesome, glad you got it working!

Must have been a run of incorrect internals put into RED fobs... I have now seen 3 people with this problem.

Interesting though that it now appears that we have the same feature as hellcats (reduced power fob option) we just get two red fobs instead of one of each at delivery...

Could be useful for anyone who may have a younger driver in the household...
 

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Discussion Starter · #8 ·
exactly, I'm going to try and get it replaced but hang onto the old one in case I ever decide to loan her out.
 

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What is the easiest way to tell if you have a key issue? I just got mine so too new for launch mode. Fells a little quicker than my SRT, just want to be sure. If I get on the throttle hard while cruising how much boost should I be getting, if that's the easiest way to tell. Thanks!
 

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What is the easiest way to tell if you have a key issue? I just got mine so too new for launch mode. Fells a little quicker than my SRT, just want to be sure. If I get on the throttle hard while cruising how much boost should I be getting, if that's the easiest way to tell. Thanks!


Max boost 11 psi
 

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2018 Jeep Trackhawk
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What is the easiest way to tell if you have a key issue? I just got mine so too new for launch mode. Fells a little quicker than my SRT, just want to be sure. If I get on the throttle hard while cruising how much boost should I be getting, if that's the easiest way to tell. Thanks!

I feel the same way. Yeah, it's fast no doubt, but i also drive a tuned Audi RS7 and 17 Viper, so not quite sure what to expect.
 

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2018 Jeep GC TH
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I'm having the same problem with both keys. Under hard acceleration, I have little or no boost.
 

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For us old folk who don't know anything about boost, can someone walk us through what to do to know definitively whether we have a key/boost issue?
 

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For us old folk who don't know anything about boost, can someone walk us through what to do to know definitively whether we have a key/boost issue?
Good question. That would help a lot.
Open your SRT pages and watch the horsepower and boost readings under repeated launches and full throttle pulls from 40 or so MPH. They should not be peaking at 500HP or less or 5psi or less. Should be hitting close to 700HP and 11psi.

**goes without saying, but ensure you choose an open and safe area to do this ;)
 

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2018 Jeep GC TH
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I've done as you suggested. At full throttle the torque and HP are peaking at around 500 and boost is 1-3 in Hg (2-6 psi).
 

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I've done as you suggested. At full throttle the torque and HP are peaking at around 500 and boost is 1-3 in Hg (2-6 psi).
Did you try both Key Fobs? Some are having the issue with both but others only had an issue with one fob, the second gave them full power...

Also, here is some great info from another poster on another forum (who appears to have the issue with both fobs)...

lopp said:
Just an update in case anyone else struggles with this. Check your own Trackhawk to be sure you're getting full performance.
When you turn on the ignition, hit the drive modes button and look at the color of the engine on the performance page center console. It should be red. If the engine is yellow, that means it is operating in "black key" mode, even though the Trackhawk doesn't come with a black key. It is limited to 500hp.
The dealer has to order two new keys, delete the key fob programming and reprogram those two new keys.
 

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2018 Jeep GC TH
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Thank you for helping with this. Yes both keys and the engine is yellow in drive mode app. I would have never figured this out without your help.
 

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Thank you for helping with this. Yes both keys and the engine is yellow in drive mode app. I would have never figured this out without your help.
Happy to help. I fear my TrackHawk has the same problem. Unfortunately I havent been able to drive it for a month (Various reasons, nothing to do with FCA) to find out so I have been closely tracking this one and learning what I would be testing for when I get it back. (Hopefully this Saturday.)
 

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Checked my TH today... Did some pulls in auto and sport. I saw a boost of 11 and HP in the low to mid 600s. Highest of 695 hp, but widely variable. Also, hitting the drive mode button shows a red engine and everything else yellow. If I switch to sport and track, everything else goes to orange or red, but the engine is always red. So I'm good (with that one key)?
 
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